analysis(tdcs): GLM hypothesis tests + methods for the reaching study

Poisson GEE / binomial rate / learning-rate models, subject random-intercept
sensitivity, unknown-group classification and merge scenarios, plus METHODS.md
and learning-curve plots. Data reconstructed from the experiment DB and
verified against the exported matrix.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

analysis/METHODS.md

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+# tDCS reaching study — GLM methods
+
+This document explains the statistics in `tdcs_glm.py`: the models, the exact
+formulas, how each subject's progress is accounted for, and the caveats.
+
+## The question
+
+Two **known** conditions anchor the performance scale and differ from each other:
+
+- **H2 (anchor check):** `Electrode-Box-B2` performs **better** than `Electrode-Box-A2`.
+
+Two **unknown** conditions are then **classified** against those anchors — for
+each of `Electrode-Box-A` and `Right-Electrode`, is it **A2-like** or **B2-like**?
+We do *not* assume either belongs to B2; each unknown is compared to *both*
+anchors, and the anchor it cannot be distinguished from is its likely class.
+
+There is also a **merged-assumption** mode (`--merge`): assume the two unknowns
+resolve as `Right-Electrode == Box-B2` and `Electrode-Box-A == Box-A2`, fold them
+into the anchors, and re-estimate everything with 4 subjects per group.
+
+## Data and outcome
+
+- **Outcome:** `success` = successful reaches in a session
+  (`analysis_summary.counts.Success`), a non-negative **count**.
+- **Attempts:** `total` = reach attempts in the session (`analysis_summary.total`);
+  used as the denominator for the rate model. `success_rate == success / total`.
+- **Time:** `day` = the "# Days Reach" field (training day, 0..26). Analyses use
+  days ≥ 0 (pre-training negative days and zero-attempt sessions are excluded;
+  zero-attempt sessions are undefined for the rate model).
+- **Groups (subjects):** Naive (4), Box-A2 (3), Box-B2 (3), Box-A (1),
+  Right-Electrode (1). Under `--merge`: Box-A2 (4), Box-B2 (4), Naive (4).
+
+**Provenance:** `tdcs_reach_data.csv` was reconstructed from the experiment
+database and verified cell-by-cell against the exported matrix (71/71
+unambiguous cells on days 0–5 matched exactly).
+
+## The three models
+
+All models use `Electrode-Box-B2` as the **reference** group, so each group term
+is that group's contrast *versus Box-B2*. `day_c` is the centered training day and
+`day_c2 = day_c²` captures the rise-then-plateau of the learning curve.
+
+### (A) Level — count (primary)
+
+Poisson GEE on the success counts, clustered by subject:
+
+```
+success ~ C(group, Treatment('Electrode-Box-B2')) + day_c + day_c2
+family        = Poisson (log link)
+groups        = subject           # repeated-measures cluster
+cov_struct    = Exchangeable      # working within-subject correlation
+SE            = robust (sandwich)
+```
+
+`exp(coef)` for a group term is an **incidence-rate ratio (IRR)**: expected
+successes relative to Box-B2.
+
+### (B) Level — rate
+
+Binomial GLM on successes-out-of-attempts, with cluster-robust SEs by subject:
+
+```
+cbind(success, total - success) ~ C(group, Treatment('Electrode-Box-B2')) + day_c + day_c2
+family   = Binomial (logit link)
+cov_type = cluster (groups = subject)
+```
+
+`exp(coef)` is an **odds ratio** for a successful reach relative to Box-B2. This
+controls for differing numbers of attempts, so it answers "who is more accurate
+per attempt?" rather than "who attempts more?"
+
+### (C) Learning rate
+
+Poisson GEE with a **group × day** interaction, to ask whether groups improve at
+different *rates* (not just different levels):
+
+```
+success ~ C(group, Treatment('Electrode-Box-B2')) * day_c + day_c2
+```
+
+Each `group[T.X]:day_c` term is the difference in log-slope versus Box-B2; a joint
+Wald test asks whether *any* group's slope differs. Large p ⇒ parallel learning.
+
+### Anchors-only model
+
+The A2-vs-B2 comparison, refit on **just the two anchor groups** so nothing else
+influences the shared day terms or the dispersion/correlation nuisance:
+
+```
+# subset to {Box-A2, Box-B2}
+success ~ C(group, Treatment('Electrode-Box-B2')) + day_c + day_c2     # count
+cbind(success, total-success) ~ C(group, ...) + day_c + day_c2         # rate
+```
+
+With B2 as reference the single group term is the A2-vs-B2 effect; H2 is a
+one-sided test that this coefficient is below zero.
+
+## How each subject's progress is accounted for
+
+Two distinct pieces:
+
+1. **Progress over training** — the `day_c + day_c2` fixed terms model the average
+   learning curve, so groups are compared at comparable points in training rather
+   than being confounded by *when* each was measured.
+
+2. **Repeated measures / individual baselines** — each subject contributes many
+   correlated sessions and has its own baseline. Handled two ways:
+
+   - **Primary (GEE):** subject is the cluster; an exchangeable working
+     correlation plus robust (sandwich) SEs give *population-average* group
+     effects whose inference is valid under within-subject correlation and
+     Poisson overdispersion.
+
+   - **Sensitivity (mixed model):** a Poisson model with a **per-subject random
+     intercept** (`(1 | subject)`) so each animal gets its own baseline level;
+     the group effects are estimated after allowing for that individual variation.
+     statsmodels has no frequentist Poisson GLMM, so this is the **MAP/Laplace**
+     fit (`fit_vb` diverges on these large counts). Its p-values are approximate —
+     read it as a direction/magnitude check that should agree with GEE.
+
+## Classification logic (unknowns)
+
+For each unknown group, `diff_contrast` builds a linear contrast of that group
+against **each anchor** (both coded vs the B2 reference) and tests it:
+
+- indistinguishable from B2 **and** different from A2 → **B2-like**
+- indistinguishable from A2 **and** different from B2 → **A2-like**
+- indistinguishable from both → **ambiguous** (report the numerically nearer one)
+- different from both → **unlike both**
+
+## Caveats
+
+- **Tiny groups.** Box-A2/B2 have 3 subjects, Naive 4, and each unknown has
+  **n = 1 subject**. Classifying a one-subject condition is weak: "matches
+  anchor X" means "not statistically distinguishable from X," **not** proof of
+  equivalence.
+- **Single-cluster fragility.** Cluster-robust/GEE inference with one cluster in a
+  group can produce artificially small SEs — most visibly the learning-rate
+  interaction for the n=1 groups; do not read those p-values literally.
+- **Mixed-model confounding.** With a per-subject random intercept, a group made
+  of one subject is partly confounded with that subject's random intercept, so its
+  fixed effect is shrunk.
+- **Rate vs count.** "Success" alone is a count; the rate model (success/attempts)
+  is the fairer accuracy comparison when attempt counts differ.
+
+## Files and usage
+
+- `tdcs_glm.py` — the analysis (run it directly).
+- `tdcs_reach_data.csv` — the verified long-format data (`subject, group, day, success, total`).
+- `tdcs_learning_curves*.png` — per-group learning curves (count and rate panels).
+
+```
+python3 analysis/tdcs_glm.py               # all training days, 5 groups
+python3 analysis/tdcs_glm.py --max-day 10  # restrict to days 0–10
+python3 analysis/tdcs_glm.py --merge       # assume Right==B2 and Box-A==A2 (3 groups)
+```
+
+Requires: pandas, numpy, scipy, statsmodels, matplotlib.

analysis/tdcs_glm.py

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+#!/usr/bin/env python3
+"""
+tDCS reaching study — GLM hypothesis tests.
+
+QUESTION
+    Two KNOWN conditions anchor the scale and differ from each other:
+        H2 (anchor check): Electrode-Box-B2 performs BETTER than Electrode-Box-A2.
+    Two UNKNOWN conditions then get CLASSIFIED against those anchors:
+        For "Electrode-Box-A" and for "Right-Electrode", is each one
+        A2-like or B2-like? (We do not assume either belongs to B2.)
+    Each unknown is compared to BOTH anchors; a group it cannot be
+    distinguished from is its likely class.
+
+Each comparison is examined through THREE complementary GLMs:
+
+    (A) LEVEL / count      Poisson GEE on `success` (successful reaches per
+                           session), adjusting for training day. Answers
+                           "who makes more successful reaches overall?"
+
+    (B) LEVEL / rate       Binomial GLM on success / attempts
+                           (`success` out of `total`), cluster-robust.
+                           Controls for differing numbers of attempts —
+                           "who is more accurate per attempt?"
+
+    (C) LEARNING RATE      Poisson GEE with a group x day interaction.
+                           Answers "do the groups improve at different
+                           RATES?" (slope of the learning curve).
+
+All models adjust for time with day (and day^2 for the plateau) and account
+for repeated measures on each subject via GEE (subject = cluster,
+exchangeable correlation, robust SE) or cluster-robust standard errors.
+Group is coded with Electrode-Box-B2 as the REFERENCE, so H1 and H2 read
+directly off the group terms:
+    Right-Electrode term  -> H1 (expect ~0 / non-significant)
+    Electrode-Box-A2 term -> H2 (expect < 0: B2 above A2)
+exp(coef) is an incidence-rate ratio (count model) or odds ratio (rate
+model) relative to Box-B2.
+
+CAVEATS
+    * Tiny groups: Box-A2 n=3, Box-B2 n=3, Naive n=4, and each UNKNOWN
+      (Electrode-Box-A, Right-Electrode) has only n=1 SUBJECT. Classifying a
+      1-subject condition is weak: "matches anchor X" means "not statistically
+      distinguishable from X", NOT proof of equivalence, and cluster-robust
+      inference with a single cluster in a group is fragile (can show
+      artificially small SEs, especially in the learning-rate interaction).
+
+DATA PROVENANCE
+    analysis/tdcs_reach_data.csv was reconstructed from the experiment
+    database (experiment "tDCS", outcome = analysis_summary.counts.Success,
+    attempts = analysis_summary.total, x-axis = the "# Days Reach" field) and
+    verified cell-by-cell against the exported matrix (71/71 unambiguous
+    cells on days 0-5 matched exactly).
+
+USAGE
+    python3 analysis/tdcs_glm.py
+    Requires: pandas, numpy, scipy, statsmodels, matplotlib.
+    Writes: analysis/tdcs_learning_curves.png
+"""
+import os
+import argparse
+import numpy as np
+import pandas as pd
+import patsy
+import statsmodels.api as sm
+import statsmodels.formula.api as smf
+from scipy import stats
+import matplotlib
+matplotlib.use("Agg")
+import matplotlib.pyplot as plt
+
+REF = "Electrode-Box-B2"
+# Two KNOWN anchor conditions that differ (Box-B2 > Box-A2, see H2).
+ANCHOR_LOW = "Electrode-Box-A2"
+ANCHOR_HIGH = "Electrode-Box-B2"
+# Two UNKNOWN conditions to classify: is each one A2-like or B2-like?
+CANON_UNKNOWNS = ["Electrode-Box-A", "Right-Electrode"]
+ALL_GROUPS = ["Naive", ANCHOR_LOW, ANCHOR_HIGH] + CANON_UNKNOWNS
+# The active group config is set at runtime (after any --merge/--assign remap).
+UNKNOWNS = list(CANON_UNKNOWNS)
+MAIN = list(ALL_GROUPS)
+OTHERS = [g for g in MAIN if g != REF]
+# --merge preset: assume each unknown resolves into an anchor.
+MERGE_MAP = {"Electrode-Box-A": ANCHOR_LOW, "Right-Electrode": ANCHOR_HIGH}
+HERE = os.path.dirname(os.path.abspath(__file__))
+DATA = os.path.join(HERE, "tdcs_reach_data.csv")
+PLOT = os.path.join(HERE, "tdcs_learning_curves.png")
+RHS = f"C(group, Treatment('{REF}')) + day_c + day_c2"
+
+
+def gterm(name):
+    """statsmodels/patsy column name for a group level (vs the reference)."""
+    return f"C(group, Treatment('{REF}'))[T.{name}]"
+
+
+def xterm(name):
+    """Interaction column name (group level x day slope)."""
+    return f"C(group, Treatment('{REF}'))[T.{name}]:day_c"
+
+
+def load(max_day=None, mapping=None):
+    df = pd.read_csv(DATA)
+    if mapping:                                      # remap unknown -> target group
+        df["group"] = df["group"].map(lambda g: mapping.get(g, g))
+    df = df[df["group"].isin(ALL_GROUPS)].copy()    # keep canonical groups
+    df = df[df["day"] >= 0].copy()                   # training days only (day 0..)
+    if max_day is not None:
+        df = df[df["day"] <= max_day].copy()         # restrict the analysis window
+    df["day_c"] = df["day"] - df["day"].mean()       # center day
+    df["day_c2"] = df["day_c"] ** 2
+    present = [g for g in ALL_GROUPS if g != REF and g in set(df["group"])]
+    df["group"] = pd.Categorical(df["group"], categories=[REF] + present)
+    return df
+
+
+def contrast(res, tname):
+    """coef, robust SE, p, effect=exp(coef) and its 95% CI for one term."""
+    ci = res.conf_int()
+    lo, hi = ci.loc[tname]
+    return dict(coef=res.params[tname], se=res.bse[tname], p=res.pvalues[tname],
+                eff=np.exp(res.params[tname]), lo=np.exp(lo), hi=np.exp(hi))
+
+
+def one_sided_p_below(c):
+    """One-sided p for H: coef < 0 (i.e. Box-B2 above the compared group)."""
+    return stats.norm.cdf(c["coef"] / c["se"])
+
+
+def diff_contrast(res, a, b):
+    """Compare group `a` vs group `b` (both coded relative to REF) via a linear
+    contrast. Returns coef, robust SE, p, effect=exp(coef)=ratio a/b, and CI.
+    Works for any pair, including b == REF (then it is just the `a` term)."""
+    names = list(res.params.index)
+    v = np.zeros(len(names))
+    if a != REF:
+        v[names.index(gterm(a))] += 1.0
+    if b != REF:
+        v[names.index(gterm(b))] -= 1.0
+    tt = res.t_test(v)
+    coef = float(np.ravel(tt.effect)[0])
+    se = float(np.ravel(tt.sd)[0])
+    p = float(np.ravel(tt.pvalue)[0])
+    lo, hi = np.ravel(tt.conf_int())[:2]
+    return dict(coef=coef, se=se, p=p, eff=np.exp(coef),
+                lo=np.exp(lo), hi=np.exp(hi))
+
+
+# ----------------------------------------------------------------------------- models
+def fit_count_level(df):
+    """(A) Poisson GEE on success counts; group main effects vs Box-B2."""
+    return smf.gee(f"success ~ {RHS}", groups="subject", data=df,
+                   family=sm.families.Poisson(),
+                   cov_struct=sm.cov_struct.Exchangeable()).fit()
+
+
+def fit_rate_level(df):
+    """(B) Binomial GLM on success/attempts with cluster-robust SE.
+    Zero-attempt sessions (total==0) carry no rate information and are dropped."""
+    d = df[df["total"] > 0].copy()
+    dropped = len(df) - len(d)
+    if dropped:
+        print(f"[rate model] dropped {dropped} zero-attempt session(s) (undefined rate)")
+    X = patsy.dmatrix(RHS, d, return_type="dataframe")
+    endog = np.column_stack([d["success"].values,
+                             (d["total"] - d["success"]).values])
+    return sm.GLM(endog, X, family=sm.families.Binomial()).fit(
+        cov_type="cluster", cov_kwds={"groups": d["subject"].values})
+
+
+def fit_learning_rate(df):
+    """(C) Poisson GEE with group x day interaction (slope differences)."""
+    return smf.gee(
+        f"success ~ C(group, Treatment('{REF}')) * day_c + day_c2",
+        groups="subject", data=df, family=sm.families.Poisson(),
+        cov_struct=sm.cov_struct.Exchangeable()).fit()
+
+
+def fit_mixed_count(df):
+    """Subject random-intercept Poisson mixed model (MAP / Laplace).
+
+    Adds a per-subject random intercept so each subject has its own baseline
+    level; the group fixed effects are then estimated after allowing for that
+    individual variation. A subject-specific complement to the population-
+    average GEE. statsmodels has no frequentist Poisson GLMM, so this is the
+    posterior-mode (MAP) fit with a Laplace covariance for the fixed effects
+    (fit_vb failed to converge on these large counts; MAP is stable)."""
+    import warnings
+    from statsmodels.genmod.bayes_mixed_glm import PoissonBayesMixedGLM
+    vc = {"subject": "0 + C(subject)"}          # random intercept per subject
+    model = PoissonBayesMixedGLM.from_formula(f"success ~ {RHS}", vc, df)
+    with warnings.catch_warnings():
+        # MAP stops at |gradient|~5e-5 (effectively converged); silence the
+        # over-strict "did not converge" notice.
+        warnings.filterwarnings("ignore", message="Laplace fitting did not converge")
+        return model.fit_map()
+
+
+def mixed_contrast(res, tname):
+    """coef, SD, approx p and IRR + 95% interval from a BayesMixedGLM fit."""
+    names = list(res.model.exog_names)
+    i = names.index(tname)
+    mean, sd = float(res.fe_mean[i]), float(res.fe_sd[i])
+    p = 2.0 * stats.norm.sf(abs(mean / sd))
+    return dict(coef=mean, se=sd, p=p, eff=np.exp(mean),
+                lo=np.exp(mean - 1.96 * sd), hi=np.exp(mean + 1.96 * sd))
+
+
+# ----------------------------------------------------------------------------- reports
+def describe(df):
+    print("=" * 78)
+    print("DESCRIPTIVES")
+    print("=" * 78)
+    grp = df.groupby("group", observed=True)
+    tbl = pd.DataFrame({
+        "n_subj": grp["subject"].nunique(),
+        "n_sessions": grp.size(),
+        "mean_success": grp["success"].mean().round(1),
+        "mean_rate": (grp["success"].sum() / grp["total"].sum()).round(3),
+        "max_day": grp["day"].max(),
+    })
+    print(tbl.to_string())
+
+
+def report_level(title, res, effect_label):
+    print("\n" + "=" * 78)
+    print(title)
+    print("=" * 78)
+    print(f"Effect vs {REF} ({effect_label} relative to Box-B2):")
+    h = f"{'group':20s} {'effect':>7s} {'95% CI':>16s} {'coef':>8s} {'SE':>7s} {'p':>9s}"
+    print(h)
+    print("-" * len(h))
+    out = {}
+    for g in OTHERS:
+        c = contrast(res, gterm(g))
+        out[g] = c
+        ci = f"[{c['lo']:.2f}, {c['hi']:.2f}]"
+        print(f"{g:20s} {c['eff']:7.3f} {ci:>16s} {c['coef']:8.3f} {c['se']:7.3f} {c['p']:9.4f}")
+    return out
+
+
+def report_learning(res):
+    print("\n" + "=" * 78)
+    print("(C) LEARNING RATE — Poisson GEE, group x day interaction")
+    print("=" * 78)
+    base = res.params["day_c"]
+    print(f"Box-B2 learning slope: {np.exp(base):.3f}x successes per training day "
+          f"(baseline).")
+    print("Slope DIFFERENCE vs Box-B2 (exp(coef) = per-day multiplier on the rate ratio):")
+    h = f"{'group':20s} {'slopeΔ/day':>10s} {'coef':>8s} {'SE':>7s} {'p':>9s}"
+    print(h)
+    print("-" * len(h))
+    for g in OTHERS:
+        c = contrast(res, xterm(g))
+        print(f"{g:20s} {c['eff']:10.3f} {c['coef']:8.3f} {c['se']:7.3f} {c['p']:9.4f}")
+    # Joint Wald test: do ANY groups differ from Box-B2 in learning rate?
+    names = list(res.params.index)
+    idx = [names.index(xterm(g)) for g in OTHERS]
+    R = np.zeros((len(idx), len(names)))
+    for i, j in enumerate(idx):
+        R[i, j] = 1.0
+    jt = res.wald_test(R, scalar=True)
+    print(f"\nJoint test (all group x day interactions = 0): "
+          f"chi2={float(jt.statistic):.2f}, df={len(idx)}, p={float(jt.pvalue):.4f}")
+    print("  -> small p = groups improve at DIFFERENT rates; large p = parallel learning.")
+
+
+def report_anchor_only(df):
+    """A2-vs-B2 ONLY: refit on just the two anchors so nothing else influences
+    the shared day terms / dispersion. B2 is the reference, so the single group
+    term is the A2-vs-B2 comparison."""
+    print("\n" + "=" * 78)
+    print("ANCHORS ONLY — Box-A2 vs Box-B2 (two-group models)")
+    print("=" * 78)
+    d = df[df["group"].isin([ANCHOR_LOW, ANCHOR_HIGH])].copy()
+    d["day_c"] = d["day"] - d["day"].mean()
+    d["day_c2"] = d["day_c"] ** 2
+    d["group"] = pd.Categorical(d["group"], categories=[ANCHOR_HIGH, ANCHOR_LOW])
+    n_sub = d.groupby("group", observed=True)["subject"].nunique().to_dict()
+    print(f"subjects: Box-B2={n_sub.get(ANCHOR_HIGH)}, Box-A2={n_sub.get(ANCHOR_LOW)}"
+          f"   sessions: {len(d)}")
+    print(f"formula: success ~ C(group, Treatment('{REF}')) + day_c + day_c2")
+    for label, res in [("count/level (Poisson GEE)", fit_count_level(d)),
+                       ("rate/level  (Binomial cluster-robust)", fit_rate_level(d))]:
+        c = contrast(res, gterm(ANCHOR_LOW))
+        p1 = one_sided_p_below(c)
+        tag = "SUPPORTED" if (c["coef"] < 0 and p1 < 0.05) else "not supported"
+        print(f"  [{label}] A2/B2 = {c['eff']:.2f} [{c['lo']:.2f}, {c['hi']:.2f}]  "
+              f"=> B2 = {1.0 / c['eff']:.2f}x A2, one-sided p={p1:.4f}  -> H2 {tag}")
+
+
+def report_mixed(df):
+    """Subject random-intercept Poisson mixed model (sensitivity vs GEE)."""
+    print("\n" + "=" * 78)
+    print("SENSITIVITY — Poisson MIXED model, per-subject random intercept (MAP/Laplace)")
+    print("=" * 78)
+    try:
+        res = fit_mixed_count(df)
+    except Exception as exc:                       # VB can be finicky; degrade gracefully
+        print(f"  (mixed model skipped: {type(exc).__name__}: {exc})")
+        return
+    print("Group effect vs Box-B2 (IRR; each subject given its own baseline):")
+    h = f"{'group':20s} {'IRR':>7s} {'~95% CI':>16s} {'mean':>8s} {'SD':>7s} {'~p':>9s}"
+    print(h)
+    print("-" * len(h))
+    for g in OTHERS:
+        c = mixed_contrast(res, gterm(g))
+        ci = f"[{c['lo']:.2f}, {c['hi']:.2f}]"
+        print(f"{g:20s} {c['eff']:7.3f} {ci:>16s} {c['coef']:8.3f} {c['se']:7.3f} {c['p']:9.4f}")
+    print(f"  subject random-intercept SD = {float(np.exp(res.vcp_mean[0])):.3f} "
+          "(log scale); Laplace SEs, treat p-values as approximate.")
+    print("  Compare directions/magnitudes with the GEE table (they should agree).")
+    print("  Single-subject groups (Box-A, Right-Electrode) are partly confounded")
+    print("  with their own random intercept here, so their effects are shrunk.")
+
+
+def plot_curves(df, plot_path):
+    fig, ax = plt.subplots(1, 2, figsize=(12, 4.8))
+    for g in MAIN:
+        s = df[df["group"] == g]
+        d = s.groupby("day").apply(
+            lambda x: pd.Series({"succ": x["success"].mean(),
+                                 "rate": x["success"].sum() / x["total"].sum()}),
+            include_groups=False)
+        ax[0].plot(d.index, d["succ"], marker="o", ms=3, label=g)
+        ax[1].plot(d.index, d["rate"], marker="o", ms=3, label=g)
+    ax[0].set(xlabel="# Days Reach (training day)", ylabel="mean successful reaches",
+              title="(A) Success count learning curves")
+    ax[1].set(xlabel="# Days Reach (training day)", ylabel="success rate (success/attempts)",
+              title="(B) Success-rate learning curves")
+    for a in ax:
+        a.legend(fontsize=8)
+        a.grid(alpha=0.3)
+    fig.tight_layout()
+    fig.savefig(plot_path, dpi=120)
+    print(f"\nSaved learning-curve plot -> {plot_path}")
+
+
+def classify_one(res, unknown):
+    """Compare an unknown group against BOTH anchors; return a label + detail."""
+    vlo = diff_contrast(res, unknown, ANCHOR_LOW)   # unknown vs Box-A2
+    vhi = diff_contrast(res, unknown, ANCHOR_HIGH)  # unknown vs Box-B2
+    like_lo = vlo["p"] >= 0.05   # indistinguishable from Box-A2
+    like_hi = vhi["p"] >= 0.05   # indistinguishable from Box-B2
+    if like_hi and not like_lo:
+        verdict = "B2-like (differs from A2, matches B2)"
+    elif like_lo and not like_hi:
+        verdict = "A2-like (differs from B2, matches A2)"
+    elif like_lo and like_hi:
+        # tie: point toward whichever ratio is closer to 1 on the log scale
+        nearer = ANCHOR_HIGH if abs(vhi["coef"]) < abs(vlo["coef"]) else ANCHOR_LOW
+        verdict = f"AMBIGUOUS (matches both; numerically nearer {nearer})"
+    else:
+        verdict = "UNLIKE BOTH (differs from A2 and B2)"
+    return vlo, vhi, verdict
+
+
+def verdicts(count, rate):
+    print("\n" + "=" * 78)
+    print("VERDICTS")
+    print("=" * 78)
+
+    print("\nAnchor check — H2: Box-B2 BETTER than Box-A2 (the two anchors must differ)")
+    for label, res in [("count/level", count), ("rate/level ", rate)]:
+        c = contrast(res, gterm(ANCHOR_LOW))
+        p1 = one_sided_p_below(c)
+        tag = "SUPPORTED" if (c["coef"] < 0 and p1 < 0.05) else "not supported"
+        print(f"  [{label}] Box-B2 = {1.0 / c['eff']:.2f}x Box-A2  "
+              f"(one-sided p={p1:.4f})  -> {tag}")
+
+    if not UNKNOWNS:
+        print("\n(No unknown groups — they were merged into the anchors; "
+              "only the H2 anchor contrast applies.)")
+        return
+    print("\nClassification — is each UNKNOWN condition A2-like or B2-like?")
+    print("(ratio >1 = above that anchor; p = differs from that anchor)")
+    for u in UNKNOWNS:
+        print(f"\n  {u}:")
+        for label, res in [("count/level", count), ("rate/level ", rate)]:
+            vlo, vhi, verdict = classify_one(res, u)
+            print(f"    [{label}] vs Box-A2: {vlo['eff']:.2f}x "
+                  f"[{vlo['lo']:.2f},{vlo['hi']:.2f}] p={vlo['p']:.3f}   "
+                  f"vs Box-B2: {vhi['eff']:.2f}x [{vhi['lo']:.2f},{vhi['hi']:.2f}] "
+                  f"p={vhi['p']:.3f}")
+            print(f"                 -> {verdict}")
+    print("\n  NOTE: each unknown has ONLY 1 subject. 'Matches' means 'not statistically")
+    print("  distinguishable' — weak evidence at n=1, not proof of equivalence.")
+
+
+def main():
+    ap = argparse.ArgumentParser(description="tDCS GLM hypothesis tests")
+    ap.add_argument("--max-day", type=int, default=None,
+                    help="restrict analysis to training days 0..MAX_DAY (default: all)")
+    ap.add_argument("--merge", action="store_true",
+                    help="preset: Electrode-Box-A->Box-A2 and Right-Electrode->Box-B2")
+    ap.add_argument("--assign", type=str, default=None,
+                    help="custom merges 'UNKNOWN=TARGET,...', e.g. "
+                         "'Electrode-Box-A=Electrode-Box-B2,Right-Electrode=Electrode-Box-B2'")
+    args = ap.parse_args()
+
+    mapping = {}
+    if args.merge:
+        mapping.update(MERGE_MAP)
+    if args.assign:
+        for pair in args.assign.split(","):
+            k, v = pair.split("=")
+            mapping[k.strip()] = v.strip()
+
+    df = load(args.max_day, mapping)
+
+    global MAIN, OTHERS, UNKNOWNS
+    present = set(df["group"])
+    MAIN = [g for g in ALL_GROUPS if g in present]
+    OTHERS = [g for g in MAIN if g != REF]
+    UNKNOWNS = [g for g in CANON_UNKNOWNS if g in present]
+
+    window = f"days 0-{args.max_day}" if args.max_day is not None else "all training days (0+)"
+    tag = f"_d0-{args.max_day}" if args.max_day is not None else ""
+    tag += "_merged" if mapping else ""
+    plot_path = os.path.join(HERE, f"tdcs_learning_curves{tag}.png")
+    mode = ("assign " + ", ".join(f"{k.replace('Electrode-','')}->{v.replace('Electrode-','')}"
+                                  for k, v in mapping.items())) if mapping \
+        else "5 groups (anchors + unknowns)"
+    print(f"ANALYSIS WINDOW: {window}   |   MODE: {mode}   |   observations: {len(df)}")
+    describe(df)
+    count = fit_count_level(df)
+    rate = fit_rate_level(df)
+    learn = fit_learning_rate(df)
+    report_level("(A) LEVEL / COUNT — Poisson GEE on successful reaches",
+                 count, "incidence-rate ratio")
+    report_level("(B) LEVEL / RATE — Binomial GLM on success/attempts (cluster-robust)",
+                 rate, "odds ratio")
+    report_learning(learn)
+    report_anchor_only(df)
+    report_mixed(df)
+    verdicts(count, rate)
+    plot_curves(df, plot_path)
+    print("\nDone. See the module docstring for modeling choices and caveats.")
+
+
+if __name__ == "__main__":
+    main()

analysis/tdcs_reach_data.csv

@@ -0,0 +1,194 @@
+subject,group,day,success,total
+Vu-vuong,Naive,0,18,61
+Vu-vuong,Naive,1,35,91
+Vu-vuong,Naive,2,61,127
+Vu-vuong,Naive,3,34,146
+Vu-vuong,Naive,4,61,141
+Vu-vuong,Naive,5,37,151
+Vu-vuong,Naive,6,49,131
+Vu-vuong,Naive,7,65,149
+Vu-vuong,Naive,8,67,141
+Vu-vuong,Naive,9,73,140
+Vu-vuong,Naive,10,72,131
+Vu-vuong,Naive,11,89,158
+Vu-vuong,Naive,12,97,154
+Vu-vuong,Naive,13,93,145
+Vu-vuong,Naive,14,75,147
+Vu-vuong,Naive,15,68,142
+Vu-vuong,Naive,16,96,162
+Vu-vuong,Naive,17,68,144
+Vu-vuong,Naive,18,81,134
+Vu-vuong,Naive,19,66,144
+Vu-vuong,Naive,20,84,127
+Vu-vuong,Naive,21,66,133
+Khoai-tay-1,Electrode-Box-A,-2,1,18
+Khoai-tay-1,Electrode-Box-A,-1,3,24
+Khoai-tay-1,Electrode-Box-A,0,14,62
+Khoai-tay-1,Electrode-Box-A,1,22,83
+Khoai-tay-1,Electrode-Box-A,2,6,79
+Khoai-tay-1,Electrode-Box-A,3,28,97
+Khoai-tay-1,Electrode-Box-A,4,60,134
+Khoai-tay-1,Electrode-Box-A,5,75,138
+Khoai-tay-1,Electrode-Box-A,6,81,137
+Khoai-tay-1,Electrode-Box-A,7,78,147
+Khoai-tay-1,Electrode-Box-A,8,91,132
+Khoai-tay-1,Electrode-Box-A,9,99,146
+Khoai-tay-1,Electrode-Box-A,10,94,143
+Khoai-tay-1,Electrode-Box-A,11,110,156
+Khoai-tay-1,Electrode-Box-A,12,105,143
+Khoai-tay-1,Electrode-Box-A,13,106,153
+Khoai-tay-1,Electrode-Box-A,14,91,152
+Banh-mi-2,Electrode-Box-A2,-1,2,42
+Banh-mi-2,Electrode-Box-A2,0,25,97
+Banh-mi-2,Electrode-Box-A2,1,22,101
+Banh-mi-2,Electrode-Box-A2,2,22,119
+Banh-mi-2,Electrode-Box-A2,3,29,118
+Banh-mi-2,Electrode-Box-A2,4,27,136
+Banh-mi-2,Electrode-Box-A2,5,43,146
+Banh-mi-2,Electrode-Box-A2,6,74,146
+Banh-mi-2,Electrode-Box-A2,7,70,148
+Banh-mi-2,Electrode-Box-A2,8,65,130
+Banh-mi-2,Electrode-Box-A2,9,79,151
+Banh-mi-2,Electrode-Box-A2,10,93,152
+Egg-tart-2,Electrode-Box-A2,0,9,32
+Egg-tart-2,Electrode-Box-A2,1,2,38
+Egg-tart-2,Electrode-Box-A2,2,31,93
+Egg-tart-2,Electrode-Box-A2,3,44,101
+Egg-tart-2,Electrode-Box-A2,4,54,131
+Egg-tart-2,Electrode-Box-A2,5,84,139
+Egg-tart-2,Electrode-Box-A2,6,85,145
+Egg-tart-2,Electrode-Box-A2,7,79,143
+Egg-tart-2,Electrode-Box-A2,8,76,131
+Egg-tart-2,Electrode-Box-A2,9,88,149
+Egg-tart-2,Electrode-Box-A2,10,81,151
+Egg-tart-2,Electrode-Box-A2,11,78,152
+Egg-tart-2,Electrode-Box-A2,12,96,155
+Egg-tart-2,Electrode-Box-A2,13,84,155
+Root-beer-2,Electrode-Box-A2,0,22,74
+Root-beer-2,Electrode-Box-A2,1,31,87
+Root-beer-2,Electrode-Box-A2,2,49,134
+Root-beer-2,Electrode-Box-A2,3,31,89
+Root-beer-2,Electrode-Box-A2,4,60,140
+Root-beer-2,Electrode-Box-A2,5,84,147
+Banh-mi-1,Electrode-Box-B2,0,13,84
+Banh-mi-1,Electrode-Box-B2,1,35,86
+Banh-mi-1,Electrode-Box-B2,2,47,110
+Banh-mi-1,Electrode-Box-B2,3,65,140
+Banh-mi-1,Electrode-Box-B2,4,70,127
+Banh-mi-1,Electrode-Box-B2,5,102,142
+Banh-mi-1,Electrode-Box-B2,6,90,131
+Banh-mi-1,Electrode-Box-B2,7,109,148
+Banh-mi-1,Electrode-Box-B2,8,104,137
+Banh-mi-1,Electrode-Box-B2,9,119,150
+Banh-mi-1,Electrode-Box-B2,10,121,158
+Banh-mi-1,Electrode-Box-B2,11,121,148
+Banh-mi-1,Electrode-Box-B2,12,120,149
+Banh-mi-1,Electrode-Box-B2,13,135,154
+Egg-tart-1,Electrode-Box-B2,0,7,56
+Egg-tart-1,Electrode-Box-B2,1,16,78
+Egg-tart-1,Electrode-Box-B2,2,23,103
+Egg-tart-1,Electrode-Box-B2,3,63,120
+Egg-tart-1,Electrode-Box-B2,4,69,132
+Egg-tart-1,Electrode-Box-B2,5,83,136
+Egg-tart-1,Electrode-Box-B2,6,71,142
+Egg-tart-1,Electrode-Box-B2,7,79,138
+Egg-tart-1,Electrode-Box-B2,8,98,142
+Egg-tart-1,Electrode-Box-B2,9,89,139
+Egg-tart-1,Electrode-Box-B2,10,96,143
+Egg-tart-1,Electrode-Box-B2,11,96,148
+Egg-tart-1,Electrode-Box-B2,12,101,156
+Egg-tart-1,Electrode-Box-B2,13,103,152
+Egg-tart-1,Electrode-Box-B2,14,97,152
+Root-beer-1,Electrode-Box-B2,0,11,85
+Root-beer-1,Electrode-Box-B2,1,18,76
+Root-beer-1,Electrode-Box-B2,2,40,105
+Root-beer-1,Electrode-Box-B2,3,55,134
+Root-beer-1,Electrode-Box-B2,4,75,136
+Root-beer-1,Electrode-Box-B2,5,64,133
+Root-beer-1,Electrode-Box-B2,6,104,139
+Root-beer-1,Electrode-Box-B2,7,98,148
+Root-beer-1,Electrode-Box-B2,8,81,145
+Root-beer-1,Electrode-Box-B2,9,89,156
+Root-beer-1,Electrode-Box-B2,10,105,158
+Khoai-lang-2,Naive,0,0,0
+Khoai-lang-2,Naive,1,0,0
+Khoai-lang-2,Naive,2,10,47
+Khoai-lang-2,Naive,3,11,52
+Khoai-lang-2,Naive,4,9,56
+Khoai-lang-2,Naive,5,34,95
+Khoai-lang-2,Naive,6,21,72
+Khoai-lang-2,Naive,7,23,99
+Khoai-lang-2,Naive,8,64,136
+Khoai-lang-2,Naive,9,75,131
+Khoai-lang-2,Naive,10,63,134
+Khoai-lang-2,Naive,11,59,139
+Khoai-lang-2,Naive,12,51,129
+Khoai-lang-2,Naive,13,73,143
+Khoai-lang-2,Naive,14,82,136
+Khoai-lang-2,Naive,15,70,145
+Khoai-lang-2,Naive,16,76,135
+Khoai-lang-2,Naive,17,76,150
+Khoai-lang-2,Naive,18,63,122
+Khoai-lang-2,Naive,19,48,116
+Khoai-lang-2,Naive,20,65,134
+Khoai-lang-2,Naive,21,75,131
+Khoai-lang-2,Naive,22,98,146
+Khoai-lang-2,Naive,23,88,139
+Khoai-lang-2,Naive,24,94,148
+Khoai-lang-2,Naive,25,56,102
+Khoai-lang-2,Naive,26,75,143
+Khoai-tay-2,Naive,1,21,68
+Khoai-tay-2,Naive,2,6,79
+Khoai-tay-2,Naive,3,0,83
+Khoai-tay-2,Naive,4,28,87
+Khoai-tay-2,Naive,5,31,125
+Khoai-tay-2,Naive,6,62,144
+Khoai-tay-2,Naive,7,87,141
+Khoai-tay-2,Naive,8,105,152
+Khoai-tay-2,Naive,9,75,148
+Khoai-tay-2,Naive,10,101,149
+Khoai-tay-2,Naive,11,102,154
+Khoai-tay-2,Naive,12,95,144
+Khoai-tay-2,Naive,13,77,149
+Khoai-tay-2,Naive,14,91,153
+OM-2,Naive,-2,0,0
+OM-2,Naive,-1,5,18
+OM-2,Naive,0,1,7
+OM-2,Naive,1,11,33
+OM-2,Naive,2,19,62
+OM-2,Naive,3,29,117
+OM-2,Naive,4,73,126
+OM-2,Naive,5,53,135
+OM-2,Naive,6,73,138
+OM-2,Naive,7,80,131
+OM-2,Naive,8,91,141
+OM-2,Naive,9,90,135
+OM-2,Naive,10,95,142
+OM-2,Naive,11,60,133
+OM-2,Naive,12,58,142
+Khoai-lang-1,Right-Electrode,-4,0,0
+Khoai-lang-1,Right-Electrode,-3,2,7
+Khoai-lang-1,Right-Electrode,-1,0,0
+Khoai-lang-1,Right-Electrode,0,3,69
+Khoai-lang-1,Right-Electrode,1,18,97
+Khoai-lang-1,Right-Electrode,2,27,84
+Khoai-lang-1,Right-Electrode,3,46,121
+Khoai-lang-1,Right-Electrode,4,65,143
+Khoai-lang-1,Right-Electrode,5,76,141
+Khoai-lang-1,Right-Electrode,6,79,146
+Khoai-lang-1,Right-Electrode,7,81,153
+Khoai-lang-1,Right-Electrode,8,98,144
+Khoai-lang-1,Right-Electrode,9,101,149
+Khoai-lang-1,Right-Electrode,10,103,150
+Khoai-lang-1,Right-Electrode,11,113,154
+Khoai-lang-1,Right-Electrode,12,117,148
+Khoai-lang-1,Right-Electrode,13,114,146
+Khoai-lang-1,Right-Electrode,14,119,132
+Khoai-lang-1,Right-Electrode,15,111,156
+Khoai-lang-1,Right-Electrode,16,74,156
+Khoai-lang-1,Right-Electrode,17,109,139
+Khoai-lang-1,Right-Electrode,18,88,138
+Khoai-lang-1,Right-Electrode,19,98,140
+Khoai-lang-1,Right-Electrode,20,118,153
+Khoai-lang-1,Right-Electrode,21,109,146
+Khoai-lang-1,Right-Electrode,22,106,141

backend/Dockerfile

@@ -1,4 +1,6 @@
 FROM node:20-alpine AS base
+# Prisma migration engine requires OpenSSL
+RUN apk add --no-cache openssl
 WORKDIR /app
 COPY package*.json ./
 RUN npm ci --only=production
@@ -9,6 +11,12 @@ COPY . .
 CMD ["npm", "run", "dev"]
 
 FROM base AS prod
+# Install prisma CLI for migrate deploy at runtime
+RUN npm install prisma --save-dev
 COPY . .
+# Generate Prisma Client
 RUN npx prisma generate
-CMD ["npm", "start"]
+# Fix ownership so the node user can write engine cache
+RUN chown -R node:node /app
+USER node
+CMD ["/bin/sh", "/app/docker-entrypoint.sh"]

backend/docker-entrypoint.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+set -e
+
+echo "Running Prisma migrations..."
+npx prisma migrate deploy
+
+echo "Starting server..."
+exec node src/index.js

backend/package-lock.json

@@ -11,6 +11,7 @@
         "@prisma/client": "^5.14.0",
         "cors": "^2.8.5",
         "express": "^4.19.2",
+        "express-rate-limit": "^8.3.2",
         "express-validator": "^7.1.0",
         "helmet": "^7.1.0",
         "morgan": "^1.10.0",
@@ -2064,6 +2065,23 @@
         "url": "https://opencollective.com/express"
       }
     },
+    "node_modules/express-rate-limit": {
+      "version": "8.3.2",
+      "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-8.3.2.tgz",
+      "integrity": "sha512-77VmFeJkO0/rvimEDuUC5H30oqUC4EyOhyGccfqoLebB0oiEYfM7nwPrsDsBL1gsTpwfzX8SFy2MT3TDyRq+bg==",
+      "dependencies": {
+        "ip-address": "10.1.0"
+      },
+      "engines": {
+        "node": ">= 16"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/express-rate-limit"
+      },
+      "peerDependencies": {
+        "express": ">= 4.11"
+      }
+    },
     "node_modules/express-validator": {
       "version": "7.3.2",
       "resolved": "https://registry.npmjs.org/express-validator/-/express-validator-7.3.2.tgz",
@@ -2489,6 +2507,14 @@
       "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
     },
+    "node_modules/ip-address": {
+      "version": "10.1.0",
+      "resolved": "https://registry.npmjs.org/ip-address/-/ip-address-10.1.0.tgz",
+      "integrity": "sha512-XXADHxXmvT9+CRxhXg56LJovE+bmWnEWB78LB83VZTprKTmaC5QfruXocxzTZ2Kl0DNwKuBdlIhjL8LeY8Sf8Q==",
+      "engines": {
+        "node": ">= 12"
+      }
+    },
     "node_modules/ipaddr.js": {
       "version": "1.9.1",
       "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.1.tgz",
@@ -6396,6 +6422,14 @@
         "vary": "~1.1.2"
       }
     },
+    "express-rate-limit": {
+      "version": "8.3.2",
+      "resolved": "https://registry.npmjs.org/express-rate-limit/-/express-rate-limit-8.3.2.tgz",
+      "integrity": "sha512-77VmFeJkO0/rvimEDuUC5H30oqUC4EyOhyGccfqoLebB0oiEYfM7nwPrsDsBL1gsTpwfzX8SFy2MT3TDyRq+bg==",
+      "requires": {
+        "ip-address": "10.1.0"
+      }
+    },
     "express-validator": {
       "version": "7.3.2",
       "resolved": "https://registry.npmjs.org/express-validator/-/express-validator-7.3.2.tgz",
@@ -6697,6 +6731,11 @@
       "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
       "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
     },
+    "ip-address": {
+      "version": "10.1.0",
+      "resolved": "https://registry.npmjs.org/ip-address/-/ip-address-10.1.0.tgz",
+      "integrity": "sha512-XXADHxXmvT9+CRxhXg56LJovE+bmWnEWB78LB83VZTprKTmaC5QfruXocxzTZ2Kl0DNwKuBdlIhjL8LeY8Sf8Q=="
+    },
     "ipaddr.js": {
       "version": "1.9.1",
       "resolved": "https://registry.npmjs.org/ipaddr.js/-/ipaddr.js-1.9.1.tgz",

backend/package.json

@@ -16,6 +16,7 @@
     "@prisma/client": "^5.14.0",
     "cors": "^2.8.5",
     "express": "^4.19.2",
+    "express-rate-limit": "^8.3.2",
     "express-validator": "^7.1.0",
     "helmet": "^7.1.0",
     "morgan": "^1.10.0",
@@ -29,8 +30,9 @@
   },
   "jest": {
     "testEnvironment": "node",
-    "testMatch": ["**/tests/**/*.test.js"],
-    "setupFilesAfterFramework": [],
+    "testMatch": [
+      "**/tests/**/*.test.js"
+    ],
     "globalSetup": "./tests/setup.js",
     "globalTeardown": "./tests/teardown.js"
   }

backend/prisma/migrations/20240102000000_add_template_and_custom_fields/migration.sql

@@ -0,0 +1,5 @@
+-- Add template field to experiments (JSON array of field definitions)
+ALTER TABLE "experiments" ADD COLUMN "template" JSONB NOT NULL DEFAULT '[]';
+
+-- Add custom_fields to daily_statuses (stores values for non-builtin fields)
+ALTER TABLE "daily_statuses" ADD COLUMN "custom_fields" JSONB;

backend/prisma/migrations/20250417000000_add_subject_info/migration.sql

@@ -0,0 +1,2 @@
+ALTER TABLE "experiments" ADD COLUMN "subject_info_template" JSONB NOT NULL DEFAULT '[]';
+ALTER TABLE "animals" ADD COLUMN "subject_info" JSONB;

backend/prisma/migrations/20250419000000_add_daily_analyses/migration.sql

@@ -0,0 +1,21 @@
+CREATE TABLE "daily_analyses" (
+  "id"                TEXT      NOT NULL,
+  "daily_status_id"   TEXT      NOT NULL,
+  "created_at"        TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  "file_name"         TEXT,
+  "timestamp_col"     TEXT      NOT NULL,
+  "note_col"          TEXT      NOT NULL,
+  "classifications"   JSONB     NOT NULL,
+  "total_note_rows"   INTEGER   NOT NULL,
+  "sequence"          JSONB     NOT NULL,
+  "category_counts"   JSONB     NOT NULL,
+  "consecutive_stats" JSONB     NOT NULL,
+  "runs"              JSONB     NOT NULL,
+  CONSTRAINT "daily_analyses_pkey" PRIMARY KEY ("id")
+);
+
+ALTER TABLE "daily_analyses"
+  ADD CONSTRAINT "daily_analyses_daily_status_id_fkey"
+  FOREIGN KEY ("daily_status_id")
+  REFERENCES "daily_statuses"("id")
+  ON DELETE CASCADE ON UPDATE CASCADE;

backend/prisma/migrations/20250419010000_add_session_end_ts/migration.sql

@@ -0,0 +1 @@
+ALTER TABLE "daily_analyses" ADD COLUMN "session_end_ts" DOUBLE PRECISION;

backend/prisma/migrations/20250419020000_add_analysis_summary/migration.sql

@@ -0,0 +1 @@
+ALTER TABLE "daily_statuses" ADD COLUMN "analysis_summary" JSONB;

backend/prisma/migrations/20250423000000_add_session_files/migration.sql

@@ -0,0 +1,18 @@
+CREATE TABLE "session_files" (
+    "id"              TEXT         NOT NULL,
+    "daily_status_id" TEXT         NOT NULL,
+    "filename"        TEXT         NOT NULL,
+    "file_size"       BIGINT       NOT NULL,
+    "file_type"       TEXT,
+    "last_modified"   BIGINT,
+    "notes"           TEXT,
+    "created_at"      TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "session_files_pkey" PRIMARY KEY ("id")
+);
+
+ALTER TABLE "session_files"
+    ADD CONSTRAINT "session_files_daily_status_id_fkey"
+    FOREIGN KEY ("daily_status_id")
+    REFERENCES "daily_statuses"("id")
+    ON DELETE CASCADE ON UPDATE CASCADE;

backend/prisma/migrations/20250423010000_session_files_matching_metadata/migration.sql

@@ -0,0 +1,4 @@
+ALTER TABLE "session_files"
+    ADD COLUMN "matched_identifier"    TEXT,
+    ADD COLUMN "animal_id_string_snap" TEXT,
+    ADD COLUMN "animal_name_snap"      TEXT;

backend/prisma/migrations/20260501114346_add_animal_csv_analysis_config/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "animals" ADD COLUMN     "csv_analysis_config" JSONB;

backend/prisma/migrations/20260601000000_add_experiment_plot_config/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "experiments" ADD COLUMN     "plot_config" JSONB;

backend/prisma/schema.prisma

@@ -1,5 +1,6 @@
 generator client {
-  provider = "prisma-client-js"
+  provider      = "prisma-client-js"
+  binaryTargets = ["native", "linux-musl-openssl-3.0.x"]
 }
 
 datasource db {
@@ -8,38 +9,83 @@ datasource db {
 }
 
 model Experiment {
-  id         String   @id @default(uuid())
-  title      String
-  created_at DateTime @default(now())
-  animals    Animal[]
+  id                    String   @id @default(uuid())
+  title                 String
+  created_at            DateTime @default(now())
+  template              Json     @default("[]")
+  subject_info_template Json     @default("[]")
+  plot_config           Json?
+  animals               Animal[]
 
   @@map("experiments")
 }
 
 model Animal {
-  id               String        @id @default(uuid())
-  experiment_id    String
-  animal_id_string String
-  animal_name      String
-  experiment       Experiment    @relation(fields: [experiment_id], references: [id], onDelete: Cascade)
-  daily_statuses   DailyStatus[]
+  id                  String        @id @default(uuid())
+  experiment_id       String
+  animal_id_string    String
+  animal_name         String
+  subject_info        Json?
+  csv_analysis_config Json?
+  experiment          Experiment    @relation(fields: [experiment_id], references: [id], onDelete: Cascade)
+  daily_statuses      DailyStatus[]
 
   @@map("animals")
 }
 
 model DailyStatus {
-  id                     String   @id @default(uuid())
+  id                     String          @id @default(uuid())
   animal_id              String
-  date                   DateTime @db.Date
+  date                   DateTime        @db.Date
   experiment_description String?
   vitals                 String?
   treatment              String?
   notes                  String?
-  animal                 Animal   @relation(fields: [animal_id], references: [id], onDelete: Cascade)
+  custom_fields          Json?
+  analysis_summary       Json?
+  animal                 Animal          @relation(fields: [animal_id], references: [id], onDelete: Cascade)
+  analyses               DailyAnalysis[]
+  session_files          SessionFile[]
 
   @@map("daily_statuses")
 }
 
+model SessionFile {
+  id                    String      @id @default(uuid())
+  daily_status_id       String
+  daily_status          DailyStatus @relation(fields: [daily_status_id], references: [id], onDelete: Cascade)
+  filename              String
+  file_size             BigInt
+  file_type             String?
+  last_modified         BigInt?
+  matched_identifier    String?     // the animal ID/name substring that matched in the filename
+  animal_id_string_snap String?     // snapshot of animal.animal_id_string at registration time
+  animal_name_snap      String?     // snapshot of animal.animal_name at registration time
+  notes                 String?
+  created_at            DateTime    @default(now())
+
+  @@map("session_files")
+}
+
+model DailyAnalysis {
+  id                String      @id @default(uuid())
+  daily_status_id   String
+  daily_status      DailyStatus @relation(fields: [daily_status_id], references: [id], onDelete: Cascade)
+  created_at        DateTime    @default(now())
+  file_name         String?
+  timestamp_col     String
+  note_col          String
+  classifications   Json
+  total_note_rows   Int
+  session_end_ts    Float?
+  sequence          Json
+  category_counts   Json
+  consecutive_stats Json
+  runs              Json
+
+  @@map("daily_analyses")
+}
+
 model AuditLog {
   id         String   @id @default(uuid())
   table_name String

backend/src/app.js

@@ -0,0 +1,75 @@
+const express = require('express');
+const cors = require('cors');
+const helmet = require('helmet');
+const morgan = require('morgan');
+const rateLimit = require('express-rate-limit');
+const { globalErrorHandler } = require('./middleware/errorHandler');
+
+const experimentsRouter = require('./routes/experiments');
+const animalsRouter = require('./routes/animals');
+const dailyStatusesRouter = require('./routes/dailyStatuses');
+const auditLogsRouter = require('./routes/auditLogs');
+const analysesRouter = require('./routes/analyses');
+const sessionFilesRouter = require('./routes/sessionFiles');
+
+const app = express();
+
+// Security headers
+app.use(helmet({
+  crossOriginResourcePolicy: { policy: 'cross-origin' },
+}));
+
+// CORS — restrict to the configured frontend origin in production
+const allowedOrigin = process.env.CORS_ORIGIN || '*';
+app.use(cors({
+  origin: allowedOrigin,
+  methods: ['GET', 'POST', 'PUT', 'DELETE', 'OPTIONS'],
+  allowedHeaders: ['Content-Type', 'Authorization'],
+}));
+
+// Rate limiting — 100 requests per minute per IP on all API routes
+const apiLimiter = rateLimit({
+  windowMs: 60 * 1000,
+  max: 100,
+  standardHeaders: true,
+  legacyHeaders: false,
+  message: { error: 'Too many requests, please try again later.' },
+  skip: () => process.env.NODE_ENV === 'test',
+});
+
+app.use(express.json({ limit: '1mb' }));
+app.use(morgan(process.env.NODE_ENV === 'test' ? 'silent' : process.env.NODE_ENV === 'production' ? 'combined' : 'dev'));
+
+// Health check (no rate limit)
+app.get('/health', (req, res) => {
+  res.json({ status: 'ok', timestamp: new Date().toISOString() });
+});
+
+// DB info — returns database timezone (no rate limit)
+const prisma = require('./lib/prisma');
+app.get('/api/info', async (req, res) => {
+  try {
+    const [{ timezone }] = await prisma.$queryRaw`SELECT current_setting('TimeZone') AS timezone`;
+    res.json({ dbTimezone: timezone });
+  } catch {
+    res.json({ dbTimezone: null });
+  }
+});
+
+// Apply rate limiter to all API routes
+app.use('/api', apiLimiter);
+
+app.use('/api/experiments', experimentsRouter);
+app.use('/api/animals', animalsRouter);
+app.use('/api/daily-statuses', dailyStatusesRouter);
+app.use('/api/audit-logs', auditLogsRouter);
+app.use('/api', analysesRouter);
+app.use('/api', sessionFilesRouter);
+
+app.use((req, res) => {
+  res.status(404).json({ error: `Route ${req.method} ${req.path} not found` });
+});
+
+app.use(globalErrorHandler);
+
+module.exports = app;

backend/src/index.js

@@ -1,58 +1,13 @@
-const express = require('express');
-const cors = require('cors');
-const helmet = require('helmet');
-const morgan = require('morgan');
 const prisma = require('./lib/prisma');
-const { globalErrorHandler } = require('./middleware/errorHandler');
+const app = require('./app');
 
-const experimentsRouter = require('./routes/experiments');
-const animalsRouter = require('./routes/animals');
-const dailyStatusesRouter = require('./routes/dailyStatuses');
-const auditLogsRouter = require('./routes/auditLogs');
-
-const app = express();
 const PORT = process.env.PORT || 3001;
 
-// Security & utility middleware
-app.use(helmet());
-app.use(cors({
-  origin: process.env.CORS_ORIGIN || '*',
-  methods: ['GET', 'POST', 'PUT', 'DELETE', 'OPTIONS'],
-  allowedHeaders: ['Content-Type', 'Authorization'],
-}));
-app.use(express.json({ limit: '1mb' }));
-app.use(morgan(process.env.NODE_ENV === 'production' ? 'combined' : 'dev'));
-
-// Health check
-app.get('/health', (req, res) => {
-  res.json({ status: 'ok', timestamp: new Date().toISOString() });
-});
-
-// API routes
-app.use('/api/experiments', experimentsRouter);
-app.use('/api/animals', animalsRouter);
-app.use('/api/daily-statuses', dailyStatusesRouter);
-app.use('/api/audit-logs', auditLogsRouter);
-
-// 404 handler for unknown routes
-app.use((req, res) => {
-  res.status(404).json({ error: `Route ${req.method} ${req.path} not found` });
-});
-
-// Global error handler (must be last)
-app.use(globalErrorHandler);
-
 async function startServer() {
   try {
     await prisma.$connect();
     console.log('Database connected successfully');
-
-    // Run migrations on startup in production
-    if (process.env.NODE_ENV === 'production') {
-      const { execSync } = require('child_process');
-      execSync('npx prisma migrate deploy', { stdio: 'inherit' });
-    }
-
+    // Note: migrations are run by docker-entrypoint.sh before this process starts
     app.listen(PORT, '0.0.0.0', () => {
       console.log(`Server running on port ${PORT}`);
     });
@@ -63,5 +18,3 @@ async function startServer() {
 }
 
 startServer();
-
-module.exports = app; // export for testing

backend/src/lib/cache.js

@@ -0,0 +1,33 @@
+// Lightweight in-process TTL cache with prefix-based invalidation.
+// Single-process only — suitable for this single-container deployment.
+
+const DEFAULT_TTL_MS = 10 * 60 * 1000; // 10 minutes
+
+const store = new Map(); // key → { value, expiresAt }
+
+function set(key, value, ttlMs = DEFAULT_TTL_MS) {
+  store.set(key, { value, expiresAt: Date.now() + ttlMs });
+}
+
+function get(key) {
+  const entry = store.get(key);
+  if (!entry) return undefined;
+  if (Date.now() > entry.expiresAt) {
+    store.delete(key);
+    return undefined;
+  }
+  return entry.value;
+}
+
+function del(key) {
+  store.delete(key);
+}
+
+// Remove all keys that start with prefix — used to invalidate a whole experiment's worth of cached data.
+function delByPrefix(prefix) {
+  for (const key of store.keys()) {
+    if (key.startsWith(prefix)) store.delete(key);
+  }
+}
+
+module.exports = { set, get, del, delByPrefix };

backend/src/lib/csvConfigValidation.js

@@ -0,0 +1,51 @@
+const REQUIRED_DEFAULT_BUCKETS = ['Success', 'Failure', 'Other'];
+const ALLOWED_TYPES = new Set(['note', 'numerical']);
+
+/**
+ * Validate a csv_analysis_config payload.
+ * @param {unknown} body
+ * @returns {string|null} error message, or null if valid.
+ */
+function validateCsvConfig(body) {
+  if (body === null || typeof body !== 'object' || Array.isArray(body)) {
+    return 'Body must be an object';
+  }
+  const { buckets } = body;
+  if (!Array.isArray(buckets)) {
+    return 'buckets must be an array';
+  }
+
+  const seenNames = new Set();
+  for (const b of buckets) {
+    if (b === null || typeof b !== 'object' || Array.isArray(b)) {
+      return 'Each bucket must be an object';
+    }
+    if (typeof b.name !== 'string' || b.name.trim() === '') {
+      return 'Each bucket must have a non-empty name';
+    }
+    if (seenNames.has(b.name)) {
+      return `Duplicate bucket name: ${b.name}`;
+    }
+    seenNames.add(b.name);
+
+    if (!ALLOWED_TYPES.has(b.type)) {
+      return `Invalid type for bucket ${b.name}: ${b.type}`;
+    }
+    if (!Array.isArray(b.notes)) {
+      return `notes must be an array for bucket ${b.name}`;
+    }
+    if (!b.notes.every((n) => typeof n === 'string')) {
+      return `notes must be an array of strings for bucket ${b.name}`;
+    }
+  }
+
+  for (const required of REQUIRED_DEFAULT_BUCKETS) {
+    if (!seenNames.has(required)) {
+      return `Missing required default bucket: ${required}`;
+    }
+  }
+
+  return null;
+}
+
+module.exports = { validateCsvConfig, REQUIRED_DEFAULT_BUCKETS };

backend/src/lib/defaultTemplate.js

@@ -0,0 +1,27 @@
+/**
+ * The default daily-record template applied to every new experiment.
+ *
+ * `fieldId`     — stable UUID; used as the storage key in custom_fields.
+ *                 Builtin fields have fixed canonical UUIDs so they are
+ *                 recognised across all experiments.
+ * `key`         — human-readable slug (display / validation only)
+ * `builtin`     — true  → value stored in the dedicated DB column
+ *                 false → value stored in daily_statuses.custom_fields[fieldId]
+ * `active`      — false → hidden from forms (data preserved)
+ * `tags`        — quick-fill presets, stored per field per experiment
+ */
+const DEFAULT_TEMPLATE = [
+  { fieldId: '00000000-0000-0000-0000-000000000001', key: 'experiment_description', label: 'Experiment Description', type: 'textarea', builtin: true,  active: true, tags: [] },
+  { fieldId: '00000000-0000-0000-0000-000000000002', key: 'vitals',                 label: 'Vitals',                  type: 'text',     builtin: true,  active: true, tags: [] },
+  { fieldId: '00000000-0000-0000-0000-000000000003', key: 'treatment',              label: 'Treatment',               type: 'text',     builtin: true,  active: true, tags: [] },
+  { fieldId: '00000000-0000-0000-0000-000000000004', key: 'notes',                  label: 'Notes',                   type: 'textarea', builtin: true,  active: true, tags: [] },
+];
+
+const UUID_RE = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;
+
+function resolveTemplate(stored) {
+  if (!Array.isArray(stored) || stored.length === 0) return DEFAULT_TEMPLATE;
+  return stored;
+}
+
+module.exports = { DEFAULT_TEMPLATE, resolveTemplate, UUID_RE };

backend/src/middleware/auditMiddleware.js

@@ -21,36 +21,40 @@ function auditMiddleware(tableName, model, idParam = 'id') {
       // Attach before-state so route handlers can reference it if needed
       req._auditBefore = before;
 
-      // Wrap res.json to intercept the response
-      const originalJson = res.json.bind(res);
-      res.json = async function (data) {
-        // Only log on successful mutations
+      // Shared audit writer — called by both res.json and res.send interceptors
+      async function writeAuditLog() {
         if (res.statusCode >= 200 && res.statusCode < 300) {
           try {
             const action = req.method === 'DELETE' ? 'DELETE' : 'UPDATE';
             const after = action === 'DELETE' ? null : await model.findUnique({ where: { id: recordId } });
-
-            const changes = {
-              before,
-              after,
-            };
-
             await prisma.auditLog.create({
               data: {
                 table_name: tableName,
                 record_id: recordId,
                 action,
-                changes,
+                changes: { before, after },
               },
             });
           } catch (auditErr) {
-            // Audit failures should never block the primary response
             console.error('Audit log write failed:', auditErr.message);
           }
         }
+      }
+
+      // Wrap res.json (used by JSON-returning routes)
+      const originalJson = res.json.bind(res);
+      res.json = async function (data) {
+        await writeAuditLog();
         return originalJson(data);
       };
 
+      // Wrap res.send (used by DELETE 204 routes)
+      const originalSend = res.send.bind(res);
+      res.send = async function (data) {
+        await writeAuditLog();
+        return originalSend(data);
+      };
+
       next();
     } catch (err) {
       next(err);

backend/src/routes/analyses.js

@@ -0,0 +1,79 @@
+const router = require('express').Router();
+const prisma = require('../lib/prisma');
+
+// GET /api/daily-statuses/:statusId/analyses
+router.get('/daily-statuses/:statusId/analyses', async (req, res, next) => {
+  try {
+    const analyses = await prisma.dailyAnalysis.findMany({
+      where: { daily_status_id: req.params.statusId },
+      orderBy: { created_at: 'desc' },
+      select: {
+        id: true,
+        created_at: true,
+        file_name: true,
+        timestamp_col: true,
+        note_col: true,
+        classifications: true,
+        total_note_rows: true,
+        session_end_ts: true,
+        category_counts: true,
+        consecutive_stats: true,
+        runs: true,
+        // sequence omitted from list — fetch individually when needed
+      },
+    });
+    res.json(analyses);
+  } catch (err) { next(err); }
+});
+
+// POST /api/daily-statuses/:statusId/analyses
+router.post('/daily-statuses/:statusId/analyses', async (req, res, next) => {
+  try {
+    const status = await prisma.dailyStatus.findUnique({ where: { id: req.params.statusId } });
+    if (!status) return res.status(404).json({ error: 'Daily status not found' });
+
+    const { file_name, timestamp_col, note_col, classifications, total_note_rows,
+            session_end_ts, sequence, category_counts, consecutive_stats, runs } = req.body;
+
+    if (!timestamp_col || !note_col || classifications == null || total_note_rows == null
+        || !sequence || !category_counts || !consecutive_stats || !runs) {
+      return res.status(422).json({ error: 'Missing required analysis fields' });
+    }
+
+    const analysis = await prisma.dailyAnalysis.create({
+      data: {
+        daily_status_id:   req.params.statusId,
+        file_name:         file_name ?? null,
+        timestamp_col,
+        note_col,
+        classifications,
+        total_note_rows,
+        session_end_ts:    session_end_ts != null ? Number(session_end_ts) : null,
+        sequence,
+        category_counts,
+        consecutive_stats,
+        runs,
+      },
+    });
+    res.status(201).json(analysis);
+  } catch (err) { next(err); }
+});
+
+// GET /api/analyses/:id  (full record including sequence)
+router.get('/analyses/:id', async (req, res, next) => {
+  try {
+    const analysis = await prisma.dailyAnalysis.findUnique({ where: { id: req.params.id } });
+    if (!analysis) return res.status(404).json({ error: 'Analysis not found' });
+    res.json(analysis);
+  } catch (err) { next(err); }
+});
+
+// DELETE /api/analyses/:id
+router.delete('/analyses/:id', async (req, res, next) => {
+  try {
+    await prisma.dailyAnalysis.delete({ where: { id: req.params.id } });
+    res.status(204).send();
+  } catch (err) { next(err); }
+});
+
+module.exports = router;

backend/src/routes/animals.js

@@ -3,9 +3,10 @@ const { body, query } = require('express-validator');
 const prisma = require('../lib/prisma');
 const auditMiddleware = require('../middleware/auditMiddleware');
 const { validateRequest } = require('../middleware/errorHandler');
+const { validateCsvConfig } = require('../lib/csvConfigValidation');
 
 const animalValidation = [
-  body('experiment_id').notEmpty().withMessage('experiment_id is required').isUUID().withMessage('experiment_id must be a valid UUID'),
+  body('experiment_id').notEmpty().withMessage('experiment_id is required').matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('experiment_id must be a valid UUID'),
   body('animal_id_string').trim().notEmpty().withMessage('animal_id_string is required'),
   body('animal_name').trim().notEmpty().withMessage('animal_name is required'),
 ];
@@ -13,12 +14,13 @@ const animalValidation = [
 const animalUpdateValidation = [
   body('animal_id_string').optional().trim().notEmpty().withMessage('animal_id_string cannot be empty'),
   body('animal_name').optional().trim().notEmpty().withMessage('animal_name cannot be empty'),
+  body('subject_info').optional({ nullable: true }).isObject().withMessage('subject_info must be an object'),
 ];
 
 // GET /api/animals?experimentId=<uuid> — list for experiment
 router.get(
   '/',
-  [query('experimentId').optional().isUUID().withMessage('experimentId must be a valid UUID')],
+  [query('experimentId').optional().matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('experimentId must be a valid UUID')],
   validateRequest,
   async (req, res, next) => {
     try {
@@ -80,10 +82,11 @@ router.put(
   validateRequest,
   async (req, res, next) => {
     try {
-      const { animal_id_string, animal_name } = req.body;
+      const { animal_id_string, animal_name, subject_info } = req.body;
       const data = {};
       if (animal_id_string !== undefined) data.animal_id_string = animal_id_string;
       if (animal_name !== undefined) data.animal_name = animal_name;
+      if (subject_info !== undefined) data.subject_info = subject_info;
 
       const animal = await prisma.animal.update({
         where: { id: req.params.id },
@@ -110,4 +113,24 @@ router.delete(
   }
 );
 
+// PATCH /api/animals/:id/csv-config — replace entire CSV-analysis bucket config
+router.patch(
+  '/:id/csv-config',
+  auditMiddleware('animals', prisma.animal),
+  async (req, res, next) => {
+    try {
+      const err = validateCsvConfig(req.body);
+      if (err) return res.status(400).json({ error: err });
+
+      const animal = await prisma.animal.update({
+        where: { id: req.params.id },
+        data: { csv_analysis_config: req.body },
+      });
+      res.json(animal);
+    } catch (e) {
+      next(e);
+    }
+  }
+);
+
 module.exports = router;

backend/src/routes/auditLogs.js

@@ -7,8 +7,8 @@ const { validateRequest } = require('../middleware/errorHandler');
 router.get(
   '/',
   [
-    query('tableName').optional().isString(),
-    query('recordId').optional().isUUID().withMessage('recordId must be a valid UUID'),
+    query('tableName').optional().isIn(['experiments', 'animals', 'daily_statuses', 'audit_logs']).withMessage('tableName must be one of: experiments, animals, daily_statuses, audit_logs'),
+    query('recordId').optional().matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('recordId must be a valid UUID'),
     query('limit').optional().isInt({ min: 1, max: 200 }).withMessage('limit must be 1–200').toInt(),
     query('offset').optional().isInt({ min: 0 }).withMessage('offset must be ≥0').toInt(),
   ],

backend/src/routes/dailyStatuses.js

@@ -1,30 +1,43 @@
 const router = require('express').Router();
 const { body, query } = require('express-validator');
 const prisma = require('../lib/prisma');
+const cache = require('../lib/cache');
 const auditMiddleware = require('../middleware/auditMiddleware');
 const { validateRequest } = require('../middleware/errorHandler');
 
+// Look up which experiment a daily status belongs to, then clear all cached data for it.
+async function invalidateByStatusId(statusId) {
+  const rec = await prisma.dailyStatus.findUnique({
+    where: { id: statusId },
+    select: { animal: { select: { experiment_id: true } } },
+  });
+  const expId = rec?.animal?.experiment_id;
+  if (expId) cache.delByPrefix(`exp:${expId}:`);
+}
+
 const statusValidation = [
-  body('animal_id').notEmpty().withMessage('animal_id is required').isUUID().withMessage('animal_id must be a valid UUID'),
+  body('animal_id').notEmpty().withMessage('animal_id is required').matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('animal_id must be a valid UUID'),
   body('date').notEmpty().withMessage('date is required').isISO8601().withMessage('date must be a valid ISO 8601 date (YYYY-MM-DD)'),
-  body('experiment_description').optional().isString(),
-  body('vitals').optional().isString(),
-  body('treatment').optional().isString(),
-  body('notes').optional().isString(),
+  body('experiment_description').optional({ nullable: true }).isString(),
+  body('vitals').optional({ nullable: true }).isString(),
+  body('treatment').optional({ nullable: true }).isString(),
+  body('notes').optional({ nullable: true }).isString(),
+  body('custom_fields').optional({ nullable: true }).isObject().withMessage('custom_fields must be an object'),
 ];
 
 const statusUpdateValidation = [
   body('date').optional().isISO8601().withMessage('date must be a valid ISO 8601 date'),
-  body('experiment_description').optional().isString(),
-  body('vitals').optional().isString(),
-  body('treatment').optional().isString(),
-  body('notes').optional().isString(),
+  body('experiment_description').optional({ nullable: true }).isString(),
+  body('vitals').optional({ nullable: true }).isString(),
+  body('treatment').optional({ nullable: true }).isString(),
+  body('notes').optional({ nullable: true }).isString(),
+  body('custom_fields').optional({ nullable: true }).isObject().withMessage('custom_fields must be an object'),
 ];
 
-// GET /api/daily-statuses?animalId=<uuid> — list for animal
+// GET /api/daily-statuses?animalId=<uuid>
 router.get(
   '/',
-  [query('animalId').optional().isUUID().withMessage('animalId must be a valid UUID')],
+  [query('animalId').optional().matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('animalId must be a valid UUID')],
   validateRequest,
   async (req, res, next) => {
     try {
@@ -35,13 +48,11 @@ router.get(
         include: { animal: { select: { animal_name: true, animal_id_string: true } } },
       });
       res.json(statuses);
-    } catch (err) {
-      next(err);
-    }
+    } catch (err) { next(err); }
   }
 );
 
-// GET /api/daily-statuses/:id — get one
+// GET /api/daily-statuses/:id
 router.get('/:id', async (req, res, next) => {
   try {
     const status = await prisma.dailyStatus.findUnique({
@@ -50,15 +61,13 @@ router.get('/:id', async (req, res, next) => {
     });
     if (!status) return res.status(404).json({ error: 'Daily status not found' });
     res.json(status);
-  } catch (err) {
-    next(err);
-  }
+  } catch (err) { next(err); }
 });
 
-// POST /api/daily-statuses — create
+// POST /api/daily-statuses
 router.post('/', statusValidation, validateRequest, async (req, res, next) => {
   try {
-    const { animal_id, date, experiment_description, vitals, treatment, notes } = req.body;
+    const { animal_id, date, experiment_description, vitals, treatment, notes, custom_fields } = req.body;
     const status = await prisma.dailyStatus.create({
       data: {
         animal_id,
@@ -67,25 +76,20 @@ router.post('/', statusValidation, validateRequest, async (req, res, next) => {
         vitals,
         treatment,
         notes,
+        custom_fields: custom_fields ?? {},
       },
     });
-
     await prisma.auditLog.create({
-      data: {
-        table_name: 'daily_statuses',
-        record_id: status.id,
-        action: 'CREATE',
-        changes: { before: null, after: status },
-      },
+      data: { table_name: 'daily_statuses', record_id: status.id, action: 'CREATE', changes: { before: null, after: status } },
     });
-
+    // Invalidate cached experiment data — new status may change calendar counts and chart data
+    const animal = await prisma.animal.findUnique({ where: { id: animal_id }, select: { experiment_id: true } });
+    if (animal) cache.delByPrefix(`exp:${animal.experiment_id}:`);
     res.status(201).json(status);
-  } catch (err) {
-    next(err);
-  }
+  } catch (err) { next(err); }
 });
 
-// PUT /api/daily-statuses/:id — update
+// PUT /api/daily-statuses/:id
 router.put(
   '/:id',
   auditMiddleware('daily_statuses', prisma.dailyStatus),
@@ -93,36 +97,68 @@ router.put(
   validateRequest,
   async (req, res, next) => {
     try {
-      const { date, experiment_description, vitals, treatment, notes } = req.body;
+      const { date, experiment_description, vitals, treatment, notes, custom_fields } = req.body;
       const data = {};
-      if (date !== undefined) data.date = new Date(date);
-      if (experiment_description !== undefined) data.experiment_description = experiment_description;
-      if (vitals !== undefined) data.vitals = vitals;
-      if (treatment !== undefined) data.treatment = treatment;
-      if (notes !== undefined) data.notes = notes;
+      if (date !== undefined)                   data.date = new Date(date);
+      if (experiment_description !== undefined)  data.experiment_description = experiment_description;
+      if (vitals !== undefined)                  data.vitals = vitals;
+      if (treatment !== undefined)               data.treatment = treatment;
+      if (notes !== undefined)                   data.notes = notes;
+      if (custom_fields !== undefined)           data.custom_fields = custom_fields;
 
-      const status = await prisma.dailyStatus.update({
-        where: { id: req.params.id },
-        data,
-      });
+      const status = await prisma.dailyStatus.update({ where: { id: req.params.id }, data });
+      await invalidateByStatusId(req.params.id);
       res.json(status);
-    } catch (err) {
-      next(err);
-    }
+    } catch (err) { next(err); }
   }
 );
 
-// DELETE /api/daily-statuses/:id — delete
+// PUT /api/daily-statuses/:id/analysis-summary
+router.put('/:id/analysis-summary', async (req, res, next) => {
+  try {
+    const status = await prisma.dailyStatus.findUnique({
+      where: { id: req.params.id },
+      include: { animal: { select: { experiment_id: true } } },
+    });
+    if (!status) return res.status(404).json({ error: 'Daily status not found' });
+
+    const { counts, total, success_rate, source_analysis_id } = req.body;
+    if (!counts || total == null) {
+      return res.status(422).json({ error: 'counts and total are required' });
+    }
+
+    const summary = {
+      counts,
+      total,
+      success_rate: success_rate ?? null,
+      source_analysis_id: source_analysis_id ?? null,
+      computed_at: new Date().toISOString(),
+    };
+
+    const updated = await prisma.dailyStatus.update({
+      where: { id: req.params.id },
+      data: { analysis_summary: summary },
+    });
+    if (status.animal?.experiment_id) cache.delByPrefix(`exp:${status.animal.experiment_id}:`);
+    res.json(updated);
+  } catch (err) { next(err); }
+});
+
+// DELETE /api/daily-statuses/:id
 router.delete(
   '/:id',
   auditMiddleware('daily_statuses', prisma.dailyStatus),
   async (req, res, next) => {
     try {
+      // Resolve experiment before deleting so we can invalidate after
+      const rec = await prisma.dailyStatus.findUnique({
+        where: { id: req.params.id },
+        select: { animal: { select: { experiment_id: true } } },
+      });
       await prisma.dailyStatus.delete({ where: { id: req.params.id } });
+      if (rec?.animal?.experiment_id) cache.delByPrefix(`exp:${rec.animal.experiment_id}:`);
       res.status(204).send();
-    } catch (err) {
-      next(err);
-    }
+    } catch (err) { next(err); }
   }
 );
 

backend/src/routes/experiments.js

@@ -1,14 +1,108 @@
 const router = require('express').Router();
 const { body } = require('express-validator');
 const prisma = require('../lib/prisma');
+const cache = require('../lib/cache');
 const auditMiddleware = require('../middleware/auditMiddleware');
 const { validateRequest } = require('../middleware/errorHandler');
+const { v4: uuidv4 } = require('uuid');
+const { resolveTemplate, DEFAULT_TEMPLATE, UUID_RE } = require('../lib/defaultTemplate');
 
 const experimentValidation = [
   body('title').trim().notEmpty().withMessage('Title is required').isLength({ max: 255 }).withMessage('Title must be ≤255 characters'),
 ];
 
-// GET /api/experiments — list all
+// ── Template validation helpers ────────────────────────────────────────────────
+
+const BUILTIN_FIELD_IDS = new Set(DEFAULT_TEMPLATE.map((f) => f.fieldId));
+const BUILTIN_KEYS      = new Set(DEFAULT_TEMPLATE.map((f) => f.key));
+const VALID_TYPES       = new Set(['text', 'textarea']);
+
+function validateTemplate(template) {
+  if (!Array.isArray(template)) return 'template must be an array';
+  if (template.length > 50) return 'template may have at most 50 fields';
+
+  const seenFieldIds = new Set();
+  const seenKeys     = new Set();
+
+  for (const field of template) {
+    // ── fieldId ────────────────────────────────────────────────────────────────
+    if (!field.fieldId || !UUID_RE.test(field.fieldId))
+      return `each field must have a valid UUID fieldId (got: ${field.fieldId})`;
+    if (seenFieldIds.has(field.fieldId))
+      return `duplicate fieldId "${field.fieldId}"`;
+    seenFieldIds.add(field.fieldId);
+
+    // Builtin fields must keep their original fieldIds
+    if (BUILTIN_KEYS.has(field.key) && !BUILTIN_FIELD_IDS.has(field.fieldId))
+      return `builtin field "${field.key}" must keep its original fieldId`;
+
+    // ── key ────────────────────────────────────────────────────────────────────
+    if (!field.key || typeof field.key !== 'string') return 'each field must have a string key';
+    if (!/^[a-z0-9_]+$/.test(field.key)) return `key "${field.key}" must be lowercase alphanumeric/underscore only`;
+    if (field.key.length > 64) return `key "${field.key}" must be ≤64 characters`;
+    if (seenKeys.has(field.key)) return `duplicate key "${field.key}"`;
+    seenKeys.add(field.key);
+
+    // ── label ──────────────────────────────────────────────────────────────────
+    if (!field.label || typeof field.label !== 'string' || !field.label.trim())
+      return `field "${field.key}" must have a non-empty label`;
+    if (field.label.length > 128) return `label for "${field.key}" must be ≤128 characters`;
+
+    // ── type / active / builtin ────────────────────────────────────────────────
+    if (!VALID_TYPES.has(field.type)) return `field "${field.key}" type must be "text" or "textarea"`;
+    if (typeof field.active !== 'boolean') return `field "${field.key}" must have a boolean active flag`;
+
+    if (BUILTIN_KEYS.has(field.key) && field.builtin !== true)
+      return `field "${field.key}" is a builtin field and cannot be made non-builtin`;
+    if (!BUILTIN_KEYS.has(field.key) && field.builtin !== false)
+      return `custom field "${field.key}" must have builtin: false`;
+
+    // ── abbr / unit / width ────────────────────────────────────────────────────
+    if (field.abbr !== undefined && field.abbr !== null) {
+      if (typeof field.abbr !== 'string') return `abbr for "${field.key}" must be a string`;
+      if (field.abbr.length > 10) return `abbr for "${field.key}" must be ≤10 characters`;
+    }
+    if (field.unit !== undefined && field.unit !== null) {
+      if (typeof field.unit !== 'string') return `unit for "${field.key}" must be a string`;
+      if (field.unit.length > 10) return `unit for "${field.key}" must be ≤10 characters`;
+    }
+    if (field.width !== undefined && field.width !== null) {
+      if (!Number.isInteger(field.width) || field.width < 1 || field.width > 100)
+        return `width for "${field.key}" must be an integer between 1 and 100`;
+    }
+
+    // ── tags ───────────────────────────────────────────────────────────────────
+    if (field.tags !== undefined) {
+      if (!Array.isArray(field.tags)) return `tags for "${field.key}" must be an array`;
+      if (field.tags.length > 50) return `field "${field.key}" may have at most 50 tags`;
+      for (const tag of field.tags) {
+        if (typeof tag !== 'string' || !tag.trim()) return `tags for "${field.key}" must be non-empty strings`;
+        if (tag.length > 512) return `a tag in "${field.key}" exceeds 512 characters`;
+      }
+    }
+
+    if (field.tagsDisabled !== undefined && typeof field.tagsDisabled !== 'boolean')
+      return `tagsDisabled for "${field.key}" must be a boolean`;
+  }
+  return null;
+}
+
+/**
+ * Back-fill any missing fieldIds (handles records saved before this feature).
+ * Builtin fields get their canonical IDs; custom fields get fresh UUIDs.
+ */
+function ensureFieldIds(template) {
+  const builtinById = Object.fromEntries(DEFAULT_TEMPLATE.map((f) => [f.key, f.fieldId]));
+  return template.map((f) => ({
+    ...f,
+    fieldId: f.fieldId || (f.builtin ? builtinById[f.key] : uuidv4()),
+    tags: f.tags ?? [],   // always return tags array (empty if not yet set)
+  }));
+}
+
+// ── Experiment CRUD ────────────────────────────────────────────────────────────
+
+// GET /api/experiments
 router.get('/', async (req, res, next) => {
   try {
     const experiments = await prisma.experiment.findMany({
@@ -16,12 +110,10 @@ router.get('/', async (req, res, next) => {
       include: { _count: { select: { animals: true } } },
     });
     res.json(experiments);
-  } catch (err) {
-    next(err);
-  }
+  } catch (err) { next(err); }
 });
 
-// GET /api/experiments/:id — get one with animals
+// GET /api/experiments/:id
 router.get('/:id', async (req, res, next) => {
   try {
     const experiment = await prisma.experiment.findUnique({
@@ -29,35 +121,25 @@ router.get('/:id', async (req, res, next) => {
       include: { animals: true },
     });
     if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+    experiment.template = ensureFieldIds(resolveTemplate(experiment.template));
     res.json(experiment);
-  } catch (err) {
-    next(err);
-  }
+  } catch (err) { next(err); }
 });
 
-// POST /api/experiments — create
+// POST /api/experiments
 router.post('/', experimentValidation, validateRequest, async (req, res, next) => {
   try {
     const { title } = req.body;
     const experiment = await prisma.experiment.create({ data: { title } });
-
-    // Write CREATE audit log
     await prisma.auditLog.create({
-      data: {
-        table_name: 'experiments',
-        record_id: experiment.id,
-        action: 'CREATE',
-        changes: { before: null, after: experiment },
-      },
+      data: { table_name: 'experiments', record_id: experiment.id, action: 'CREATE', changes: { before: null, after: experiment } },
     });
-
+    experiment.template = ensureFieldIds(resolveTemplate(experiment.template));
     res.status(201).json(experiment);
-  } catch (err) {
-    next(err);
-  }
+  } catch (err) { next(err); }
 });
 
-// PUT /api/experiments/:id — update
+// PUT /api/experiments/:id
 router.put(
   '/:id',
   auditMiddleware('experiments', prisma.experiment),
@@ -66,18 +148,14 @@ router.put(
   async (req, res, next) => {
     try {
       const { title } = req.body;
-      const experiment = await prisma.experiment.update({
-        where: { id: req.params.id },
-        data: { title },
-      });
+      const experiment = await prisma.experiment.update({ where: { id: req.params.id }, data: { title } });
+      experiment.template = ensureFieldIds(resolveTemplate(experiment.template));
       res.json(experiment);
-    } catch (err) {
-      next(err);
-    }
+    } catch (err) { next(err); }
   }
 );
 
-// DELETE /api/experiments/:id — delete
+// DELETE /api/experiments/:id
 router.delete(
   '/:id',
   auditMiddleware('experiments', prisma.experiment),
@@ -85,10 +163,283 @@ router.delete(
     try {
       await prisma.experiment.delete({ where: { id: req.params.id } });
       res.status(204).send();
-    } catch (err) {
-      next(err);
-    }
+    } catch (err) { next(err); }
   }
 );
 
+// ── Subject-template validation ────────────────────────────────────────────────
+
+function validateSubjectTemplate(template) {
+  if (!Array.isArray(template)) return 'subject_info_template must be an array';
+  if (template.length > 50) return 'subject_info_template may have at most 50 fields';
+
+  const seenFieldIds = new Set();
+  const seenKeys     = new Set();
+
+  for (const field of template) {
+    if (!field.fieldId || !UUID_RE.test(field.fieldId))
+      return `each field must have a valid UUID fieldId (got: ${field.fieldId})`;
+    if (seenFieldIds.has(field.fieldId)) return `duplicate fieldId "${field.fieldId}"`;
+    seenFieldIds.add(field.fieldId);
+
+    if (!field.key || typeof field.key !== 'string') return 'each field must have a string key';
+    if (!/^[a-z0-9_]+$/.test(field.key)) return `key "${field.key}" must be lowercase alphanumeric/underscore only`;
+    if (field.key.length > 64) return `key "${field.key}" must be ≤64 characters`;
+    if (seenKeys.has(field.key)) return `duplicate key "${field.key}"`;
+    seenKeys.add(field.key);
+
+    if (!field.label || typeof field.label !== 'string' || !field.label.trim())
+      return `field "${field.key}" must have a non-empty label`;
+    if (field.label.length > 128) return `label for "${field.key}" must be ≤128 characters`;
+
+    if (!VALID_TYPES.has(field.type)) return `field "${field.key}" type must be "text" or "textarea"`;
+    if (typeof field.active !== 'boolean') return `field "${field.key}" must have a boolean active flag`;
+    if (field.builtin !== false) return `subject field "${field.key}" must have builtin: false`;
+
+    if (field.abbr !== undefined && field.abbr !== null) {
+      if (typeof field.abbr !== 'string') return `abbr for "${field.key}" must be a string`;
+      if (field.abbr.length > 10) return `abbr for "${field.key}" must be ≤10 characters`;
+    }
+    if (field.unit !== undefined && field.unit !== null) {
+      if (typeof field.unit !== 'string') return `unit for "${field.key}" must be a string`;
+      if (field.unit.length > 10) return `unit for "${field.key}" must be ≤10 characters`;
+    }
+    if (field.width !== undefined && field.width !== null) {
+      if (!Number.isInteger(field.width) || field.width < 1 || field.width > 100)
+        return `width for "${field.key}" must be an integer between 1 and 100`;
+    }
+
+    if (field.tags !== undefined) {
+      if (!Array.isArray(field.tags)) return `tags for "${field.key}" must be an array`;
+      if (field.tags.length > 50) return `field "${field.key}" may have at most 50 tags`;
+      for (const tag of field.tags) {
+        if (typeof tag !== 'string' || !tag.trim()) return `tags for "${field.key}" must be non-empty strings`;
+        if (tag.length > 512) return `a tag in "${field.key}" exceeds 512 characters`;
+      }
+    }
+
+    if (field.tagsDisabled !== undefined && typeof field.tagsDisabled !== 'boolean')
+      return `tagsDisabled for "${field.key}" must be a boolean`;
+  }
+  return null;
+}
+
+// Upper bound on the stored UI-preference blob. Sized to comfortably hold the known
+// fields plus a full hiddenSubjects list (≤500 UUIDs ≈ 20 KB) with headroom, while
+// still guarding against a client persisting an arbitrarily large object.
+const PLOT_CONFIG_MAX_BYTES = 64 * 1024;
+
+// The blob is intentionally schema-loose (clients may add display keys over time);
+// only hiddenSubjects is structurally validated since the backend reasons about it.
+function validatePlotConfig(config) {
+  if (config === null || typeof config !== 'object' || Array.isArray(config)) {
+    return 'plot_config must be an object';
+  }
+  // req.body is already JSON-parsed, so stringify cannot throw here.
+  if (Buffer.byteLength(JSON.stringify(config), 'utf8') > PLOT_CONFIG_MAX_BYTES) {
+    return 'plot_config too large';
+  }
+  if ('hiddenSubjects' in config) {
+    const hidden = config.hiddenSubjects;
+    if (!Array.isArray(hidden) || hidden.length > 500 || !hidden.every((x) => typeof x === 'string')) {
+      return 'hiddenSubjects invalid';
+    }
+  }
+  return null;
+}
+
+// ── Template endpoints ─────────────────────────────────────────────────────────
+
+// GET /api/experiments/:id/template
+router.get('/:id/template', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({
+      where: { id: req.params.id },
+      select: { id: true, template: true },
+    });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+    res.json(ensureFieldIds(resolveTemplate(experiment.template)));
+  } catch (err) { next(err); }
+});
+
+// PUT /api/experiments/:id/template
+router.put('/:id/template', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+
+    const template = req.body;
+    const validationError = validateTemplate(template);
+    if (validationError) return res.status(422).json({ error: validationError });
+
+    const before = ensureFieldIds(resolveTemplate(experiment.template));
+    const updated = await prisma.experiment.update({
+      where: { id: req.params.id },
+      data: { template },
+    });
+
+    await prisma.auditLog.create({
+      data: {
+        table_name: 'experiments',
+        record_id: experiment.id,
+        action: 'UPDATE',
+        changes: { before: { template: before }, after: { template } },
+      },
+    });
+
+    res.json(template);
+  } catch (err) { next(err); }
+});
+
+// GET /api/experiments/:id/subject-template
+router.get('/:id/subject-template', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({
+      where: { id: req.params.id },
+      select: { id: true, subject_info_template: true },
+    });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+    const tmpl = Array.isArray(experiment.subject_info_template) ? experiment.subject_info_template : [];
+    res.json(tmpl.map((f) => ({ ...f, tags: f.tags ?? [] })));
+  } catch (err) { next(err); }
+});
+
+// PUT /api/experiments/:id/subject-template
+router.put('/:id/subject-template', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+
+    const template = req.body;
+    const validationError = validateSubjectTemplate(template);
+    if (validationError) return res.status(422).json({ error: validationError });
+
+    const updated = await prisma.experiment.update({
+      where: { id: req.params.id },
+      data: { subject_info_template: template },
+    });
+
+    await prisma.auditLog.create({
+      data: {
+        table_name: 'experiments',
+        record_id: experiment.id,
+        action: 'UPDATE',
+        changes: { before: { subject_info_template: experiment.subject_info_template }, after: { subject_info_template: template } },
+      },
+    });
+
+    res.json(template);
+  } catch (err) { next(err); }
+});
+
+// PUT /api/experiments/:id/plot-config — persist UI display settings (no audit log)
+router.put('/:id/plot-config', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+
+    const config = req.body;
+    const validationError = validatePlotConfig(config);
+    if (validationError) return res.status(422).json({ error: validationError });
+
+    await prisma.experiment.update({
+      where: { id: req.params.id },
+      data: { plot_config: config },
+    });
+    res.json(config);
+  } catch (err) { next(err); }
+});
+
+// GET /api/experiments/:id/calendar?field=<fieldId|builtinKey>
+// Returns { field, days: { "YYYY-MM-DD": count } } where count = subjects with non-empty value that day.
+router.get('/:id/calendar', async (req, res, next) => {
+  try {
+    const field = req.query.field ?? '';
+    const cacheKey = `exp:${req.params.id}:cal:${field}`;
+
+    const cached = cache.get(cacheKey);
+    if (cached) return res.json(cached);
+
+    const exp = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!exp) return res.status(404).json({ error: 'Experiment not found' });
+
+    const BUILTIN_KEYS_SET = new Set(['experiment_description', 'vitals', 'treatment', 'notes']);
+    const isBuiltin = BUILTIN_KEYS_SET.has(field);
+
+    const statuses = await prisma.dailyStatus.findMany({
+      where: { animal: { experiment_id: req.params.id } },
+      select: {
+        date: true,
+        experiment_description: true,
+        vitals: true,
+        treatment: true,
+        notes: true,
+        custom_fields: true,
+      },
+    });
+
+    const days = {};
+    for (const s of statuses) {
+      const value = isBuiltin ? s[field] : s.custom_fields?.[field];
+      if (value !== null && value !== undefined && String(value).trim() !== '') {
+        const dateKey = new Date(s.date).toISOString().slice(0, 10);
+        days[dateKey] = (days[dateKey] || 0) + 1;
+      }
+    }
+
+    const result = { field, days };
+    cache.set(cacheKey, result);
+    res.json(result);
+  } catch (err) { next(err); }
+});
+
+// GET /api/experiments/:id/daily-statuses  — all statuses for all subjects, analysis_summary included
+// ?date=YYYY-MM-DD  — filter to a single day
+// ?analysisOnly=true  — only return statuses that have a saved analysis_summary (for charts)
+router.get('/:id/daily-statuses', async (req, res, next) => {
+  try {
+    const date         = req.query.date ?? '';
+    const analysisOnly = req.query.analysisOnly === 'true';
+    const cacheKey     = `exp:${req.params.id}:ds:${analysisOnly ? '1' : '0'}:${date}`;
+
+    const cached = cache.get(cacheKey);
+    if (cached) return res.json(cached);
+
+    const exp = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!exp) return res.status(404).json({ error: 'Experiment not found' });
+
+    const where = { animal: { experiment_id: req.params.id } };
+    if (date) {
+      const d    = new Date(date + 'T00:00:00.000Z');
+      const next = new Date(d); next.setUTCDate(next.getUTCDate() + 1);
+      where.date = { gte: d, lt: next };
+    }
+
+    let statuses = await prisma.dailyStatus.findMany({
+      where,
+      select: {
+        id: true,
+        animal_id: true,
+        date: true,
+        analysis_summary: true,
+        experiment_description: true,
+        vitals: true,
+        treatment: true,
+        notes: true,
+        custom_fields: true,
+      },
+      orderBy: { date: 'asc' },
+    });
+
+    // Prisma 5 has no clean IS NOT NULL filter for Json? fields; filter in JS.
+    // The result is cached so this only runs once per cache period.
+    if (analysisOnly) {
+      statuses = statuses.filter((s) => s.analysis_summary !== null);
+    }
+
+    cache.set(cacheKey, statuses);
+    res.json(statuses);
+  } catch (err) { next(err); }
+});
+
 module.exports = router;

backend/src/routes/sessionFiles.js

@@ -0,0 +1,81 @@
+const router = require('express').Router();
+const prisma = require('../lib/prisma');
+
+// POST /api/daily-statuses/:id/files  — register file metadata (batch)
+// Body: [{ filename, file_size, file_type, last_modified,
+//          matched_identifier, animal_id_string_snap, animal_name_snap, notes }, ...]
+router.post('/daily-statuses/:id/files', async (req, res, next) => {
+  try {
+    const status = await prisma.dailyStatus.findUnique({ where: { id: req.params.id } });
+    if (!status) return res.status(404).json({ error: 'Daily status not found' });
+
+    const files = req.body;
+    if (!Array.isArray(files) || files.length === 0)
+      return res.status(422).json({ error: 'Request body must be a non-empty array of file metadata' });
+
+    if (files.length > 200)
+      return res.status(422).json({ error: 'At most 200 files per request' });
+
+    for (const f of files) {
+      if (!f.filename || typeof f.filename !== 'string' || !f.filename.trim())
+        return res.status(422).json({ error: 'Each file must have a non-empty filename' });
+      if (f.file_size == null || typeof f.file_size !== 'number' || f.file_size < 0)
+        return res.status(422).json({ error: `file_size must be a non-negative number (got: ${f.file_size})` });
+    }
+
+    const created = await prisma.$transaction(
+      files.map((f) =>
+        prisma.sessionFile.create({
+          data: {
+            daily_status_id:       req.params.id,
+            filename:              f.filename.trim(),
+            file_size:             BigInt(Math.round(f.file_size)),
+            file_type:             f.file_type             ?? null,
+            last_modified:         f.last_modified != null ? BigInt(Math.round(f.last_modified)) : null,
+            matched_identifier:    f.matched_identifier    ?? null,
+            animal_id_string_snap: f.animal_id_string_snap ?? null,
+            animal_name_snap:      f.animal_name_snap      ?? null,
+            notes:                 f.notes                 ?? null,
+          },
+        })
+      )
+    );
+
+    res.status(201).json(created.map(serializeFile));
+  } catch (err) { next(err); }
+});
+
+// GET /api/daily-statuses/:id/files
+router.get('/daily-statuses/:id/files', async (req, res, next) => {
+  try {
+    const status = await prisma.dailyStatus.findUnique({ where: { id: req.params.id } });
+    if (!status) return res.status(404).json({ error: 'Daily status not found' });
+
+    const files = await prisma.sessionFile.findMany({
+      where: { daily_status_id: req.params.id },
+      orderBy: { created_at: 'asc' },
+    });
+    res.json(files.map(serializeFile));
+  } catch (err) { next(err); }
+});
+
+// DELETE /api/session-files/:id
+router.delete('/session-files/:id', async (req, res, next) => {
+  try {
+    const file = await prisma.sessionFile.findUnique({ where: { id: req.params.id } });
+    if (!file) return res.status(404).json({ error: 'Session file not found' });
+    await prisma.sessionFile.delete({ where: { id: req.params.id } });
+    res.status(204).send();
+  } catch (err) { next(err); }
+});
+
+// BigInt fields must be serialized to strings to survive JSON.stringify
+function serializeFile(f) {
+  return {
+    ...f,
+    file_size:     f.file_size.toString(),
+    last_modified: f.last_modified != null ? f.last_modified.toString() : null,
+  };
+}
+
+module.exports = router;

backend/tests/__mocks__/prisma.js

@@ -0,0 +1,37 @@
+// Shared Prisma mock — individual test files override methods as needed.
+const prismaMock = {
+  experiment: {
+    findMany: jest.fn(),
+    findUnique: jest.fn(),
+    create: jest.fn(),
+    update: jest.fn(),
+    delete: jest.fn(),
+    count: jest.fn(),
+  },
+  animal: {
+    findMany: jest.fn(),
+    findUnique: jest.fn(),
+    create: jest.fn(),
+    update: jest.fn(),
+    delete: jest.fn(),
+    count: jest.fn(),
+  },
+  dailyStatus: {
+    findMany: jest.fn(),
+    findUnique: jest.fn(),
+    create: jest.fn(),
+    update: jest.fn(),
+    delete: jest.fn(),
+    count: jest.fn(),
+  },
+  auditLog: {
+    findMany: jest.fn(),
+    findUnique: jest.fn(),
+    create: jest.fn(),
+    count: jest.fn(),
+  },
+  $connect: jest.fn(),
+  $disconnect: jest.fn(),
+};
+
+module.exports = prismaMock;

backend/tests/animals.test.js

@@ -0,0 +1,190 @@
+const request = require('supertest');
+
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+const prisma = require('../src/lib/prisma');
+const app = require('../src/app');
+
+const EXP_ID = 'bbbbbbbb-0000-0000-0000-000000000001';
+const ANIMAL = {
+  id: 'cccccccc-0000-0000-0000-000000000001',
+  experiment_id: EXP_ID,
+  animal_id_string: 'M-001',
+  animal_name: 'Whiskers',
+  _count: { daily_statuses: 0 },
+};
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('GET /api/animals', () => {
+  it('returns animals filtered by experimentId', async () => {
+    prisma.animal.findMany.mockResolvedValue([ANIMAL]);
+    const res = await request(app).get(`/api/animals?experimentId=${EXP_ID}`);
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(1);
+    expect(res.body[0].animal_id_string).toBe('M-001');
+  });
+
+  it('returns 422 for invalid UUID experimentId', async () => {
+    const res = await request(app).get('/api/animals?experimentId=not-a-uuid');
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('GET /api/animals/:id', () => {
+  it('returns animal with daily_statuses', async () => {
+    prisma.animal.findUnique.mockResolvedValue({ ...ANIMAL, daily_statuses: [] });
+    const res = await request(app).get(`/api/animals/${ANIMAL.id}`);
+    expect(res.status).toBe(200);
+    expect(res.body.animal_name).toBe('Whiskers');
+  });
+
+  it('returns 404 for unknown animal', async () => {
+    prisma.animal.findUnique.mockResolvedValue(null);
+    const res = await request(app).get('/api/animals/00000000-0000-0000-0000-000000000000');
+    expect(res.status).toBe(404);
+  });
+});
+
+describe('POST /api/animals', () => {
+  it('creates animal with UUID and writes CREATE audit log', async () => {
+    prisma.animal.create.mockResolvedValue(ANIMAL);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .post('/api/animals')
+      .send({ experiment_id: EXP_ID, animal_id_string: 'M-001', animal_name: 'Whiskers' });
+
+    expect(res.status).toBe(201);
+    expect(res.body.id).toMatch(/^[0-9a-f-]{36}$/i);
+    expect(prisma.auditLog.create).toHaveBeenCalled();
+  });
+
+  it('returns 422 when experiment_id is missing', async () => {
+    const res = await request(app)
+      .post('/api/animals')
+      .send({ animal_id_string: 'M-001', animal_name: 'Whiskers' });
+    expect(res.status).toBe(422);
+    expect(res.body.details).toEqual(
+      expect.arrayContaining([expect.objectContaining({ field: 'experiment_id' })])
+    );
+  });
+
+  it('returns 422 when experiment_id is not a UUID', async () => {
+    const res = await request(app)
+      .post('/api/animals')
+      .send({ experiment_id: 'bad-id', animal_id_string: 'M-001', animal_name: 'Whiskers' });
+    expect(res.status).toBe(422);
+  });
+
+  it('returns 422 when animal_name is missing', async () => {
+    const res = await request(app)
+      .post('/api/animals')
+      .send({ experiment_id: EXP_ID, animal_id_string: 'M-001' });
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('PUT /api/animals/:id', () => {
+  it('updates animal and writes UPDATE audit log', async () => {
+    const updated = { ...ANIMAL, animal_name: 'Mr Whiskers' };
+    prisma.animal.findUnique
+      .mockResolvedValueOnce(ANIMAL)
+      .mockResolvedValueOnce(updated);
+    prisma.animal.update.mockResolvedValue(updated);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .put(`/api/animals/${ANIMAL.id}`)
+      .send({ animal_name: 'Mr Whiskers' });
+
+    expect(res.status).toBe(200);
+    expect(res.body.animal_name).toBe('Mr Whiskers');
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'UPDATE' }) })
+    );
+  });
+});
+
+describe('DELETE /api/animals/:id', () => {
+  it('deletes animal and writes DELETE audit log', async () => {
+    prisma.animal.findUnique.mockResolvedValue(ANIMAL);
+    prisma.animal.delete.mockResolvedValue(ANIMAL);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app).delete(`/api/animals/${ANIMAL.id}`);
+    expect(res.status).toBe(204);
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'DELETE' }) })
+    );
+  });
+});
+
+describe('PATCH /api/animals/:id/csv-config', () => {
+  const VALID_CONFIG = {
+    buckets: [
+      { name: 'Success', type: 'note', notes: ['s'] },
+      { name: 'Failure', type: 'note', notes: ['f'] },
+      { name: 'Other',   type: 'note', notes: [] },
+      { name: 'Lick latency', type: 'numerical', notes: ['L25', 'L30'] },
+    ],
+  };
+
+  it('updates csv_analysis_config and writes audit log', async () => {
+    prisma.animal.findUnique.mockResolvedValue(ANIMAL);
+    prisma.animal.update.mockResolvedValue({ ...ANIMAL, csv_analysis_config: VALID_CONFIG });
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send(VALID_CONFIG);
+
+    expect(res.status).toBe(200);
+    expect(res.body.csv_analysis_config).toEqual(VALID_CONFIG);
+    expect(prisma.animal.update).toHaveBeenCalledWith({
+      where: { id: ANIMAL.id },
+      data: { csv_analysis_config: VALID_CONFIG },
+    });
+  });
+
+  it('returns 400 when buckets is missing', async () => {
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send({});
+    expect(res.status).toBe(400);
+    expect(res.body.error).toMatch(/buckets/);
+  });
+
+  it('returns 400 for empty bucket name', async () => {
+    const bad = { buckets: [...VALID_CONFIG.buckets, { name: '  ', type: 'note', notes: [] }] };
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send(bad);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 400 for duplicate names', async () => {
+    const bad = { buckets: [...VALID_CONFIG.buckets, { name: 'Success', type: 'note', notes: [] }] };
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send(bad);
+    expect(res.status).toBe(400);
+    expect(res.body.error).toMatch(/duplicate/i);
+  });
+
+  it('returns 400 for invalid type', async () => {
+    const bad = { buckets: [...VALID_CONFIG.buckets, { name: 'X', type: 'weird', notes: [] }] };
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send(bad);
+    expect(res.status).toBe(400);
+  });
+
+  it('returns 400 when missing default bucket', async () => {
+    const bad = { buckets: VALID_CONFIG.buckets.filter((b) => b.name !== 'Success') };
+    const res = await request(app)
+      .patch(`/api/animals/${ANIMAL.id}/csv-config`)
+      .send(bad);
+    expect(res.status).toBe(400);
+    expect(res.body.error).toMatch(/Success/);
+  });
+});

backend/tests/auditLogs.test.js

@@ -0,0 +1,75 @@
+const request = require('supertest');
+
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+const prisma = require('../src/lib/prisma');
+const app = require('../src/app');
+
+const LOG = {
+  id: 'ffffffff-0000-0000-0000-000000000001',
+  table_name: 'experiments',
+  record_id: 'aaaaaaaa-0000-0000-0000-000000000001',
+  action: 'UPDATE',
+  changes: { before: { title: 'Old' }, after: { title: 'New' } },
+  timestamp: new Date().toISOString(),
+};
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('GET /api/audit-logs', () => {
+  it('returns paginated logs', async () => {
+    prisma.auditLog.findMany.mockResolvedValue([LOG]);
+    prisma.auditLog.count.mockResolvedValue(1);
+
+    const res = await request(app).get('/api/audit-logs');
+    expect(res.status).toBe(200);
+    expect(res.body.logs).toHaveLength(1);
+    expect(res.body.total).toBe(1);
+    expect(res.body.logs[0].action).toBe('UPDATE');
+  });
+
+  it('filters by tableName', async () => {
+    prisma.auditLog.findMany.mockResolvedValue([LOG]);
+    prisma.auditLog.count.mockResolvedValue(1);
+
+    const res = await request(app).get('/api/audit-logs?tableName=experiments');
+    expect(res.status).toBe(200);
+    expect(prisma.auditLog.findMany).toHaveBeenCalledWith(
+      expect.objectContaining({ where: { table_name: 'experiments' } })
+    );
+  });
+
+  it('returns 422 for invalid tableName (not in allowlist)', async () => {
+    const res = await request(app).get('/api/audit-logs?tableName=users');
+    expect(res.status).toBe(422);
+  });
+
+  it('returns 422 for invalid recordId', async () => {
+    const res = await request(app).get('/api/audit-logs?recordId=not-a-uuid');
+    expect(res.status).toBe(422);
+  });
+
+  it('respects limit and offset params', async () => {
+    prisma.auditLog.findMany.mockResolvedValue([]);
+    prisma.auditLog.count.mockResolvedValue(0);
+
+    const res = await request(app).get('/api/audit-logs?limit=10&offset=20');
+    expect(res.status).toBe(200);
+    expect(res.body.limit).toBe(10);
+    expect(res.body.offset).toBe(20);
+  });
+});
+
+describe('GET /api/audit-logs/:id', () => {
+  it('returns a single log entry', async () => {
+    prisma.auditLog.findUnique.mockResolvedValue(LOG);
+    const res = await request(app).get(`/api/audit-logs/${LOG.id}`);
+    expect(res.status).toBe(200);
+    expect(res.body.action).toBe('UPDATE');
+  });
+
+  it('returns 404 for unknown log id', async () => {
+    prisma.auditLog.findUnique.mockResolvedValue(null);
+    const res = await request(app).get('/api/audit-logs/00000000-0000-0000-0000-000000000000');
+    expect(res.status).toBe(404);
+  });
+});

backend/tests/calendar.test.js

@@ -0,0 +1,131 @@
+const request = require('supertest');
+
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+jest.mock('../src/lib/cache', () => ({ get: jest.fn(() => undefined), set: jest.fn(), del: jest.fn(), delByPrefix: jest.fn() }));
+
+const prisma = require('../src/lib/prisma');
+const app = require('../src/app');
+
+const EXP_ID = 'aaaaaaaa-0000-0000-0000-000000000001';
+
+const EXPERIMENT = {
+  id: EXP_ID,
+  title: 'Calendar Test Study',
+  created_at: new Date('2024-01-01').toISOString(),
+};
+
+// Helper: build a DailyStatus record
+function makeStatus({ date, vitals = null, customFields = null }) {
+  return {
+    date: new Date(date),
+    experiment_description: null,
+    vitals,
+    treatment: null,
+    notes: null,
+    custom_fields: customFields,
+  };
+}
+
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+describe('GET /api/experiments/:id/calendar', () => {
+  it('returns 404 when experiment does not exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(null);
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=vitals`);
+    expect(res.status).toBe(404);
+    expect(res.body.error).toMatch(/not found/i);
+  });
+
+  it('returns empty days object when no statuses exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([]);
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=vitals`);
+    expect(res.status).toBe(200);
+    expect(res.body.days).toEqual({});
+    expect(res.body.field).toBe('vitals');
+  });
+
+  it('counts subjects with non-empty builtin field per day', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ date: '2026-03-10', vitals: '120/80' }),
+      makeStatus({ date: '2026-03-10', vitals: '110/70' }),
+      makeStatus({ date: '2026-03-11', vitals: '115/75' }),
+      makeStatus({ date: '2026-03-12', vitals: null }),      // null — not counted
+      makeStatus({ date: '2026-03-12', vitals: '' }),        // empty — not counted
+    ]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=vitals`);
+    expect(res.status).toBe(200);
+    expect(res.body.days).toEqual({
+      '2026-03-10': 2,
+      '2026-03-11': 1,
+    });
+  });
+
+  it('counts subjects with non-empty custom field per day', async () => {
+    const FIELD_ID = 'cccccccc-0000-0000-0000-000000000099';
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ date: '2026-04-01', customFields: { [FIELD_ID]: '320' } }),
+      makeStatus({ date: '2026-04-01', customFields: { [FIELD_ID]: '310' } }),
+      makeStatus({ date: '2026-04-01', customFields: { [FIELD_ID]: null } }),  // null — not counted
+      makeStatus({ date: '2026-04-02', customFields: { [FIELD_ID]: '315' } }),
+    ]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=${FIELD_ID}`);
+    expect(res.status).toBe(200);
+    expect(res.body.days).toEqual({
+      '2026-04-01': 2,
+      '2026-04-02': 1,
+    });
+  });
+
+  it('ignores whitespace-only custom field values', async () => {
+    const FIELD_ID = 'dddddddd-0000-0000-0000-000000000099';
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ date: '2026-04-05', customFields: { [FIELD_ID]: '   ' } }),
+      makeStatus({ date: '2026-04-05', customFields: { [FIELD_ID]: '280' } }),
+    ]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=${FIELD_ID}`);
+    expect(res.status).toBe(200);
+    expect(res.body.days).toEqual({ '2026-04-05': 1 });
+  });
+
+  it('returns days from multiple months correctly', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ date: '2026-02-15', vitals: '100/60' }),
+      makeStatus({ date: '2026-03-01', vitals: '105/65' }),
+      makeStatus({ date: '2026-03-01', vitals: '108/68' }),
+    ]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=vitals`);
+    expect(res.status).toBe(200);
+    expect(res.body.days['2026-02-15']).toBe(1);
+    expect(res.body.days['2026-03-01']).toBe(2);
+  });
+
+  it('returns field key in response body', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([]);
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar?field=treatment`);
+    expect(res.status).toBe(200);
+    expect(res.body.field).toBe('treatment');
+  });
+
+  it('handles missing field param gracefully (empty days)', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ date: '2026-04-01', vitals: 'present' }),
+    ]);
+    // No ?field= → all values undefined, nothing counted
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/calendar`);
+    expect(res.status).toBe(200);
+    expect(res.body.days).toEqual({});
+  });
+});

backend/tests/csvConfigValidation.test.js

@@ -0,0 +1,61 @@
+const { validateCsvConfig } = require('../src/lib/csvConfigValidation');
+
+const okBuckets = [
+  { name: 'Success', type: 'note', notes: ['s'] },
+  { name: 'Failure', type: 'note', notes: ['f'] },
+  { name: 'Other',   type: 'note', notes: [] },
+];
+
+describe('validateCsvConfig', () => {
+  it('accepts a valid config with the three default buckets', () => {
+    expect(validateCsvConfig({ buckets: okBuckets })).toBeNull();
+  });
+
+  it('accepts a valid config with extra note + numerical buckets', () => {
+    const buckets = [
+      ...okBuckets,
+      { name: 'Lick latency', type: 'numerical', notes: ['L25'] },
+      { name: 'Bonus',        type: 'note',      notes: ['b'] },
+    ];
+    expect(validateCsvConfig({ buckets })).toBeNull();
+  });
+
+  it('rejects when body is not an object', () => {
+    expect(validateCsvConfig(null)).toMatch(/object/i);
+    expect(validateCsvConfig('x')).toMatch(/object/i);
+  });
+
+  it('rejects when buckets is not an array', () => {
+    expect(validateCsvConfig({ buckets: 'nope' })).toMatch(/array/i);
+  });
+
+  it('rejects an empty bucket name', () => {
+    const buckets = [...okBuckets, { name: '   ', type: 'note', notes: [] }];
+    expect(validateCsvConfig({ buckets })).toMatch(/name/i);
+  });
+
+  it('rejects duplicate bucket names', () => {
+    const buckets = [...okBuckets, { name: 'Success', type: 'note', notes: [] }];
+    expect(validateCsvConfig({ buckets })).toMatch(/duplicate/i);
+  });
+
+  it('rejects an invalid type value', () => {
+    const buckets = [...okBuckets, { name: 'X', type: 'weird', notes: [] }];
+    expect(validateCsvConfig({ buckets })).toMatch(/type/i);
+  });
+
+  it('rejects when notes is not an array', () => {
+    const buckets = [...okBuckets, { name: 'X', type: 'note', notes: 'oops' }];
+    expect(validateCsvConfig({ buckets })).toMatch(/notes/i);
+  });
+
+  it('rejects when notes contains non-strings', () => {
+    const buckets = [...okBuckets, { name: 'X', type: 'note', notes: [1, 2] }];
+    expect(validateCsvConfig({ buckets })).toMatch(/notes/i);
+  });
+
+  it('rejects when a default bucket is missing', () => {
+    const buckets = okBuckets.filter((b) => b.name !== 'Success');
+    expect(validateCsvConfig({ buckets })).toMatch(/Success/);
+  });
+});

backend/tests/dailyStatuses.test.js

@@ -0,0 +1,133 @@
+const request = require('supertest');
+
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+const prisma = require('../src/lib/prisma');
+const app = require('../src/app');
+
+const ANIMAL_ID = 'dddddddd-0000-0000-0000-000000000001';
+const STATUS = {
+  id: 'eeeeeeee-0000-0000-0000-000000000001',
+  animal_id: ANIMAL_ID,
+  date: new Date('2024-06-01').toISOString(),
+  experiment_description: 'Baseline measurement',
+  vitals: 'HR 72, Temp 37.2',
+  treatment: 'Control',
+  notes: 'Healthy',
+};
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('GET /api/daily-statuses', () => {
+  it('returns statuses filtered by animalId', async () => {
+    prisma.dailyStatus.findMany.mockResolvedValue([STATUS]);
+    const res = await request(app).get(`/api/daily-statuses?animalId=${ANIMAL_ID}`);
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(1);
+    expect(res.body[0].vitals).toBe('HR 72, Temp 37.2');
+  });
+
+  it('returns 422 for invalid animalId UUID', async () => {
+    const res = await request(app).get('/api/daily-statuses?animalId=invalid');
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('GET /api/daily-statuses/:id', () => {
+  it('returns a single status entry', async () => {
+    prisma.dailyStatus.findUnique.mockResolvedValue({ ...STATUS, animal: {} });
+    const res = await request(app).get(`/api/daily-statuses/${STATUS.id}`);
+    expect(res.status).toBe(200);
+    expect(res.body.id).toBe(STATUS.id);
+  });
+
+  it('returns 404 for unknown id', async () => {
+    prisma.dailyStatus.findUnique.mockResolvedValue(null);
+    const res = await request(app).get('/api/daily-statuses/00000000-0000-0000-0000-000000000000');
+    expect(res.status).toBe(404);
+  });
+});
+
+describe('POST /api/daily-statuses', () => {
+  it('creates status and returns 201 with UUID', async () => {
+    prisma.dailyStatus.create.mockResolvedValue(STATUS);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .post('/api/daily-statuses')
+      .send({ animal_id: ANIMAL_ID, date: '2024-06-01', vitals: 'HR 72' });
+
+    expect(res.status).toBe(201);
+    expect(res.body.id).toMatch(/^[0-9a-f-]{36}$/i);
+    expect(prisma.auditLog.create).toHaveBeenCalled();
+  });
+
+  it('returns 422 when animal_id is missing', async () => {
+    const res = await request(app)
+      .post('/api/daily-statuses')
+      .send({ date: '2024-06-01' });
+    expect(res.status).toBe(422);
+    expect(res.body.details).toEqual(
+      expect.arrayContaining([expect.objectContaining({ field: 'animal_id' })])
+    );
+  });
+
+  it('returns 422 when date is missing', async () => {
+    const res = await request(app)
+      .post('/api/daily-statuses')
+      .send({ animal_id: ANIMAL_ID });
+    expect(res.status).toBe(422);
+    expect(res.body.details).toEqual(
+      expect.arrayContaining([expect.objectContaining({ field: 'date' })])
+    );
+  });
+
+  it('returns 422 when date is not a valid ISO date', async () => {
+    const res = await request(app)
+      .post('/api/daily-statuses')
+      .send({ animal_id: ANIMAL_ID, date: 'not-a-date' });
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('PUT /api/daily-statuses/:id', () => {
+  it('updates status and writes UPDATE audit log', async () => {
+    const updated = { ...STATUS, vitals: 'HR 80' };
+    prisma.dailyStatus.findUnique
+      .mockResolvedValueOnce(STATUS)
+      .mockResolvedValueOnce(updated);
+    prisma.dailyStatus.update.mockResolvedValue(updated);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .put(`/api/daily-statuses/${STATUS.id}`)
+      .send({ vitals: 'HR 80' });
+
+    expect(res.status).toBe(200);
+    expect(res.body.vitals).toBe('HR 80');
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'UPDATE' }) })
+    );
+  });
+
+  it('returns 422 when date format is invalid', async () => {
+    prisma.dailyStatus.findUnique.mockResolvedValue(STATUS);
+    const res = await request(app)
+      .put(`/api/daily-statuses/${STATUS.id}`)
+      .send({ date: 'garbage' });
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('DELETE /api/daily-statuses/:id', () => {
+  it('deletes status and writes DELETE audit log', async () => {
+    prisma.dailyStatus.findUnique.mockResolvedValue(STATUS);
+    prisma.dailyStatus.delete.mockResolvedValue(STATUS);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app).delete(`/api/daily-statuses/${STATUS.id}`);
+    expect(res.status).toBe(204);
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'DELETE' }) })
+    );
+  });
+});

backend/tests/experimentDailyStatuses.test.js

@@ -0,0 +1,166 @@
+const request = require('supertest');
+
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+// Always miss the cache in unit tests so each test exercises the real route logic.
+jest.mock('../src/lib/cache', () => ({ get: jest.fn(() => undefined), set: jest.fn(), del: jest.fn(), delByPrefix: jest.fn() }));
+
+const prisma = require('../src/lib/prisma');
+const app    = require('../src/app');
+
+const EXP_ID = 'aaaaaaaa-0000-0000-0000-000000000001';
+
+const EXPERIMENT = {
+  id: EXP_ID,
+  title: 'DS Test Study',
+  created_at: new Date('2024-01-01').toISOString(),
+};
+
+function makeStatus(overrides = {}) {
+  return {
+    id:                     overrides.id    ?? 'dddddddd-0000-0000-0000-000000000001',
+    animal_id:              overrides.animalId ?? 'bbbbbbbb-0000-0000-0000-000000000001',
+    date:                   new Date(overrides.date ?? '2026-04-01'),
+    analysis_summary:       overrides.analysis_summary ?? null,
+    experiment_description: overrides.experiment_description ?? null,
+    vitals:                 overrides.vitals  ?? null,
+    treatment:              overrides.treatment ?? null,
+    notes:                  overrides.notes  ?? null,
+    custom_fields:          overrides.custom_fields ?? {},
+  };
+}
+
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+// ── GET /api/experiments/:id/daily-statuses ────────────────────────────────────
+
+describe('GET /api/experiments/:id/daily-statuses', () => {
+  it('returns 404 when experiment does not exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(null);
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/daily-statuses`);
+    expect(res.status).toBe(404);
+    expect(res.body.error).toMatch(/not found/i);
+  });
+
+  it('returns all statuses when no filters are provided', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const statuses = [
+      makeStatus({ id: 'id-1', analysis_summary: { total: 10, counts: { Success: 8 }, success_rate: 0.8 } }),
+      makeStatus({ id: 'id-2', analysis_summary: null }),
+      makeStatus({ id: 'id-3', analysis_summary: null }),
+    ];
+    prisma.dailyStatus.findMany.mockResolvedValue(statuses);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/daily-statuses`);
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(3);
+  });
+
+  // ── analysisOnly filter — this is the scenario that caused a 500 ──────────
+
+  it('analysisOnly=true returns only statuses with non-null analysis_summary', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const summary = { total: 20, counts: { Success: 15, Failure: 5 }, success_rate: 0.75 };
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ id: 'id-1', analysis_summary: summary }),
+      makeStatus({ id: 'id-2', analysis_summary: null }),   // must be excluded
+      makeStatus({ id: 'id-3', analysis_summary: null }),   // must be excluded
+      makeStatus({ id: 'id-4', analysis_summary: summary }),
+    ]);
+
+    const res = await request(app)
+      .get(`/api/experiments/${EXP_ID}/daily-statuses?analysisOnly=true`);
+
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(2);
+    expect(res.body.every((s) => s.analysis_summary !== null)).toBe(true);
+    expect(res.body.map((s) => s.id)).toEqual(['id-1', 'id-4']);
+  });
+
+  it('analysisOnly=true returns empty array when no statuses have analysis_summary', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ id: 'id-1', analysis_summary: null }),
+      makeStatus({ id: 'id-2', analysis_summary: null }),
+    ]);
+
+    const res = await request(app)
+      .get(`/api/experiments/${EXP_ID}/daily-statuses?analysisOnly=true`);
+
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual([]);
+  });
+
+  it('analysisOnly=true does not 500 when Prisma returns mixed null / object values', async () => {
+    // This is the exact shape that caused the production 500 — the fix must not
+    // rely on a Prisma WHERE clause (which errors on Json? null filtering in v5).
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ id: 'id-null',  analysis_summary: null }),
+      makeStatus({ id: 'id-value', analysis_summary: { total: 5, counts: {}, success_rate: null } }),
+    ]);
+
+    const res = await request(app)
+      .get(`/api/experiments/${EXP_ID}/daily-statuses?analysisOnly=true`);
+
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(1);
+    expect(res.body[0].id).toBe('id-value');
+  });
+
+  it('analysisOnly=false (explicit) returns all statuses', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const statuses = [
+      makeStatus({ id: 'id-1', analysis_summary: { total: 1, counts: {}, success_rate: null } }),
+      makeStatus({ id: 'id-2', analysis_summary: null }),
+    ];
+    prisma.dailyStatus.findMany.mockResolvedValue(statuses);
+
+    const res = await request(app)
+      .get(`/api/experiments/${EXP_ID}/daily-statuses?analysisOnly=false`);
+
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(2);
+  });
+
+  // ── date filter ────────────────────────────────────────────────────────────
+
+  it('passes date range to Prisma when ?date= is provided', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([]);
+
+    await request(app)
+      .get(`/api/experiments/${EXP_ID}/daily-statuses?date=2026-04-23`);
+
+    const whereArg = prisma.dailyStatus.findMany.mock.calls[0][0].where;
+    expect(whereArg.date).toBeDefined();
+    expect(whereArg.date.gte).toEqual(new Date('2026-04-23T00:00:00.000Z'));
+  });
+
+  it('returns 200 with empty array when no statuses exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.dailyStatus.findMany.mockResolvedValue([]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/daily-statuses`);
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual([]);
+  });
+
+  it('returned records include the expected fields', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const summary = { total: 3, counts: { Success: 2 }, success_rate: 0.67 };
+    prisma.dailyStatus.findMany.mockResolvedValue([
+      makeStatus({ id: 'id-1', vitals: '120/80', analysis_summary: summary }),
+    ]);
+
+    const res = await request(app).get(`/api/experiments/${EXP_ID}/daily-statuses`);
+    expect(res.status).toBe(200);
+    const rec = res.body[0];
+    expect(rec).toMatchObject({
+      id:               'id-1',
+      vitals:           '120/80',
+      analysis_summary: summary,
+    });
+  });
+});

backend/tests/experiments.test.js

@@ -0,0 +1,184 @@
+const request = require('supertest');
+
+// Mock Prisma before importing app so the app uses the mock
+jest.mock('../src/lib/prisma', () => require('./__mocks__/prisma'));
+const prisma = require('../src/lib/prisma');
+const app = require('../src/app');
+
+const EXPERIMENT = {
+  id: 'aaaaaaaa-0000-0000-0000-000000000001',
+  title: 'Test Study',
+  created_at: new Date('2024-01-01').toISOString(),
+  _count: { animals: 0 },
+};
+
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+describe('GET /api/experiments', () => {
+  it('returns list of experiments', async () => {
+    prisma.experiment.findMany.mockResolvedValue([EXPERIMENT]);
+    const res = await request(app).get('/api/experiments');
+    expect(res.status).toBe(200);
+    expect(res.body).toHaveLength(1);
+    expect(res.body[0].title).toBe('Test Study');
+  });
+
+  it('returns empty array when no experiments', async () => {
+    prisma.experiment.findMany.mockResolvedValue([]);
+    const res = await request(app).get('/api/experiments');
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual([]);
+  });
+});
+
+describe('GET /api/experiments/:id', () => {
+  it('returns single experiment', async () => {
+    prisma.experiment.findUnique.mockResolvedValue({ ...EXPERIMENT, animals: [] });
+    const res = await request(app).get(`/api/experiments/${EXPERIMENT.id}`);
+    expect(res.status).toBe(200);
+    expect(res.body.id).toBe(EXPERIMENT.id);
+  });
+
+  it('returns 404 for unknown id', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(null);
+    const res = await request(app).get('/api/experiments/00000000-0000-0000-0000-000000000000');
+    expect(res.status).toBe(404);
+    expect(res.body.error).toMatch(/not found/i);
+  });
+});
+
+describe('POST /api/experiments', () => {
+  it('creates experiment and returns 201 with UUID', async () => {
+    prisma.experiment.create.mockResolvedValue(EXPERIMENT);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .post('/api/experiments')
+      .send({ title: 'Test Study' });
+
+    expect(res.status).toBe(201);
+    expect(res.body.id).toBe(EXPERIMENT.id);
+    expect(res.body.title).toBe('Test Study');
+    // UUID format assertion
+    expect(res.body.id).toMatch(
+      /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i
+    );
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'CREATE' }) })
+    );
+  });
+
+  it('returns 422 when title is missing', async () => {
+    const res = await request(app).post('/api/experiments').send({});
+    expect(res.status).toBe(422);
+    expect(res.body.details).toEqual(
+      expect.arrayContaining([expect.objectContaining({ field: 'title' })])
+    );
+  });
+
+  it('returns 422 when title exceeds 255 chars', async () => {
+    const res = await request(app)
+      .post('/api/experiments')
+      .send({ title: 'x'.repeat(256) });
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('PUT /api/experiments/:id', () => {
+  it('updates experiment and writes audit log', async () => {
+    const updated = { ...EXPERIMENT, title: 'Renamed Study' };
+    prisma.experiment.findUnique
+      .mockResolvedValueOnce(EXPERIMENT)   // audit middleware fetches before-state
+      .mockResolvedValueOnce(updated);     // audit middleware fetches after-state
+    prisma.experiment.update.mockResolvedValue(updated);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app)
+      .put(`/api/experiments/${EXPERIMENT.id}`)
+      .send({ title: 'Renamed Study' });
+
+    expect(res.status).toBe(200);
+    expect(res.body.title).toBe('Renamed Study');
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'UPDATE' }) })
+    );
+  });
+
+  it('returns 422 with empty title', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const res = await request(app)
+      .put(`/api/experiments/${EXPERIMENT.id}`)
+      .send({ title: '' });
+    expect(res.status).toBe(422);
+  });
+});
+
+describe('DELETE /api/experiments/:id', () => {
+  it('deletes experiment and writes DELETE audit log', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.experiment.delete.mockResolvedValue(EXPERIMENT);
+    prisma.auditLog.create.mockResolvedValue({});
+
+    const res = await request(app).delete(`/api/experiments/${EXPERIMENT.id}`);
+    expect(res.status).toBe(204);
+    expect(prisma.auditLog.create).toHaveBeenCalledWith(
+      expect.objectContaining({ data: expect.objectContaining({ action: 'DELETE' }) })
+    );
+  });
+});
+
+describe('GET /health', () => {
+  it('returns ok status', async () => {
+    const res = await request(app).get('/health');
+    expect(res.status).toBe(200);
+    expect(res.body.status).toBe('ok');
+  });
+});
+
+describe('PUT /api/experiments/:id/plot-config', () => {
+  const CONFIG = { xField: '__days__', tickStep: 2, hiddenSubjects: ['a1', 'a2'], sidebarOpen: true };
+
+  it('saves a valid config and returns it without writing an audit log', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.experiment.update.mockResolvedValue({ ...EXPERIMENT, plot_config: CONFIG });
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(CONFIG);
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual(CONFIG);
+    expect(prisma.experiment.update).toHaveBeenCalledWith({
+      where: { id: EXPERIMENT.id },
+      data: { plot_config: CONFIG },
+    });
+    expect(prisma.auditLog.create).not.toHaveBeenCalled();
+  });
+
+  it('returns 404 when the experiment does not exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(null);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(CONFIG);
+    expect(res.status).toBe(404);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects a non-object body with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send([1, 2, 3]);
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects an invalid hiddenSubjects with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send({ hiddenSubjects: [1, 2] });
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects an oversized config with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const big = { blob: 'x'.repeat(70000) };
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(big);
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+});

backend/tests/setup.js

@@ -0,0 +1,6 @@
+// Global setup — runs once before all test suites.
+// When DATABASE_URL points to a real test DB, Prisma migrations are applied here.
+// In CI/local runs without a live DB, tests use mocked Prisma via jest.mock.
+module.exports = async function () {
+  process.env.NODE_ENV = 'test';
+};

backend/tests/teardown.js

@@ -0,0 +1,3 @@
+module.exports = async function () {
+  // Graceful shutdown of any open handles
+};

docker-compose.yml

@@ -9,10 +9,13 @@ services:
       POSTGRES_USER: ${POSTGRES_USER:-expuser}
       POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-exppassword}
       POSTGRES_DB: ${POSTGRES_DB:-experiments_db}
+      TZ: America/New_York
+    command: ["postgres", "-c", "timezone=America/New_York"]
     volumes:
       - postgres_data:/var/lib/postgresql/data
-    ports:
-      - "5432:5432"
+    # Port NOT exposed to host — only reachable by backend via internal Docker network
+    expose:
+      - "5432"
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-expuser} -d ${POSTGRES_DB:-experiments_db}"]
       interval: 10s
@@ -32,13 +35,18 @@ services:
       DATABASE_URL: postgresql://${POSTGRES_USER:-expuser}:${POSTGRES_PASSWORD:-exppassword}@postgres:5432/${POSTGRES_DB:-experiments_db}
       NODE_ENV: production
       PORT: 3001
+      CORS_ORIGIN: "http://localhost:52867"
+      TZ: America/New_York
+    # Non-root user set in Dockerfile; entrypoint runs migrations then starts server
+    entrypoint: ["/bin/sh", "/app/docker-entrypoint.sh"]
     ports:
       - "3001:3001"
     healthcheck:
-      test: ["CMD-SHELL", "wget -qO- http://localhost:3001/health || exit 1"]
-      interval: 15s
+      test: ["CMD-SHELL", "wget -qO- http://127.0.0.1:3001/health || exit 1"]
+      interval: 10s
       timeout: 5s
-      retries: 5
+      retries: 10
+      start_period: 40s
 
   frontend:
     build:

docs/superpowers/plans/2026-06-01-cross-subject-plot-interactions.md

@@ -0,0 +1,628 @@
+# Cross-subject Plot Interactions Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Add a subject-visibility sidebar, legend click-to-toggle, value-ordered tooltips, and legend/sidebar hover highlight to the "Cross-subject metrics" plot.
+
+**Architecture:** Extract pure interaction logic into `src/lib/crossSubjectChart.js` (unit-tested), build a standalone presentational `SubjectSidebar` component (unit-tested with RTL), then wire shared client-side state (`hiddenSubjects`, `highlightedSubject`, `sidebarOpen`) into `ExperimentAnalysisCharts` and thread it through both Recharts `LineChart`s. Visibility is global per-subject (affects both charts).
+
+**Tech Stack:** React 18, Recharts 2.15, Jest + React Testing Library, Tailwind.
+
+**Constraints:** Frontend only — no backend/API/DB changes, nothing persisted. Do not alter the sibling `SubjectAnalysisCharts` or the existing controls (X axis, Color by, tick step, per-chart customize bars, Y-metric selector).
+
+---
+
+### Task 1: Pure interaction helpers
+
+**Files:**
+- Create: `frontend/src/lib/crossSubjectChart.js`
+- Test: `frontend/tests/crossSubjectChart.test.js`
+
+- [ ] **Step 1: Write the failing tests**
+
+```js
+// frontend/tests/crossSubjectChart.test.js
+import {
+  sortPayloadByValueDesc,
+  toggleInSet,
+  setIdsHidden,
+  groupVisibilityState,
+  groupLines,
+} from '../src/lib/crossSubjectChart';
+
+describe('sortPayloadByValueDesc', () => {
+  it('sorts by value descending and drops null/undefined values', () => {
+    const payload = [
+      { dataKey: 'a', value: 40 },
+      { dataKey: 'b', value: null },
+      { dataKey: 'c', value: 92 },
+      { dataKey: 'd', value: 78 },
+    ];
+    expect(sortPayloadByValueDesc(payload).map((p) => p.dataKey)).toEqual(['c', 'd', 'a']);
+  });
+  it('returns [] for non-array input', () => {
+    expect(sortPayloadByValueDesc(undefined)).toEqual([]);
+  });
+  it('does not mutate the input array', () => {
+    const payload = [{ dataKey: 'a', value: 1 }, { dataKey: 'b', value: 2 }];
+    sortPayloadByValueDesc(payload);
+    expect(payload.map((p) => p.dataKey)).toEqual(['a', 'b']);
+  });
+});
+
+describe('toggleInSet', () => {
+  it('adds a missing id and removes a present id, returning a new Set', () => {
+    const a = new Set(['x']);
+    const added = toggleInSet(a, 'y');
+    expect([...added].sort()).toEqual(['x', 'y']);
+    expect(added).not.toBe(a);
+    const removed = toggleInSet(added, 'x');
+    expect([...removed]).toEqual(['y']);
+  });
+});
+
+describe('setIdsHidden', () => {
+  it('adds all ids when hidden=true', () => {
+    expect([...setIdsHidden(new Set(['a']), ['b', 'c'], true)].sort()).toEqual(['a', 'b', 'c']);
+  });
+  it('removes all ids when hidden=false', () => {
+    expect([...setIdsHidden(new Set(['a', 'b', 'c']), ['b', 'c'], false)]).toEqual(['a']);
+  });
+  it('returns a new Set', () => {
+    const s = new Set();
+    expect(setIdsHidden(s, ['a'], true)).not.toBe(s);
+  });
+});
+
+describe('groupVisibilityState', () => {
+  it("returns 'all' when none of the ids are hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set())).toBe('all');
+  });
+  it("returns 'none' when all ids are hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set(['a', 'b']))).toBe('none');
+  });
+  it("returns 'some' when a subset is hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set(['a']))).toBe('some');
+  });
+  it("returns 'none' for an empty group", () => {
+    expect(groupVisibilityState([], new Set())).toBe('none');
+  });
+});
+
+describe('groupLines', () => {
+  it('groups by .group preserving first-seen group order and within-group order', () => {
+    const lines = [
+      { id: '1', group: 'B' },
+      { id: '2', group: 'A' },
+      { id: '3', group: 'B' },
+    ];
+    const out = groupLines(lines);
+    expect(out.map((g) => g.group)).toEqual(['B', 'A']);
+    expect(out[0].subjects.map((s) => s.id)).toEqual(['1', '3']);
+  });
+  it("uses '—' for lines with no group", () => {
+    expect(groupLines([{ id: '1' }])[0].group).toBe('—');
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `cd frontend && npx jest tests/crossSubjectChart.test.js`
+Expected: FAIL — cannot find module `../src/lib/crossSubjectChart`.
+
+- [ ] **Step 3: Write the implementation**
+
+```js
+// frontend/src/lib/crossSubjectChart.js
+// Pure helpers for the cross-subject metrics plot interactions. No React, no I/O.
+
+// Sort a Recharts tooltip payload by numeric value descending, dropping entries
+// whose value is null/undefined. Returns a NEW array (does not mutate input).
+export function sortPayloadByValueDesc(payload) {
+  if (!Array.isArray(payload)) return [];
+  return payload
+    .filter((p) => p && p.value != null)
+    .slice()
+    .sort((a, b) => b.value - a.value);
+}
+
+// Toggle an id's membership in a Set, returning a NEW Set.
+export function toggleInSet(set, id) {
+  const next = new Set(set);
+  if (next.has(id)) next.delete(id);
+  else next.add(id);
+  return next;
+}
+
+// Add (hidden=true) or remove (hidden=false) a list of ids from a hidden-set.
+// Returns a NEW Set.
+export function setIdsHidden(set, ids, hidden) {
+  const next = new Set(set);
+  for (const id of ids) {
+    if (hidden) next.add(id);
+    else next.delete(id);
+  }
+  return next;
+}
+
+// Tri-state for a group checkbox given which subject ids are hidden.
+// 'all' = all visible, 'none' = all hidden, 'some' = mixed.
+export function groupVisibilityState(subjectIds, hiddenSet) {
+  if (subjectIds.length === 0) return 'none';
+  const hiddenCount = subjectIds.filter((id) => hiddenSet.has(id)).length;
+  if (hiddenCount === 0) return 'all';
+  if (hiddenCount === subjectIds.length) return 'none';
+  return 'some';
+}
+
+// Group chart "lines" by their .group field, preserving first-seen group order
+// and line order within each group. Returns [{ group, subjects: [line...] }].
+export function groupLines(lines) {
+  const order = [];
+  const byGroup = new Map();
+  for (const line of lines) {
+    const g = line.group ?? '—';
+    if (!byGroup.has(g)) { byGroup.set(g, []); order.push(g); }
+    byGroup.get(g).push(line);
+  }
+  return order.map((group) => ({ group, subjects: byGroup.get(group) }));
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `cd frontend && npx jest tests/crossSubjectChart.test.js`
+Expected: PASS — all describe blocks green.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/crossSubjectChart.js frontend/tests/crossSubjectChart.test.js
+git commit -m "feat(frontend): pure helpers for cross-subject plot interactions"
+```
+
+---
+
+### Task 2: SubjectSidebar component
+
+**Files:**
+- Create: `frontend/src/components/SubjectSidebar.jsx`
+- Test: `frontend/tests/SubjectSidebar.test.jsx`
+
+- [ ] **Step 1: Write the failing tests**
+
+```jsx
+// frontend/tests/SubjectSidebar.test.jsx
+import React from 'react';
+import { render, screen, fireEvent, within } from '@testing-library/react';
+import { SubjectSidebar } from '../src/components/SubjectSidebar';
+
+const LINES = [
+  { id: 'a1', name: 'Mouse-A1', group: 'Group A', color: '#111' },
+  { id: 'a2', name: 'Mouse-A2', group: 'Group A', color: '#222' },
+  { id: 'b1', name: 'Mouse-B1', group: 'Group B', color: '#333' },
+];
+
+function setup(overrides = {}) {
+  const props = {
+    lines: LINES,
+    hiddenSubjects: new Set(),
+    onToggleSubject: jest.fn(),
+    onToggleGroup: jest.fn(),
+    onShowAll: jest.fn(),
+    onHighlight: jest.fn(),
+    ...overrides,
+  };
+  render(<SubjectSidebar {...props} />);
+  return props;
+}
+
+it('renders each group header with its subject count', () => {
+  setup();
+  expect(screen.getByText('Group A')).toBeInTheDocument();
+  expect(screen.getByText('Group B')).toBeInTheDocument();
+  expect(screen.getByText('(2)')).toBeInTheDocument();
+  expect(screen.getByText('(1)')).toBeInTheDocument();
+});
+
+it('renders a subject checkbox per subject, checked when visible', () => {
+  setup({ hiddenSubjects: new Set(['a2']) });
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(true);
+  expect(screen.getByLabelText('Mouse-A2').checked).toBe(false);
+});
+
+it('calls onToggleSubject with the id when a subject checkbox is clicked', () => {
+  const { onToggleSubject } = setup();
+  fireEvent.click(screen.getByLabelText('Mouse-A1'));
+  expect(onToggleSubject).toHaveBeenCalledWith('a1');
+});
+
+it('shows the group checkbox as indeterminate when the group is mixed', () => {
+  setup({ hiddenSubjects: new Set(['a1']) });
+  const groupCheckbox = screen.getByLabelText(/Group A/);
+  expect(groupCheckbox.indeterminate).toBe(true);
+  expect(groupCheckbox.checked).toBe(false);
+});
+
+it('checks the group checkbox when all members are visible', () => {
+  setup();
+  expect(screen.getByLabelText(/Group A/).checked).toBe(true);
+});
+
+it('calls onToggleGroup with the group ids and hidden=true when an all-visible group is clicked', () => {
+  const { onToggleGroup } = setup();
+  fireEvent.click(screen.getByLabelText(/Group A/));
+  expect(onToggleGroup).toHaveBeenCalledWith(['a1', 'a2'], true);
+});
+
+it('hides the Show all link when nothing is hidden, shows it otherwise', () => {
+  const { rerender } = render(
+    <SubjectSidebar lines={LINES} hiddenSubjects={new Set()}
+      onToggleSubject={() => {}} onToggleGroup={() => {}}
+      onShowAll={() => {}} onHighlight={() => {}} />,
+  );
+  expect(screen.queryByText('Show all')).toBeNull();
+  rerender(
+    <SubjectSidebar lines={LINES} hiddenSubjects={new Set(['a1'])}
+      onToggleSubject={() => {}} onToggleGroup={() => {}}
+      onShowAll={() => {}} onHighlight={() => {}} />,
+  );
+  expect(screen.getByText('Show all')).toBeInTheDocument();
+});
+
+it('calls onShowAll when the Show all link is clicked', () => {
+  const { onShowAll } = setup({ hiddenSubjects: new Set(['a1']) });
+  fireEvent.click(screen.getByText('Show all'));
+  expect(onShowAll).toHaveBeenCalled();
+});
+
+it('calls onHighlight on subject row hover enter/leave', () => {
+  const { onHighlight } = setup();
+  const row = screen.getByLabelText('Mouse-A1').closest('label');
+  fireEvent.mouseEnter(row);
+  expect(onHighlight).toHaveBeenCalledWith('a1');
+  fireEvent.mouseLeave(row);
+  expect(onHighlight).toHaveBeenCalledWith(null);
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `cd frontend && npx jest tests/SubjectSidebar.test.jsx`
+Expected: FAIL — cannot find module `../src/components/SubjectSidebar`.
+
+- [ ] **Step 3: Write the implementation**
+
+Note: the group checkbox's accessible name comes from the group `<span>` text inside its `<label>`, so `getByLabelText(/Group A/)` matches it; subject checkboxes are matched by their name text. The group `<label>` text includes the count, so its accessible name is e.g. "Group A (2)" — `/Group A/` regex still matches.
+
+```jsx
+// frontend/src/components/SubjectSidebar.jsx
+import React from 'react';
+import { groupLines, groupVisibilityState } from '../lib/crossSubjectChart';
+
+// Presentational panel listing subjects grouped by their group, with per-subject
+// and per-group visibility checkboxes. All state lives in the parent; this component
+// only renders and calls handlers.
+export function SubjectSidebar({
+  lines, hiddenSubjects, onToggleSubject, onToggleGroup, onShowAll, onHighlight,
+}) {
+  const groups = groupLines(lines);
+  const anyHidden = lines.some((l) => hiddenSubjects.has(l.id));
+
+  return (
+    <div className="w-[210px] shrink-0 border-l border-gray-100 pl-3">
+      <div className="flex items-center justify-between mb-2">
+        <span className="text-xs font-semibold text-gray-500 uppercase tracking-wide">Subjects</span>
+        {anyHidden && (
+          <button type="button" onClick={onShowAll}
+            className="text-xs text-indigo-500 hover:text-indigo-700">Show all</button>
+        )}
+      </div>
+      <div className="space-y-3 max-h-[320px] overflow-y-auto pr-1">
+        {groups.map(({ group, subjects }) => {
+          const ids = subjects.map((s) => s.id);
+          const state = groupVisibilityState(ids, hiddenSubjects);
+          return (
+            <div key={group}>
+              <label className="flex items-center gap-1.5 text-xs font-medium text-gray-600 cursor-pointer">
+                <input type="checkbox"
+                  checked={state === 'all'}
+                  ref={(el) => { if (el) el.indeterminate = state === 'some'; }}
+                  onChange={() => onToggleGroup(ids, state === 'all')}
+                  className="accent-indigo-500" />
+                <span className="truncate">{group}</span>
+                <span className="text-gray-400">({subjects.length})</span>
+              </label>
+              <div className="mt-1 space-y-0.5 pl-1">
+                {subjects.map((s) => (
+                  <label key={s.id}
+                    onMouseEnter={() => onHighlight(s.id)}
+                    onMouseLeave={() => onHighlight(null)}
+                    className="flex items-center gap-1.5 text-xs text-gray-600 cursor-pointer hover:bg-gray-50 rounded px-1 py-0.5">
+                    <input type="checkbox"
+                      checked={!hiddenSubjects.has(s.id)}
+                      onChange={() => onToggleSubject(s.id)}
+                      className="accent-indigo-500" />
+                    <span className="inline-block w-2.5 h-2.5 rounded-full shrink-0"
+                      style={{ backgroundColor: s.color }} />
+                    <span className="truncate">{s.name}</span>
+                  </label>
+                ))}
+              </div>
+            </div>
+          );
+        })}
+      </div>
+    </div>
+  );
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `cd frontend && npx jest tests/SubjectSidebar.test.jsx`
+Expected: PASS — all tests green.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/components/SubjectSidebar.jsx frontend/tests/SubjectSidebar.test.jsx
+git commit -m "feat(frontend): add SubjectSidebar visibility panel"
+```
+
+---
+
+### Task 3: Wire state, sidebar, and behaviors into ExperimentAnalysisCharts
+
+**Files:**
+- Modify: `frontend/src/components/AnalysisCharts.jsx` (`ExperimentAnalysisCharts`, lines ~446–641; imports at top)
+- Test: `frontend/tests/ExperimentAnalysisCharts.test.jsx` (create)
+
+- [ ] **Step 1: Add imports**
+
+At the top of `frontend/src/components/AnalysisCharts.jsx`, add after the existing `date-fns` import:
+
+```jsx
+import { SubjectSidebar } from './SubjectSidebar';
+import { sortPayloadByValueDesc, toggleInSet, setIdsHidden } from '../lib/crossSubjectChart';
+```
+
+- [ ] **Step 2: Add shared state and handlers**
+
+In `ExperimentAnalysisCharts`, immediately after the existing `const [tickStep, setTickStep] = useState(1);` line (~454), add:
+
+```jsx
+  // Cross-subject interaction state (client-only; global across both charts)
+  const [sidebarOpen,        setSidebarOpen]        = useState(false);
+  const [hiddenSubjects,     setHiddenSubjects]     = useState(() => new Set());
+  const [highlightedSubject, setHighlightedSubject] = useState(null);
+
+  const toggleHidden = (id)          => setHiddenSubjects((prev) => toggleInSet(prev, id));
+  const toggleGroup  = (ids, hidden) => setHiddenSubjects((prev) => setIdsHidden(prev, ids, hidden));
+  const showAll      = ()            => setHiddenSubjects(new Set());
+```
+
+- [ ] **Step 3: Update the `ExpTooltip` to order rows by value descending**
+
+Replace the existing `ExpTooltip` function (~518–533) with:
+
+```jsx
+  function ExpTooltip({ active, payload, label, unit = '' }) {
+    if (!active || !payload?.length) return null;
+    const rows = sortPayloadByValueDesc(payload);
+    return (
+      <div className="bg-white border border-gray-200 rounded shadow-sm px-3 py-2 text-xs space-y-0.5 max-h-48 overflow-y-auto">
+        <p className="font-semibold text-gray-700 mb-1">{label}</p>
+        {rows.map((p) => {
+          const line = lines.find((l) => l.id === p.dataKey);
+          return (
+            <p key={p.dataKey} style={{ color: p.stroke }}>
+              {line?.name ?? p.dataKey}{line?.group && line.group !== '—' ? ` (${line.group})` : ''}: {p.value}{unit}
+            </p>
+          );
+        })}
+      </div>
+    );
+  }
+```
+
+- [ ] **Step 4: Add the sidebar toggle button to the global controls row**
+
+In the global-controls `<div className="flex items-center flex-wrap gap-3">` block, immediately after the `<TickStepControl ... />` line (~556), add:
+
+```jsx
+        {hasData && (
+          <button type="button" onClick={() => setSidebarOpen((o) => !o)}
+            className={[
+              'text-xs px-2 py-0.5 rounded border transition-colors ml-auto',
+              sidebarOpen
+                ? 'bg-gray-100 border-gray-300 text-gray-700'
+                : 'bg-white border-gray-200 text-gray-500 hover:text-gray-700 hover:border-gray-300',
+            ].join(' ')}>
+            {sidebarOpen ? '◂ Subjects' : '▸ Subjects'}
+          </button>
+        )}
+```
+
+Note: `hasData` is declared at ~509 (`const hasData = lines.length > 0;`), before the `return`, so it is in scope here.
+
+- [ ] **Step 5: Wrap the charts in a flex row with the sidebar**
+
+Replace the `{hasData && (` fragment opener and its closing for the charts block. The current structure is:
+
+```jsx
+      {hasData && (
+        <>
+          {/* Chart 1 — counts */}
+          <div> ... </div>
+          {/* Chart 2 — success rate */}
+          <div> ... </div>
+        </>
+      )}
+```
+
+Change ONLY the wrapper (keep both chart `<div>` blocks exactly as they are between the markers):
+
+```jsx
+      {hasData && (
+        <div className="flex gap-3 items-start">
+          <div className="flex-1 min-w-0 space-y-5">
+            {/* Chart 1 — counts */}
+            {/* ...unchanged chart 1 <div> ... */}
+            {/* Chart 2 — success rate */}
+            {/* ...unchanged chart 2 <div> ... */}
+          </div>
+          {sidebarOpen && (
+            <SubjectSidebar
+              lines={lines}
+              hiddenSubjects={hiddenSubjects}
+              onToggleSubject={toggleHidden}
+              onToggleGroup={toggleGroup}
+              onShowAll={showAll}
+              onHighlight={setHighlightedSubject}
+            />
+          )}
+        </div>
+      )}
+```
+
+`min-w-0` on the chart column lets the flex child shrink so `ResponsiveContainer` re-flows when the sidebar is open.
+
+- [ ] **Step 6: Add legend handlers and per-line hide/highlight to BOTH charts**
+
+In the **counts** chart, replace the `<Legend ... />` (~602–603) with:
+
+```jsx
+                <Legend wrapperStyle={{ fontSize: 11 }}
+                  formatter={(value) => lines.find((l) => l.id === value)?.name ?? value}
+                  onClick={(o) => toggleHidden(o.dataKey)}
+                  onMouseEnter={(o) => setHighlightedSubject(o.dataKey)}
+                  onMouseLeave={() => setHighlightedSubject(null)} />
+```
+
+and replace its `lines.map(...)` `<Line>` block (~604–608) with:
+
+```jsx
+                {lines.map((l) => (
+                  <Line key={l.id} type="monotone" dataKey={l.id} name={l.id}
+                    stroke={l.color}
+                    strokeWidth={highlightedSubject === l.id ? 3.5 : 2}
+                    hide={hiddenSubjects.has(l.id)}
+                    dot={{ r: 3 }} activeDot={{ r: 5 }}
+                    connectNulls isAnimationActive={false} />
+                ))}
+```
+
+In the **success-rate** chart, make the identical replacements for its `<Legend ... />` (~627–628) and its `lines.map(...)` `<Line>` block (~629–633) — same two snippets above.
+
+- [ ] **Step 7: Write a smoke test for the wiring**
+
+```jsx
+// frontend/tests/ExperimentAnalysisCharts.test.jsx
+import React from 'react';
+import { render, screen, fireEvent } from '@testing-library/react';
+
+// recharts uses ResizeObserver (absent in jsdom); stub all used pieces as passthroughs.
+jest.mock('recharts', () => {
+  const Pass = ({ children }) => <div>{children}</div>;
+  return {
+    ResponsiveContainer: Pass, LineChart: Pass, Line: () => null,
+    XAxis: () => null, YAxis: () => null, CartesianGrid: () => null,
+    Tooltip: () => null, Legend: () => null,
+  };
+});
+
+import { ExperimentAnalysisCharts } from '../src/components/AnalysisCharts';
+
+const ANIMALS = [
+  { id: 'a1', animal_name: 'Mouse-A1', subject_info: { grp: 'Group A' } },
+  { id: 'b1', animal_name: 'Mouse-B1', subject_info: { grp: 'Group B' } },
+];
+const STATUSES = [
+  { animal_id: 'a1', date: '2026-01-01', analysis_summary: { total: 10, success_rate: 0.5, counts: { Success: 5 } } },
+  { animal_id: 'b1', date: '2026-01-01', analysis_summary: { total: 8, success_rate: 0.25, counts: { Success: 2 } } },
+];
+const SUBJECT_TEMPLATE = [{ fieldId: 'grp', label: 'Group', active: true }];
+const DAILY_TEMPLATE = [];
+
+function renderChart() {
+  render(
+    <ExperimentAnalysisCharts
+      animals={ANIMALS}
+      experimentStatuses={STATUSES}
+      subjectTemplate={SUBJECT_TEMPLATE}
+      dailyTemplate={DAILY_TEMPLATE}
+    />,
+  );
+}
+
+it('toggles the subject sidebar open and closed', () => {
+  renderChart();
+  expect(screen.queryByText('Subjects')).toBeNull(); // closed: panel header not rendered
+  fireEvent.click(screen.getByText('▸ Subjects'));
+  // panel header "Subjects" + both subjects now visible
+  expect(screen.getByText('Subjects')).toBeInTheDocument();
+  expect(screen.getByLabelText('Mouse-A1')).toBeInTheDocument();
+  expect(screen.getByLabelText('Mouse-B1')).toBeInTheDocument();
+  fireEvent.click(screen.getByText('◂ Subjects'));
+  expect(screen.queryByText('Subjects')).toBeNull();
+});
+
+it('unchecking a subject in the sidebar persists across re-render', () => {
+  renderChart();
+  fireEvent.click(screen.getByText('▸ Subjects'));
+  const cb = screen.getByLabelText('Mouse-A1');
+  expect(cb.checked).toBe(true);
+  fireEvent.click(cb);
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(false);
+  // hiding one subject reveals the Show all link
+  expect(screen.getByText('Show all')).toBeInTheDocument();
+});
+```
+
+Note: the controls header `<h2>` text is "Cross-subject metrics"; the sidebar panel header text is "Subjects". They are distinct, so `queryByText('Subjects')` is null until the panel opens.
+
+- [ ] **Step 8: Run the smoke test to verify it passes**
+
+Run: `cd frontend && npx jest tests/ExperimentAnalysisCharts.test.jsx`
+Expected: PASS — both tests green.
+
+- [ ] **Step 9: Run the full frontend test suite to confirm no regressions**
+
+Run: `cd frontend && npm test`
+Expected: PASS — all existing suites plus the three new files green.
+
+- [ ] **Step 10: Build to confirm no syntax/compile errors**
+
+Run: `cd frontend && npm run build`
+Expected: Vite build succeeds with no errors.
+
+- [ ] **Step 11: Commit**
+
+```bash
+git add frontend/src/components/AnalysisCharts.jsx frontend/tests/ExperimentAnalysisCharts.test.jsx
+git commit -m "feat(frontend): subject sidebar, legend toggle/highlight, ordered tooltip on cross-subject plot"
+```
+
+---
+
+## Manual Verification (after Task 3)
+
+On the `ExperimentDetail` page for an experiment with animals and saved analysis metrics:
+
+- [ ] `▸ Subjects` button toggles the sidebar; charts re-flow narrower while open.
+- [ ] Unchecking a subject removes its line from BOTH charts; its legend entry greys out and stays clickable.
+- [ ] Re-checking (sidebar) or clicking the greyed legend entry restores the line in both charts.
+- [ ] Group checkbox toggles all members; shows indeterminate (–) when the group is mixed.
+- [ ] "Show all" appears only when something is hidden and clears all hidden state.
+- [ ] Clicking a legend entry in either chart toggles that subject in both.
+- [ ] Hover tooltip lists subjects highest-value-first, matching their vertical order.
+- [ ] Hovering a legend entry OR a sidebar row thickens that subject's line in both charts; leaving restores it.
+- [ ] Existing controls still work: X axis, Color by, tick step, per-chart customize (size/Y range/X zoom/X-field), Y-metric selector. Sibling "Session metrics over time" chart is unchanged.
+
+## Self-Review Notes
+
+- **Spec coverage:** sidebar + groups + per-subject/per-group checkboxes (Task 2, Task 3 wiring); global visibility via `hiddenSubjects` (Task 1 `toggleInSet`/`setIdsHidden`, Task 3); legend click toggle (Task 3 Step 6); value-ordered tooltip (Task 1 `sortPayloadByValueDesc`, Task 3 Step 3); legend + sidebar hover highlight via `highlightedSubject` + `strokeWidth` (Task 2 onHighlight, Task 3 Steps 2/6). All four behaviors covered.
+- **Naming consistency:** `toggleHidden`, `toggleGroup`, `showAll`, `setHighlightedSubject`, `hiddenSubjects`, `highlightedSubject`, `sidebarOpen` used identically across Task 2 props and Task 3 wiring.
+- **No DB/API:** all state is `useState` in the component; no imports from `api/`.

docs/superpowers/plans/2026-06-01-persist-cross-subject-plot-config.md

@@ -0,0 +1,678 @@
+# Persist Cross-subject Plot Config Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Persist the "Cross-subject metrics" plot's display settings per experiment in the database, hydrating on load and auto-saving (debounced) on change.
+
+**Architecture:** Add a nullable `plot_config` JSONB column to `experiments` (Prisma). Expose `PUT /api/experiments/:id/plot-config` (validated, no audit log). On the frontend, pure helpers (`serializePlotConfig`/`readPlotConfig`) translate between React state and the stored blob; `ExperimentAnalysisCharts` initializes its state from the saved config and debounce-saves changes.
+
+**Tech Stack:** Postgres + Prisma 5, Express + express-validator, Jest + supertest (backend), React 18 + Recharts 2.15, Jest + React Testing Library (frontend).
+
+**Constraints:** Follow the existing `subject_info_template` route/migration pattern. No audit-log writes for plot-config. Do not change `SubjectAnalysisCharts`, the template/subject-template routes, or any existing behavior. Migration is additive and nullable — existing experiments load with defaults.
+
+---
+
+### Task 1: Backend — column, migration, route, validator, tests
+
+**Files:**
+- Modify: `backend/prisma/schema.prisma` (model `Experiment`)
+- Create: `backend/prisma/migrations/20260601000000_add_experiment_plot_config/migration.sql`
+- Modify: `backend/src/routes/experiments.js` (add validator near other validators; add route after the `PUT /:id/subject-template` handler, ~line 309)
+- Test: `backend/tests/experiments.test.js` (add a describe block)
+
+- [ ] **Step 1: Write the failing tests**
+
+Add this block to the end of `backend/tests/experiments.test.js` (it uses the file's existing `request`, `prisma` mock, `EXPERIMENT`, and `beforeEach(jest.clearAllMocks)`):
+
+```js
+describe('PUT /api/experiments/:id/plot-config', () => {
+  const CONFIG = { xField: '__days__', tickStep: 2, hiddenSubjects: ['a1', 'a2'], sidebarOpen: true };
+
+  it('saves a valid config and returns it without writing an audit log', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    prisma.experiment.update.mockResolvedValue({ ...EXPERIMENT, plot_config: CONFIG });
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(CONFIG);
+    expect(res.status).toBe(200);
+    expect(res.body).toEqual(CONFIG);
+    expect(prisma.experiment.update).toHaveBeenCalledWith({
+      where: { id: EXPERIMENT.id },
+      data: { plot_config: CONFIG },
+    });
+    expect(prisma.auditLog.create).not.toHaveBeenCalled();
+  });
+
+  it('returns 404 when the experiment does not exist', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(null);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(CONFIG);
+    expect(res.status).toBe(404);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects a non-object body with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send([1, 2, 3]);
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects an invalid hiddenSubjects with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send({ hiddenSubjects: [1, 2] });
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+
+  it('rejects an oversized config with 422', async () => {
+    prisma.experiment.findUnique.mockResolvedValue(EXPERIMENT);
+    const big = { blob: 'x'.repeat(20000) };
+    const res = await request(app).put(`/api/experiments/${EXPERIMENT.id}/plot-config`).send(big);
+    expect(res.status).toBe(422);
+    expect(prisma.experiment.update).not.toHaveBeenCalled();
+  });
+});
+```
+
+- [ ] **Step 2: Run the tests to verify they fail**
+
+Run: `cd backend && npx jest tests/experiments.test.js -t "plot-config"`
+Expected: FAIL — route returns 404/route not found (no handler yet), assertions fail.
+
+- [ ] **Step 3: Add the Prisma column**
+
+In `backend/prisma/schema.prisma`, in `model Experiment`, add a `plot_config` field (place it after `subject_info_template`):
+
+```prisma
+model Experiment {
+  id                    String   @id @default(uuid())
+  title                 String
+  created_at            DateTime @default(now())
+  template              Json     @default("[]")
+  subject_info_template Json     @default("[]")
+  plot_config           Json?
+  animals               Animal[]
+
+  @@map("experiments")
+}
+```
+
+- [ ] **Step 4: Create the migration file**
+
+Create `backend/prisma/migrations/20260601000000_add_experiment_plot_config/migration.sql`:
+
+```sql
+-- AlterTable
+ALTER TABLE "experiments" ADD COLUMN     "plot_config" JSONB;
+```
+
+- [ ] **Step 5: Regenerate the Prisma client**
+
+Run: `cd backend && npx prisma generate`
+Expected: "Generated Prisma Client" with no errors (no DB connection required).
+
+- [ ] **Step 6: Add the validator and route**
+
+In `backend/src/routes/experiments.js`, add this validator function alongside the other validators (e.g. right after `validateSubjectTemplate`, before the routes that use it):
+
+```js
+function validatePlotConfig(config) {
+  if (config === null || typeof config !== 'object' || Array.isArray(config)) {
+    return 'plot_config must be an object';
+  }
+  let size;
+  try { size = JSON.stringify(config).length; } catch { return 'plot_config must be serializable'; }
+  if (size > 16384) return 'plot_config too large';
+  if ('hiddenSubjects' in config) {
+    const h = config.hiddenSubjects;
+    if (!Array.isArray(h) || h.length > 500 || !h.every((x) => typeof x === 'string')) {
+      return 'hiddenSubjects invalid';
+    }
+  }
+  return null;
+}
+```
+
+Then add this route immediately after the `PUT /:id/subject-template` handler (after its closing `});`, ~line 309):
+
+```js
+// PUT /api/experiments/:id/plot-config — persist UI display settings (no audit log)
+router.put('/:id/plot-config', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+
+    const config = req.body;
+    const validationError = validatePlotConfig(config);
+    if (validationError) return res.status(422).json({ error: validationError });
+
+    await prisma.experiment.update({
+      where: { id: req.params.id },
+      data: { plot_config: config },
+    });
+    res.json(config);
+  } catch (err) { next(err); }
+});
+```
+
+- [ ] **Step 7: Run the tests to verify they pass**
+
+Run: `cd backend && npx jest tests/experiments.test.js -t "plot-config"`
+Expected: PASS — all 5 new tests green.
+
+- [ ] **Step 8: Run the full backend suite (no regressions)**
+
+Run: `cd backend && npm test`
+Expected: PASS — all suites green (note any pre-existing failures unrelated to this change).
+
+- [ ] **Step 9: Commit**
+
+```bash
+git add backend/prisma/schema.prisma backend/prisma/migrations/20260601000000_add_experiment_plot_config backend/src/routes/experiments.js backend/tests/experiments.test.js
+git commit -m "feat(backend): persist per-experiment plot_config via PUT /:id/plot-config"
+```
+
+---
+
+### Task 2: Frontend — serialize/read pure helpers
+
+**Files:**
+- Modify: `frontend/src/lib/crossSubjectChart.js` (append two functions + two private helpers)
+- Test: `frontend/tests/crossSubjectChart.test.js` (append describe blocks)
+
+- [ ] **Step 1: Write the failing tests**
+
+Append to `frontend/tests/crossSubjectChart.test.js`. First add the two new names to the existing import at the top of the file — change the import to also include `serializePlotConfig, readPlotConfig`:
+
+```js
+import {
+  sortPayloadByValueDesc,
+  toggleInSet,
+  setIdsHidden,
+  groupVisibilityState,
+  groupLines,
+  serializePlotConfig,
+  readPlotConfig,
+} from '../src/lib/crossSubjectChart';
+```
+
+Then append these describe blocks at the end of the file:
+
+```js
+describe('serializePlotConfig', () => {
+  const STATE = {
+    xField: '__days__', groupBy: 'g1', tickStep: 2, metric: 'Success',
+    hiddenSubjects: new Set(['b', 'a']), sidebarOpen: true,
+    counts: { height: 220, yMin: '0', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: 'f2' },
+    rate:   { height: 160, yMin: '', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: null },
+  };
+
+  it('produces a plain JSON object with hiddenSubjects as a sorted array', () => {
+    const out = serializePlotConfig(STATE);
+    expect(out.hiddenSubjects).toEqual(['a', 'b']);
+    expect(out.sidebarOpen).toBe(true);
+    expect(out.xField).toBe('__days__');
+    expect(out.metric).toBe('Success');
+    expect(out.counts).toEqual({ height: 220, yMin: '0', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: 'f2' });
+    expect(out.rate.xFieldOverride).toBeNull();
+  });
+
+  it('round-trips through readPlotConfig (values preserved)', () => {
+    const back = readPlotConfig(serializePlotConfig(STATE));
+    expect(back.xField).toBe('__days__');
+    expect(back.groupBy).toBe('g1');
+    expect(back.tickStep).toBe(2);
+    expect(back.hiddenSubjects).toEqual(['a', 'b']);
+    expect(back.sidebarOpen).toBe(true);
+    expect(back.counts.height).toBe(220);
+    expect(back.counts.xFieldOverride).toBe('f2');
+  });
+});
+
+describe('readPlotConfig', () => {
+  it('returns safe defaults for null', () => {
+    const c = readPlotConfig(null);
+    expect(c.hiddenSubjects).toEqual([]);
+    expect(c.sidebarOpen).toBe(false);
+    expect(c.xField).toBeUndefined();
+    expect(c.counts.yMin).toBe('');
+    expect(c.counts.xFieldOverride).toBeNull();
+  });
+
+  it('returns safe defaults for a non-object', () => {
+    expect(readPlotConfig([1, 2]).hiddenSubjects).toEqual([]);
+    expect(readPlotConfig('nope').sidebarOpen).toBe(false);
+  });
+
+  it('filters non-string hiddenSubjects and ignores wrong-typed fields', () => {
+    const c = readPlotConfig({ hiddenSubjects: ['a', 5, 'b'], tickStep: 'x', sidebarOpen: 'yes' });
+    expect(c.hiddenSubjects).toEqual(['a', 'b']);
+    expect(c.tickStep).toBeUndefined();
+    expect(c.sidebarOpen).toBe(false);
+  });
+
+  it('does not throw on malformed nested chart settings', () => {
+    expect(() => readPlotConfig({ counts: 'bad', rate: [] })).not.toThrow();
+    const c = readPlotConfig({ counts: 'bad' });
+    expect(c.counts.yMin).toBe('');
+    expect(c.counts.height).toBeUndefined();
+  });
+});
+```
+
+- [ ] **Step 2: Run the tests to verify they fail**
+
+Run: `cd frontend && npx jest tests/crossSubjectChart.test.js`
+Expected: FAIL — `serializePlotConfig`/`readPlotConfig` are not exported.
+
+- [ ] **Step 3: Implement the helpers**
+
+Append to `frontend/src/lib/crossSubjectChart.js`:
+
+```js
+// ── Plot config (de)serialization ───────────────────────────────────────────────
+// Translate between ExperimentAnalysisCharts React state and the stored JSONB blob.
+// readPlotConfig is defensive: it never throws and fills safe defaults for missing
+// or malformed input (unknown keys are ignored).
+
+function snapshotChart(s = {}) {
+  return {
+    height:         s.height,
+    yMin:           s.yMin ?? '',
+    yMax:           s.yMax ?? '',
+    xZoomMin:       s.xZoomMin ?? '',
+    xZoomMax:       s.xZoomMax ?? '',
+    xFieldOverride: s.xFieldOverride ?? null,
+  };
+}
+
+export function serializePlotConfig(state) {
+  const { xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen, counts, rate } = state;
+  return {
+    xField,
+    groupBy,
+    tickStep,
+    metric,
+    hiddenSubjects: [...(hiddenSubjects ?? [])].sort(),
+    sidebarOpen: !!sidebarOpen,
+    counts: snapshotChart(counts),
+    rate:   snapshotChart(rate),
+  };
+}
+
+function readChart(c) {
+  const o = c && typeof c === 'object' && !Array.isArray(c) ? c : {};
+  const str = (v) => (typeof v === 'string' ? v : '');
+  return {
+    height:         Number.isFinite(o.height) ? o.height : undefined,
+    yMin:           str(o.yMin),
+    yMax:           str(o.yMax),
+    xZoomMin:       str(o.xZoomMin),
+    xZoomMax:       str(o.xZoomMax),
+    xFieldOverride: typeof o.xFieldOverride === 'string' ? o.xFieldOverride : null,
+  };
+}
+
+export function readPlotConfig(raw) {
+  const c = raw && typeof raw === 'object' && !Array.isArray(raw) ? raw : {};
+  return {
+    xField:   typeof c.xField === 'string' ? c.xField : undefined,
+    groupBy:  typeof c.groupBy === 'string' ? c.groupBy : undefined,
+    tickStep: Number.isFinite(c.tickStep) ? c.tickStep : undefined,
+    metric:   typeof c.metric === 'string' ? c.metric : undefined,
+    hiddenSubjects: Array.isArray(c.hiddenSubjects) ? c.hiddenSubjects.filter((x) => typeof x === 'string') : [],
+    sidebarOpen: c.sidebarOpen === true,
+    counts: readChart(c.counts),
+    rate:   readChart(c.rate),
+  };
+}
+```
+
+- [ ] **Step 4: Run the tests to verify they pass**
+
+Run: `cd frontend && npx jest tests/crossSubjectChart.test.js`
+Expected: PASS — all helper tests (including the new ones) green.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/crossSubjectChart.js frontend/tests/crossSubjectChart.test.js
+git commit -m "feat(frontend): serialize/read helpers for plot config"
+```
+
+---
+
+### Task 3: Frontend — hook refactor, API method, chart wiring, page props
+
+**Files:**
+- Modify: `frontend/src/api/client.js` (add `savePlotConfig` to `experimentsApi`, ~line 35)
+- Modify: `frontend/src/components/AnalysisCharts.jsx` (`useChartSettings` ~line 92; imports ~line 1; `ExperimentAnalysisCharts` ~line 448)
+- Modify: `frontend/src/pages/ExperimentDetail.jsx` (the `<ExperimentAnalysisCharts ... />` usage, ~line 365)
+- Test: `frontend/tests/ExperimentAnalysisCharts.test.jsx` (add hydration + save tests)
+
+- [ ] **Step 1: Add the API client method**
+
+In `frontend/src/api/client.js`, inside the `experimentsApi` object, add after the `updateSubjectTemplate` line (~line 35):
+
+```js
+  savePlotConfig: (id, config) => api.put(`/experiments/${id}/plot-config`, config).then((r) => r.data),
+```
+
+- [ ] **Step 2: Refactor `useChartSettings` to accept initial values and expose a snapshot**
+
+In `frontend/src/components/AnalysisCharts.jsx`, replace the `useChartSettings` function (currently starting `function useChartSettings(defaultHeight) {` at ~line 92, through its `return {...}`/closing `}`) with this version. It adds an `initial` parameter (seeding the useState defaults) and a `snapshot` memo; everything else is unchanged:
+
+```js
+function useChartSettings(defaultHeight, initial = {}) {
+  const [expanded,       setExpanded]       = useState(false);
+  const [height,         setHeight]         = useState(initial.height ?? defaultHeight);
+  const [yMin,           setYMin]           = useState(initial.yMin ?? '');
+  const [yMax,           setYMax]           = useState(initial.yMax ?? '');
+  const [xZoomMin,       setXZoomMin]       = useState(initial.xZoomMin ?? '');
+  const [xZoomMax,       setXZoomMax]       = useState(initial.xZoomMax ?? '');
+  const [xFieldOverride, setXFieldOverride] = useState(initial.xFieldOverride ?? null); // null → use parent's xField
+
+  const yDomain = useMemo(() => [
+    yMin !== '' ? parseFloat(yMin) : 'auto',
+    yMax !== '' ? parseFloat(yMax) : 'auto',
+  ], [yMin, yMax]);
+
+  const xDomain = useMemo(() => {
+    const hasMin = xZoomMin !== '';
+    const hasMax = xZoomMax !== '';
+    if (!hasMin && !hasMax) return null;
+    return [hasMin ? parseFloat(xZoomMin) : 'dataMin', hasMax ? parseFloat(xZoomMax) : 'dataMax'];
+  }, [xZoomMin, xZoomMax]);
+
+  const isDirty = yMin !== '' || yMax !== '' || xZoomMin !== '' || xZoomMax !== ''
+    || xFieldOverride !== null || height !== defaultHeight;
+
+  const snapshot = useMemo(
+    () => ({ height, yMin, yMax, xZoomMin, xZoomMax, xFieldOverride }),
+    [height, yMin, yMax, xZoomMin, xZoomMax, xFieldOverride],
+  );
+
+  function reset() {
+    setHeight(defaultHeight);
+    setYMin(''); setYMax('');
+    setXZoomMin(''); setXZoomMax('');
+    setXFieldOverride(null);
+  }
+
+  return {
+    expanded, setExpanded,
+    height, setHeight,
+    yMin, setYMin, yMax, setYMax,
+    xZoomMin, setXZoomMin, xZoomMax, setXZoomMax,
+    xFieldOverride, setXFieldOverride,
+    yDomain, xDomain, isDirty, reset, snapshot,
+  };
+}
+```
+
+- [ ] **Step 3: Update imports in `AnalysisCharts.jsx`**
+
+At the top of the file, change the React import to include `useRef`, and add the new helper imports to the existing `crossSubjectChart` import. The React import becomes:
+
+```jsx
+import React, { useState, useMemo, useEffect, useRef } from 'react';
+```
+
+And the `crossSubjectChart` import becomes:
+
+```jsx
+import { sortPayloadByValueDesc, toggleInSet, setIdsHidden, serializePlotConfig, readPlotConfig } from '../lib/crossSubjectChart';
+```
+
+- [ ] **Step 4: Add the two new props and config-driven initialization to `ExperimentAnalysisCharts`**
+
+Change the component signature (~line 448) to accept the new props:
+
+```jsx
+export function ExperimentAnalysisCharts({ animals, experimentStatuses, subjectTemplate, dailyTemplate, plotConfig, onPersistConfig }) {
+```
+
+Then, immediately after the `const defaultGroup = ...` line (~line 452) and BEFORE the existing `const [groupBy, ...]` state declarations, insert the once-only config read:
+
+```jsx
+  // Read the saved config exactly once (component only mounts after the experiment loads).
+  const initialConfigRef = useRef(null);
+  if (initialConfigRef.current === null) initialConfigRef.current = readPlotConfig(plotConfig);
+  const initialConfig = initialConfigRef.current;
+```
+
+Now replace the existing five state declarations (`groupBy`, `metric`, `xField`, `tickStep`, and the `sidebarOpen`/`hiddenSubjects` declarations) so each is seeded from `initialConfig`. Replace these lines:
+
+```jsx
+  const [groupBy,  setGroupBy]  = useState(defaultGroup);
+  const [metric,   setMetric]   = useState('total');
+  const [xField,   setXField]   = useState(() => defaultXField(xAxisFields));
+  const [tickStep, setTickStep] = useState(1);
+
+  // Cross-subject interaction state (client-only; global across both charts)
+  const [sidebarOpen,        setSidebarOpen]        = useState(false);
+  const [hiddenSubjects,     setHiddenSubjects]     = useState(() => new Set());
+  const [highlightedSubject, setHighlightedSubject] = useState(null);
+```
+
+with:
+
+```jsx
+  const [groupBy,  setGroupBy]  = useState(initialConfig.groupBy ?? defaultGroup);
+  const [metric,   setMetric]   = useState(initialConfig.metric ?? 'total');
+  const [xField,   setXField]   = useState(() => initialConfig.xField ?? defaultXField(xAxisFields));
+  const [tickStep, setTickStep] = useState(initialConfig.tickStep ?? 1);
+
+  // Cross-subject interaction state (client-only; global across both charts)
+  const [sidebarOpen,        setSidebarOpen]        = useState(initialConfig.sidebarOpen);
+  const [hiddenSubjects,     setHiddenSubjects]     = useState(() => new Set(initialConfig.hiddenSubjects));
+  const [highlightedSubject, setHighlightedSubject] = useState(null);
+```
+
+And seed the two per-chart hooks from `initialConfig`. Replace:
+
+```jsx
+  const countsS = useChartSettings(200);
+  const rateS   = useChartSettings(160);
+```
+
+with:
+
+```jsx
+  const countsS = useChartSettings(200, initialConfig.counts);
+  const rateS   = useChartSettings(160, initialConfig.rate);
+```
+
+- [ ] **Step 5: Add the serialized config + debounced auto-save**
+
+Immediately after the `const countsS`/`const rateS` lines (and the `toggleHidden`/`toggleGroup`/`showAll` handlers which are just above them), add the serialization memo, save-state, and debounced-save effect. Insert this block right after the `const rateS = ...` line:
+
+```jsx
+  // ── Persist display settings (debounced auto-save) ────────────────────────────
+  const [saveState, setSaveState] = useState('idle'); // 'idle' | 'saving' | 'saved' | 'error'
+
+  const currentConfig = useMemo(
+    () => serializePlotConfig({
+      xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen,
+      counts: countsS.snapshot, rate: rateS.snapshot,
+    }),
+    [xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen, countsS.snapshot, rateS.snapshot],
+  );
+
+  // Keep the latest persist callback in a ref so the save effect does not re-run
+  // when the parent passes a new inline function each render.
+  const persistRef = useRef(onPersistConfig);
+  persistRef.current = onPersistConfig;
+
+  const lastSavedRef = useRef(null);
+  useEffect(() => {
+    const serialized = JSON.stringify(currentConfig);
+    if (lastSavedRef.current === null) { lastSavedRef.current = serialized; return; } // skip initial (hydration)
+    if (serialized === lastSavedRef.current) return;
+    if (!persistRef.current) { lastSavedRef.current = serialized; return; }
+    setSaveState('saving');
+    const t = setTimeout(() => {
+      Promise.resolve(persistRef.current(currentConfig))
+        .then(() => { lastSavedRef.current = serialized; setSaveState('saved'); })
+        .catch(() => setSaveState('error'));
+    }, 1000);
+    return () => clearTimeout(t);
+  }, [currentConfig]);
+```
+
+- [ ] **Step 6: Render the save-status hint in the global controls row**
+
+Find the global-controls row in `ExperimentAnalysisCharts` — the `<div className="flex items-center flex-wrap gap-3">` containing the `<h2>Cross-subject metrics</h2>`, the X-axis select, Color-by select, `TickStepControl`, and the `▸ Subjects` button. The Subjects button currently has `ml-auto` in its className. Replace that standalone button block:
+
+```jsx
+        {hasData && (
+          <button type="button" onClick={() => setSidebarOpen((o) => !o)}
+            className={[
+              'text-xs px-2 py-0.5 rounded border transition-colors ml-auto',
+              sidebarOpen
+                ? 'bg-gray-100 border-gray-300 text-gray-700'
+                : 'bg-white border-gray-200 text-gray-500 hover:text-gray-700 hover:border-gray-300',
+            ].join(' ')}>
+            {sidebarOpen ? '◂ Subjects' : '▸ Subjects'}
+          </button>
+        )}
+```
+
+with a wrapper that holds the status hint and the button (note `ml-auto` moved to the wrapper, removed from the button):
+
+```jsx
+        {hasData && (
+          <div className="ml-auto flex items-center gap-2">
+            {saveState === 'saving' && <span className="text-xs text-gray-400">Saving…</span>}
+            {saveState === 'saved'  && <span className="text-xs text-emerald-500">Saved ✓</span>}
+            {saveState === 'error'  && <span className="text-xs text-amber-500">Couldn't save layout</span>}
+            <button type="button" onClick={() => setSidebarOpen((o) => !o)}
+              className={[
+                'text-xs px-2 py-0.5 rounded border transition-colors',
+                sidebarOpen
+                  ? 'bg-gray-100 border-gray-300 text-gray-700'
+                  : 'bg-white border-gray-200 text-gray-500 hover:text-gray-700 hover:border-gray-300',
+              ].join(' ')}>
+              {sidebarOpen ? '◂ Subjects' : '▸ Subjects'}
+            </button>
+          </div>
+        )}
+```
+
+- [ ] **Step 7: Pass the new props from `ExperimentDetail.jsx`**
+
+In `frontend/src/pages/ExperimentDetail.jsx`, find the `<ExperimentAnalysisCharts ... />` usage (~line 365) and add the two props. It must use the page's existing `experiment` object and `id` (from `useParams`) and the already-imported `experimentsApi`:
+
+```jsx
+      <ExperimentAnalysisCharts
+        animals={animals}
+        experimentStatuses={experimentStatuses}
+        subjectTemplate={subjectTemplate}
+        dailyTemplate={dailyTemplate}
+        plotConfig={experiment.plot_config}
+        onPersistConfig={(cfg) => experimentsApi.savePlotConfig(id, cfg)}
+      />
+```
+
+(If `id` is not already in scope, use `experiment.id` instead. Verify which identifier the file uses before editing.)
+
+- [ ] **Step 8: Write the hydration + save tests**
+
+Append these two tests to `frontend/tests/ExperimentAnalysisCharts.test.jsx`. Note the file already mocks `recharts` and defines `ANIMALS`, `STATUSES`, `SUBJECT_TEMPLATE`, `DAILY_TEMPLATE`, and `renderChart()`. Add `act` to the testing-library import at the top of the file (change `import { render, screen, fireEvent } from '@testing-library/react';` to include `act`):
+
+```jsx
+import { render, screen, fireEvent, act } from '@testing-library/react';
+```
+
+Then append:
+
+```jsx
+it('hydrates hidden subjects and sidebar-open from plotConfig', () => {
+  render(
+    <ExperimentAnalysisCharts
+      animals={ANIMALS}
+      experimentStatuses={STATUSES}
+      subjectTemplate={SUBJECT_TEMPLATE}
+      dailyTemplate={DAILY_TEMPLATE}
+      plotConfig={{ hiddenSubjects: ['a1'], sidebarOpen: true }}
+    />,
+  );
+  // sidebar starts open (no click needed) and a1 starts hidden (unchecked)
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(false);
+  expect(screen.getByLabelText('Mouse-B1').checked).toBe(true);
+});
+
+describe('debounced auto-save', () => {
+  beforeEach(() => jest.useFakeTimers());
+  afterEach(() => jest.useRealTimers());
+
+  it('does not call onPersistConfig on initial render', () => {
+    const onPersist = jest.fn();
+    render(
+      <ExperimentAnalysisCharts
+        animals={ANIMALS} experimentStatuses={STATUSES}
+        subjectTemplate={SUBJECT_TEMPLATE} dailyTemplate={DAILY_TEMPLATE}
+        plotConfig={null} onPersistConfig={onPersist}
+      />,
+    );
+    act(() => { jest.advanceTimersByTime(1500); });
+    expect(onPersist).not.toHaveBeenCalled();
+  });
+
+  it('calls onPersistConfig ~1s after a change, with the updated config', () => {
+    const onPersist = jest.fn().mockResolvedValue({});
+    render(
+      <ExperimentAnalysisCharts
+        animals={ANIMALS} experimentStatuses={STATUSES}
+        subjectTemplate={SUBJECT_TEMPLATE} dailyTemplate={DAILY_TEMPLATE}
+        plotConfig={{ sidebarOpen: true }} onPersistConfig={onPersist}
+      />,
+    );
+    fireEvent.click(screen.getByLabelText('Mouse-A1')); // hide a1 → config change
+    expect(onPersist).not.toHaveBeenCalled();           // not yet (debounced)
+    act(() => { jest.advanceTimersByTime(1100); });
+    expect(onPersist).toHaveBeenCalledTimes(1);
+    expect(onPersist.mock.calls[0][0].hiddenSubjects).toContain('a1');
+  });
+});
+```
+
+- [ ] **Step 9: Run the chart test file to verify it passes**
+
+Run: `cd frontend && npx jest tests/ExperimentAnalysisCharts.test.jsx`
+Expected: PASS — the two original smoke tests plus the three new tests green. If a test reveals a genuine wiring problem, fix the wiring (do not weaken the test).
+
+- [ ] **Step 10: Run the full frontend suite (no new regressions)**
+
+Run: `cd frontend && npm test`
+Expected: PASS for all suites except the pre-existing `ExperimentCalendar` / `ExperimentDayView` failures (31 failures that also fail on `main` — unrelated). All other suites, including `crossSubjectChart`, `SubjectSidebar`, and `ExperimentAnalysisCharts`, green.
+
+- [ ] **Step 11: Build to confirm no compile errors**
+
+Run: `cd frontend && npm run build`
+Expected: Vite build succeeds with no errors.
+
+- [ ] **Step 12: Commit**
+
+```bash
+git add frontend/src/api/client.js frontend/src/components/AnalysisCharts.jsx frontend/src/pages/ExperimentDetail.jsx frontend/tests/ExperimentAnalysisCharts.test.jsx
+git commit -m "feat(frontend): hydrate + debounced-persist cross-subject plot config"
+```
+
+---
+
+## Manual Verification (after all tasks, requires DB migration applied)
+
+The running stack applies migrations on backend startup (`prisma migrate deploy` in the entrypoint). After `docker compose up --build`:
+
+- [ ] Open an experiment with animals + saved metrics. Change X-axis, toggle a few subjects off, open the sidebar, adjust a per-chart size. Observe a brief "Saving… → Saved ✓".
+- [ ] Reload the page → the same X-axis, hidden subjects, sidebar state, and chart size are restored.
+- [ ] Open a different experiment → it has its own independent settings (or defaults if never configured).
+- [ ] Confirm no new `audit_logs` rows are created by plot tweaks (only by template edits etc.).
+- [ ] Existing controls and the previously-shipped interactions (legend toggle/highlight, ordered tooltip) still work.
+
+## Self-Review Notes
+
+- **Spec coverage:** migration + nullable column (Task 1 Steps 3–4); `PUT /:id/plot-config` with validator, no audit log (Task 1 Steps 6–7, asserted in Step 1); read via existing `GET /:id` (no code needed — Prisma returns the column); API client method (Task 3 Step 1); `serializePlotConfig`/`readPlotConfig` with defensive defaults (Task 2); `useChartSettings` `initial`+`snapshot` refactor (Task 3 Step 2); hydrate-once + serialize + debounced save + status hint (Task 3 Steps 4–6); `ExperimentDetail` props (Task 3 Step 7); tests at all three layers (Task 1 Step 1, Task 2 Step 1, Task 3 Step 8); manual checks. All spec sections covered.
+- **No-audit-log requirement:** explicitly asserted by `expect(prisma.auditLog.create).not.toHaveBeenCalled()` (Task 1 Step 1).
+- **Save-on-load loop prevention:** `lastSavedRef` initial-null skip (Task 3 Step 5) + the "does not call onPersistConfig on initial render" test (Task 3 Step 8).
+- **Naming consistency:** `plot_config` (DB/route), `plotConfig`/`onPersistConfig` (props), `serializePlotConfig`/`readPlotConfig` (helpers), `snapshot` (hook) used identically across tasks.
+- **No disallowed changes:** `SubjectAnalysisCharts` calls `useChartSettings(defaultHeight)` with no `initial`, which defaults to `{}` → unchanged behavior; template/subject-template routes untouched.

docs/superpowers/plans/2026-07-06-experiment-data-export.md

@@ -0,0 +1,705 @@
+# Experiment Data Export (CSV) Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Add a client-side CSV export on the experiment page that produces a date×subject matrix for any chosen daily parameter (including session metrics).
+
+**Architecture:** A pure, unit-tested helper module (`frontend/src/lib/dataExport.js`) enumerates exportable parameters, pivots fetched daily statuses into a date-row × subject-column matrix, and serializes to CSV. A modal component (`ExportDataModal.jsx`) fetches the full daily-statuses set on open, drives the picker, and triggers a browser download. `ExperimentDetail.jsx` gets an "Export data" button. No backend changes — the existing `GET /:id/daily-statuses` endpoint already returns every field needed.
+
+**Tech Stack:** React 18, Jest + @testing-library, existing `experimentsApi` axios client, existing `Modal`/`Button` UI components.
+
+---
+
+## Reference: data shapes (read before starting)
+
+**Daily template field** (`dailyTemplate` array items):
+```js
+{ fieldId: '0000…0002', key: 'vitals', label: 'Vitals', type: 'text', builtin: true, active: true, tags: [] }
+```
+- `builtin: true`  → value stored at `status[field.key]` (e.g. `status.vitals`).
+- `builtin: false` → value stored at `status.custom_fields[field.fieldId]`.
+
+**Daily status** (from `experimentsApi.getDailyStatuses(id, {})`):
+```js
+{
+  id, animal_id, date: '2026-07-01T00:00:00.000Z',
+  experiment_description, vitals, treatment, notes,   // builtin columns
+  custom_fields: { '<fieldId>': value, … } | null,
+  analysis_summary: { total: 12, success_rate: 0.83, counts: { Success: 10, Failure: 2 } } | null,
+}
+```
+
+**Animal**: `{ id, animal_name, animal_id_string, subject_info, … }`.
+
+**Parameter descriptor** (produced by `listExportableParams`, consumed everywhere):
+```js
+{ id, label, group: 'metrics' | 'daily', kind: 'total'|'success_rate'|'category'|'builtin'|'custom',
+  category?, statusKey?, fieldId? }
+```
+
+---
+
+## Task 1: `extractValue` — read one parameter's value from a status
+
+**Files:**
+- Create: `frontend/src/lib/dataExport.js`
+- Test: `frontend/tests/dataExport.test.js`
+
+- [ ] **Step 1: Write the failing test**
+
+Create `frontend/tests/dataExport.test.js`:
+```js
+import { extractValue } from '../src/lib/dataExport';
+
+const status = {
+  vitals: 'ok',
+  custom_fields: { 'f-weight': 250 },
+  analysis_summary: { total: 12, success_rate: 0.83, counts: { Success: 10, Failure: 2 } },
+};
+
+describe('extractValue', () => {
+  it('reads a builtin field via statusKey', () => {
+    expect(extractValue(status, { kind: 'builtin', statusKey: 'vitals' })).toBe('ok');
+  });
+  it('reads a custom field via fieldId', () => {
+    expect(extractValue(status, { kind: 'custom', fieldId: 'f-weight' })).toBe(250);
+  });
+  it('reads session-metric total', () => {
+    expect(extractValue(status, { kind: 'total' })).toBe(12);
+  });
+  it('reads session-metric success_rate as a raw 0-1 fraction', () => {
+    expect(extractValue(status, { kind: 'success_rate' })).toBe(0.83);
+  });
+  it('reads a dynamic count category', () => {
+    expect(extractValue(status, { kind: 'category', category: 'Failure' })).toBe(2);
+  });
+  it('returns null when analysis_summary is absent', () => {
+    expect(extractValue({ custom_fields: {} }, { kind: 'total' })).toBeNull();
+    expect(extractValue({}, { kind: 'category', category: 'Success' })).toBeNull();
+  });
+  it('returns null for a missing custom field', () => {
+    expect(extractValue({ custom_fields: {} }, { kind: 'custom', fieldId: 'nope' })).toBeNull();
+    expect(extractValue({}, { kind: 'builtin', statusKey: 'notes' })).toBeNull();
+  });
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t extractValue`
+Expected: FAIL — "extractValue is not a function" / cannot import.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Create `frontend/src/lib/dataExport.js`:
+```js
+// Pure helpers for exporting daily-parameter data as a date×subject CSV matrix.
+// No React, no I/O — mirrors the crossSubjectChart.js pure-helper pattern.
+
+// Read a single parameter's raw value from one daily status.
+// Returns null when the value is absent. Note: 0 and '' are returned as-is
+// (real values); only genuinely-missing lookups become null.
+export function extractValue(status, param) {
+  if (!status || !param) return null;
+  switch (param.kind) {
+    case 'total':
+      return status.analysis_summary?.total ?? null;
+    case 'success_rate':
+      return status.analysis_summary?.success_rate ?? null;
+    case 'category':
+      return status.analysis_summary?.counts?.[param.category] ?? null;
+    case 'builtin':
+      return status[param.statusKey] ?? null;
+    case 'custom':
+      return status.custom_fields?.[param.fieldId] ?? null;
+    default:
+      return null;
+  }
+}
+```
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t extractValue`
+Expected: PASS (7 assertions).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(frontend): extractValue helper for data export"
+```
+
+---
+
+## Task 2: `listExportableParams` — enumerate the picker options
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js`
+- Test: `frontend/tests/dataExport.test.js`
+
+- [ ] **Step 1: Write the failing test**
+
+Append to `frontend/tests/dataExport.test.js`:
+```js
+import { listExportableParams } from '../src/lib/dataExport';
+
+const dailyTemplate = [
+  { fieldId: 'b-vitals', key: 'vitals', label: 'Vitals', builtin: true, active: true },
+  { fieldId: 'c-weight', key: 'weight', label: 'Weight (g)', builtin: false, active: false },
+];
+const statuses = [
+  { analysis_summary: { counts: { Success: 1, Failure: 0 } } },
+  { analysis_summary: { counts: { Success: 2, Other: 1 } } },
+  { analysis_summary: null },
+];
+
+describe('listExportableParams', () => {
+  const params = listExportableParams(dailyTemplate, statuses);
+  it('starts with the two fixed session metrics', () => {
+    expect(params.slice(0, 2)).toEqual([
+      expect.objectContaining({ id: '__total__', label: 'Total attempts', group: 'metrics', kind: 'total' }),
+      expect.objectContaining({ id: '__success_rate__', label: 'Success rate', group: 'metrics', kind: 'success_rate' }),
+    ]);
+  });
+  it('adds one metrics entry per dynamic count category, sorted', () => {
+    const cats = params.filter((p) => p.kind === 'category').map((p) => p.label);
+    expect(cats).toEqual(['Failure', 'Other', 'Success']);
+  });
+  it('includes every template field (incl. inactive) in the daily group', () => {
+    const daily = params.filter((p) => p.group === 'daily');
+    expect(daily).toEqual([
+      expect.objectContaining({ label: 'Vitals', kind: 'builtin', statusKey: 'vitals' }),
+      expect.objectContaining({ label: 'Weight (g)', kind: 'custom', fieldId: 'c-weight' }),
+    ]);
+  });
+  it('gives every param a unique id', () => {
+    const ids = params.map((p) => p.id);
+    expect(new Set(ids).size).toBe(ids.length);
+  });
+  it('tolerates empty/missing inputs', () => {
+    expect(listExportableParams(undefined, undefined).length).toBe(2); // just the two fixed metrics
+  });
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t listExportableParams`
+Expected: FAIL — "listExportableParams is not a function".
+
+- [ ] **Step 3: Write minimal implementation**
+
+Append to `frontend/src/lib/dataExport.js`:
+```js
+// Build the grouped, ordered list of exportable parameters.
+// Session metrics (total, success_rate, then each dynamic count category found
+// in the data) come first; then every field defined in the daily template,
+// including inactive ones (historical data may exist).
+export function listExportableParams(dailyTemplate, statuses) {
+  const params = [
+    { id: '__total__', label: 'Total attempts', group: 'metrics', kind: 'total' },
+    { id: '__success_rate__', label: 'Success rate', group: 'metrics', kind: 'success_rate' },
+  ];
+
+  const cats = new Set();
+  for (const s of statuses ?? []) {
+    const counts = s?.analysis_summary?.counts;
+    if (counts && typeof counts === 'object') {
+      for (const k of Object.keys(counts)) cats.add(k);
+    }
+  }
+  for (const cat of [...cats].sort()) {
+    params.push({ id: `__cat__${cat}`, label: cat, group: 'metrics', kind: 'category', category: cat });
+  }
+
+  for (const f of dailyTemplate ?? []) {
+    if (f.builtin) {
+      params.push({ id: `b:${f.fieldId}`, label: f.label, group: 'daily', kind: 'builtin', statusKey: f.key });
+    } else {
+      params.push({ id: `c:${f.fieldId}`, label: f.label, group: 'daily', kind: 'custom', fieldId: f.fieldId });
+    }
+  }
+
+  return params;
+}
+```
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t listExportableParams`
+Expected: PASS.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(frontend): listExportableParams enumerates export options"
+```
+
+---
+
+## Task 3: `buildMatrix` — pivot statuses into date rows × subject columns
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js`
+- Test: `frontend/tests/dataExport.test.js`
+
+- [ ] **Step 1: Write the failing test**
+
+Append to `frontend/tests/dataExport.test.js`:
+```js
+import { buildMatrix } from '../src/lib/dataExport';
+
+const animals = [
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002' },
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001' },
+];
+const totalParam = { kind: 'total' };
+
+describe('buildMatrix', () => {
+  it('orders columns by animal_name and rows by date ascending', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-02T00:00:00.000Z', analysis_summary: { total: 5 } },
+      { animal_id: 'a2', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 9 } },
+    ];
+    const m = buildMatrix(statuses, animals, totalParam);
+    expect(m.columns.map((c) => c.header)).toEqual(['Alpha', 'Beta']);
+    expect(m.rows.map((r) => r.date)).toEqual(['2026-07-01', '2026-07-02']);
+    // Row for 07-01: Alpha blank, Beta 9
+    expect(m.rows[0].values).toEqual(['', 9]);
+    // Row for 07-02: Alpha 5, Beta blank
+    expect(m.rows[1].values).toEqual([5, '']);
+  });
+  it('includes only dates that have at least one value (0 counts as a value)', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 0 } },
+      { animal_id: 'a1', date: '2026-07-03T00:00:00.000Z', analysis_summary: null }, // no value
+    ];
+    const m = buildMatrix(statuses, animals, totalParam);
+    expect(m.rows.map((r) => r.date)).toEqual(['2026-07-01']);
+    expect(m.rows[0].values).toEqual([0, '']);
+  });
+  it('disambiguates duplicate animal names with the id string', () => {
+    const dupAnimals = [
+      { id: 'a1', animal_name: 'Rat', animal_id_string: 'R-001' },
+      { id: 'a2', animal_name: 'Rat', animal_id_string: 'R-002' },
+    ];
+    const statuses = [{ animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 1 } }];
+    const m = buildMatrix(statuses, dupAnimals, totalParam);
+    expect(m.columns.map((c) => c.header)).toEqual(['Rat (R-001)', 'Rat (R-002)']);
+  });
+  it('keeps the first status when a subject has duplicates on one date', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 7 } },
+      { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 99 } },
+    ];
+    const m = buildMatrix(statuses, animals, totalParam);
+    expect(m.rows[0].values).toEqual([7, '']);
+  });
+  it('returns empty rows when no status has a value', () => {
+    const m = buildMatrix([{ animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: null }], animals, totalParam);
+    expect(m.rows).toEqual([]);
+    expect(m.columns.length).toBe(2);
+  });
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t buildMatrix`
+Expected: FAIL — "buildMatrix is not a function".
+
+- [ ] **Step 3: Write minimal implementation**
+
+Append to `frontend/src/lib/dataExport.js`:
+```js
+// A cell has a value unless it is null, undefined, or the empty string.
+// (0 and false are real values.)
+function hasValue(v) {
+  return v !== null && v !== undefined && v !== '';
+}
+
+function dateKey(date) {
+  return String(date).slice(0, 10); // ISO datetime or date → YYYY-MM-DD
+}
+
+// Pivot statuses into { columns, rows }.
+//   columns: [{ id, header }] — all animals, ordered by name, headers
+//            disambiguated with animal_id_string on duplicate names.
+//   rows:    [{ date, values }] — one per date that has ≥1 value; values are
+//            aligned to columns, blank cells are '' (empty string).
+export function buildMatrix(statuses, animals, param) {
+  const sortedAnimals = [...(animals ?? [])].sort((a, b) =>
+    String(a.animal_name ?? '').localeCompare(String(b.animal_name ?? '')),
+  );
+
+  const nameCounts = new Map();
+  for (const a of sortedAnimals) {
+    const n = a.animal_name ?? '';
+    nameCounts.set(n, (nameCounts.get(n) ?? 0) + 1);
+  }
+  const columns = sortedAnimals.map((a) => {
+    const name = a.animal_name ?? '';
+    const header = nameCounts.get(name) > 1 ? `${name} (${a.animal_id_string ?? ''})` : name;
+    return { id: a.id, header };
+  });
+  const colIndex = new Map(columns.map((c, i) => [c.id, i]));
+
+  // cells: dateKey -> Map(animalId -> value); first status per (date, animal) wins.
+  const cells = new Map();
+  const datesWithData = new Set();
+  const ordered = [...(statuses ?? [])].sort((a, b) => dateKey(a.date).localeCompare(dateKey(b.date)));
+  for (const s of ordered) {
+    if (!colIndex.has(s.animal_id)) continue;
+    const dk = dateKey(s.date);
+    if (!cells.has(dk)) cells.set(dk, new Map());
+    const byAnimal = cells.get(dk);
+    if (byAnimal.has(s.animal_id)) continue; // first wins
+    const v = extractValue(s, param);
+    byAnimal.set(s.animal_id, v);
+    if (hasValue(v)) datesWithData.add(dk);
+  }
+
+  const rows = [...datesWithData].sort().map((dk) => {
+    const byAnimal = cells.get(dk);
+    const values = columns.map((c) => {
+      const v = byAnimal.has(c.id) ? byAnimal.get(c.id) : null;
+      return hasValue(v) ? v : '';
+    });
+    return { date: dk, values };
+  });
+
+  return { columns, rows };
+}
+```
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t buildMatrix`
+Expected: PASS.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(frontend): buildMatrix pivots statuses into date×subject grid"
+```
+
+---
+
+## Task 4: `toCSV` + `csvFilename` — serialize and name the file
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js`
+- Test: `frontend/tests/dataExport.test.js`
+
+- [ ] **Step 1: Write the failing test**
+
+Append to `frontend/tests/dataExport.test.js`:
+```js
+import { toCSV, csvFilename } from '../src/lib/dataExport';
+
+describe('toCSV', () => {
+  it('writes a header row of Date + column headers, then data rows', () => {
+    const matrix = {
+      columns: [{ id: 'a1', header: 'Alpha' }, { id: 'a2', header: 'Beta' }],
+      rows: [{ date: '2026-07-01', values: [5, ''] }, { date: '2026-07-02', values: ['', 9] }],
+    };
+    expect(toCSV(matrix)).toBe('Date,Alpha,Beta\n2026-07-01,5,\n2026-07-02,,9');
+  });
+  it('escapes commas, quotes, and newlines per RFC 4180', () => {
+    const matrix = {
+      columns: [{ id: 'a1', header: 'Note, field' }],
+      rows: [{ date: '2026-07-01', values: ['he said "hi"'] }, { date: '2026-07-02', values: ['line1\nline2'] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Date,"Note, field"\n2026-07-01,"he said ""hi"""\n2026-07-02,"line1\nline2"',
+    );
+  });
+});
+
+describe('csvFilename', () => {
+  it('slugifies the experiment title and parameter label', () => {
+    expect(csvFilename('My Study #1', 'Success rate')).toBe('My-Study-1-Success-rate.csv');
+  });
+  it('falls back to "export" when both slugs are empty', () => {
+    expect(csvFilename('', '')).toBe('export.csv');
+  });
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js -t "toCSV|csvFilename"`
+Expected: FAIL — "toCSV is not a function".
+
+- [ ] **Step 3: Write minimal implementation**
+
+Append to `frontend/src/lib/dataExport.js`:
+```js
+function escapeCsvCell(value) {
+  const s = value === null || value === undefined ? '' : String(value);
+  return /[",\n]/.test(s) ? `"${s.replace(/"/g, '""')}"` : s;
+}
+
+// Serialize a matrix to an RFC-4180-ish CSV string (LF line endings).
+// First column is the date; remaining columns follow matrix.columns order.
+export function toCSV(matrix) {
+  const header = ['Date', ...matrix.columns.map((c) => c.header)].map(escapeCsvCell).join(',');
+  const lines = matrix.rows.map((r) => [r.date, ...r.values].map(escapeCsvCell).join(','));
+  return [header, ...lines].join('\n');
+}
+
+// Build a download filename from the experiment title and parameter label.
+export function csvFilename(title, label) {
+  const slug = (s) => String(s ?? '').replace(/[^a-z0-9]+/gi, '-').replace(/^-+|-+$/g, '');
+  const base = [slug(title), slug(label)].filter(Boolean).join('-');
+  return `${base || 'export'}.csv`;
+}
+```
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `cd frontend && npx jest tests/dataExport.test.js`
+Expected: PASS (all describe blocks in the file).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(frontend): toCSV + csvFilename for data export"
+```
+
+---
+
+## Task 5: `ExportDataModal` component
+
+**Files:**
+- Create: `frontend/src/components/ExportDataModal.jsx`
+
+This component is rendered as the *content* of the shared `Modal` (same pattern as `AnimalForm`/`TemplateEditor`), so it mounts only when the modal opens — the fetch runs on mount.
+
+- [ ] **Step 1: Create the component**
+
+Create `frontend/src/components/ExportDataModal.jsx`:
+```jsx
+import React, { useEffect, useMemo, useState } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+import { listExportableParams, buildMatrix, toCSV, csvFilename } from '../lib/dataExport';
+
+const GROUP_LABELS = { metrics: 'Session metrics', daily: 'Daily record fields' };
+
+function triggerDownload(filename, text) {
+  const blob = new Blob([text], { type: 'text/csv;charset=utf-8;' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = filename;
+  document.body.appendChild(a);
+  a.click();
+  document.body.removeChild(a);
+  URL.revokeObjectURL(url);
+}
+
+export default function ExportDataModal({ experimentTitle, experimentId, dailyTemplate, animals, onClose }) {
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [statuses, setStatuses] = useState([]);
+  const [selectedId, setSelectedId] = useState(null);
+
+  useEffect(() => {
+    let alive = true;
+    setLoading(true);
+    setError(null);
+    experimentsApi.getDailyStatuses(experimentId, {})
+      .then((data) => { if (alive) setStatuses(data); })
+      .catch((err) => { if (alive) setError(err.message); })
+      .finally(() => { if (alive) setLoading(false); });
+    return () => { alive = false; };
+  }, [experimentId]);
+
+  const params = useMemo(() => listExportableParams(dailyTemplate, statuses), [dailyTemplate, statuses]);
+
+  // Default the selection to the first parameter once params are available.
+  useEffect(() => {
+    if (selectedId === null && params.length > 0) setSelectedId(params[0].id);
+  }, [params, selectedId]);
+
+  const selectedParam = params.find((p) => p.id === selectedId) ?? null;
+
+  const matrix = useMemo(
+    () => (selectedParam ? buildMatrix(statuses, animals, selectedParam) : { columns: [], rows: [] }),
+    [statuses, animals, selectedParam],
+  );
+
+  const hasData = matrix.rows.length > 0;
+
+  // Group params for <optgroup> rendering, preserving order.
+  const grouped = useMemo(() => {
+    const out = [];
+    for (const p of params) {
+      let g = out.find((x) => x.group === p.group);
+      if (!g) { g = { group: p.group, items: [] }; out.push(g); }
+      g.items.push(p);
+    }
+    return out;
+  }, [params]);
+
+  function handleExport() {
+    if (!hasData || !selectedParam) return;
+    triggerDownload(csvFilename(experimentTitle, selectedParam.label), toCSV(matrix));
+    onClose();
+  }
+
+  if (loading) return <p className="text-sm text-gray-400" aria-live="polite">Loading data…</p>;
+  if (error) return <Alert type="error" message={error} />;
+
+  return (
+    <div className="space-y-4">
+      <p className="text-sm text-gray-500">
+        Export one parameter as a CSV file — each row is a date, each column is a subject.
+      </p>
+
+      <div>
+        <label htmlFor="export-param" className="block text-xs font-medium text-gray-500 mb-1">Parameter</label>
+        <select
+          id="export-param"
+          value={selectedId ?? ''}
+          onChange={(e) => setSelectedId(e.target.value)}
+          className="w-full border border-gray-200 rounded px-2 py-1.5 text-sm bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400"
+        >
+          {grouped.map((g) => (
+            <optgroup key={g.group} label={GROUP_LABELS[g.group] ?? g.group}>
+              {g.items.map((p) => <option key={p.id} value={p.id}>{p.label}</option>)}
+            </optgroup>
+          ))}
+        </select>
+      </div>
+
+      <p className="text-xs text-gray-400">
+        {hasData
+          ? `${matrix.rows.length} date${matrix.rows.length !== 1 ? 's' : ''} × ${matrix.columns.length} subject${matrix.columns.length !== 1 ? 's' : ''}`
+          : 'No data for this parameter yet.'}
+      </p>
+
+      <div className="flex justify-end gap-2 pt-2">
+        <Button variant="secondary" onClick={onClose}>Cancel</Button>
+        <Button onClick={handleExport} disabled={!hasData}>Export CSV</Button>
+      </div>
+    </div>
+  );
+}
+```
+
+- [ ] **Step 2: Verify it compiles (build)**
+
+Run: `cd frontend && npx vite build`
+Expected: build succeeds with no import/JSX errors. (There is no `ExportDataModal` test — its logic lives in the unit-tested `dataExport.js`; the DOM download path is verified manually in Task 7.)
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add frontend/src/components/ExportDataModal.jsx
+git commit -m "feat(frontend): ExportDataModal — pick a parameter and download CSV"
+```
+
+---
+
+## Task 6: Wire the "Export data" button into the experiment page
+
+**Files:**
+- Modify: `frontend/src/pages/ExperimentDetail.jsx`
+
+- [ ] **Step 1: Import the modal**
+
+In `frontend/src/pages/ExperimentDetail.jsx`, add to the imports near the other component imports (after the `ExperimentCalendar` import on line 11):
+```jsx
+import ExportDataModal from '../components/ExportDataModal';
+```
+
+- [ ] **Step 2: Add modal open/close state**
+
+Immediately after the `const [showSubjectTemplate, setShowSubjectTemplate] = useState(false);` line (around line 64), add:
+```jsx
+  const [showExport, setShowExport] = useState(false);
+```
+
+- [ ] **Step 3: Add the header button**
+
+In the header actions area, replace the single Add-Animal button block:
+```jsx
+        <Button onClick={() => setShowAddAnimal(true)}>+ Add Animal</Button>
+```
+with:
+```jsx
+        <div className="flex gap-2">
+          <Button variant="secondary" onClick={() => setShowExport(true)}>Export data</Button>
+          <Button onClick={() => setShowAddAnimal(true)}>+ Add Animal</Button>
+        </div>
+```
+
+- [ ] **Step 4: Render the modal**
+
+Just before the closing `</div>` and the final Edit-Animal `Modal` (after the `Edit Animal` modal block, around line 406), add:
+```jsx
+      <Modal isOpen={showExport} onClose={() => setShowExport(false)} title="Export data" size="md">
+        <ExportDataModal
+          experimentId={id}
+          experimentTitle={experiment.title}
+          dailyTemplate={dailyTemplate}
+          animals={animals}
+          onClose={() => setShowExport(false)}
+        />
+      </Modal>
+```
+
+- [ ] **Step 5: Build to verify wiring**
+
+Run: `cd frontend && npx vite build`
+Expected: build succeeds.
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add frontend/src/pages/ExperimentDetail.jsx
+git commit -m "feat(frontend): Export data button + modal on experiment page"
+```
+
+---
+
+## Task 7: Full-suite verification & manual smoke test
+
+**Files:** none (verification only)
+
+- [ ] **Step 1: Run the whole frontend unit suite**
+
+Run: `cd frontend && npm test`
+Expected: all suites PASS, including `tests/dataExport.test.js`.
+
+- [ ] **Step 2: Manual smoke test**
+
+Bring up the dev stack (`docker-compose -f docker-compose.dev.yml up` or the project's usual dev command), open an experiment that has animals and some daily statuses, then:
+- Click **Export data** → modal opens, parameter dropdown shows a **Session metrics** group (Total attempts, Success rate, any count categories) and a **Daily record fields** group (all template fields).
+- The summary line shows a plausible "N dates × M subjects".
+- Pick a session metric and a daily field; confirm the summary updates and **Export CSV** downloads a file.
+- Open the CSV: first column `Date` (YYYY-MM-DD rows ascending), one column per subject (by name), correct values, blank cells where a subject had no value, and **success rate as a raw 0–1 fraction**.
+- Pick a parameter with no data → summary reads "No data for this parameter yet." and **Export CSV** is disabled.
+
+- [ ] **Step 3: Final commit (if any manual fixes were needed)**
+
+```bash
+git add -A
+git commit -m "chore(frontend): finalize experiment data export"
+```
+
+---
+
+## Self-review notes (for the implementer)
+
+- The whole feature is client-side; **no backend files change**. If a test asks you to touch `backend/`, stop — the plan is wrong.
+- `success_rate` is exported **raw (0–1)**, deliberately not multiplied to a percentage.
+- All daily template fields are exportable, **including inactive ones** — this is intentional (historical data).
+- Parameter descriptor property names (`kind`, `statusKey`, `fieldId`, `category`, `group`, `id`, `label`) must stay identical across `listExportableParams`, `extractValue`, `buildMatrix`, and `ExportDataModal`.

docs/superpowers/plans/2026-07-19-configurable-data-export.md

@@ -0,0 +1,926 @@
+# Configurable Data Export Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Let the export modal assign any of Date/Subject/Parameter to rows and columns, pin the third dimension (shown as a top context line), and emit each subject's group in a separate cell when Subject is an axis.
+
+**Architecture:** Generalize the pure helpers in `frontend/src/lib/dataExport.js` around three interchangeable dimensions (date, subject, parameter). Each dimension produces an ordered list of "members"; `buildMatrix` resolves every cell's `(dateKey, animalId, param)` triple through a status index. `ExportDataModal.jsx` becomes glue over these helpers with four controls. `ExperimentDetail.jsx` passes two new props.
+
+**Tech Stack:** React 18, plain ES modules, Jest + `@testing-library/react` (jsdom). No new dependencies.
+
+**Spec:** `docs/superpowers/specs/2026-07-19-configurable-data-export-design.md`
+
+## Global Constraints
+
+- `dataExport.js` stays pure: no React, no I/O (mirrors `crossSubjectChart.js`).
+- Cell value semantics: `0` and `''` are **real** values; only genuinely-missing lookups render as blank (`''`). Use the existing `hasValue` helper.
+- CSV: LF (`\n`) line endings; escape every cell via the existing `escapeCsvCell`.
+- Empty-member rule: **Subject members are always kept**; **Date and Parameter members are dropped when entirely blank** in the grid.
+- Group field ids: `__none__` (None), `__name__` (Name), `__id__` (Subject ID), otherwise a `subject_info` field id. Missing group value renders as `—`.
+- Default modal state must reproduce today's export exactly: Rows = Date, Columns = Subject, Fixed = Parameter (first parameter).
+- Context line is **beginning only** (no footer); two cells: pinned dimension label, pinned value.
+- Run tests from `frontend/`. Single file: `npx jest tests/dataExport.test.js`. Component file: `npx jest tests/ExportDataModal.test.jsx`.
+
+---
+
+### Task 1: Dimension primitives + date members + status index
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (add exports; keep existing `extractValue`, `listExportableParams`, `hasValue`, `dateKey`, `escapeCsvCell`, `csvFilename`)
+- Test: `frontend/tests/dataExport.test.js`
+
+**Interfaces:**
+- Consumes: existing `dateKey(date)` (private), `hasValue(v)` (private) in `dataExport.js`.
+- Produces:
+  - `EXPORT_DIMENSIONS: Array<{ dim: 'date'|'subject'|'parameter', label: string }>`
+  - `dimLabel(dim: string): string`
+  - `otherDimension(rowDim: string, colDim: string): string` — the leftover dimension
+  - `subjectGroupValue(animal: object, groupField: string): string|null` — `null` when `groupField` is falsy/`__none__`; `—` when the value is missing/empty
+  - `listDateMembers(statuses: array): Array<{ id, label, dateKey }>` — sorted unique dateKeys
+  - `buildStatusIndex(statuses: array): Map<string, Map<any, status>>` — `dateKey → animalId → status`, first-wins
+
+- [ ] **Step 1: Write the failing tests**
+
+Append to `frontend/tests/dataExport.test.js`:
+
+```js
+import {
+  EXPORT_DIMENSIONS, dimLabel, otherDimension, subjectGroupValue,
+  listDateMembers, buildStatusIndex,
+} from '../src/lib/dataExport';
+
+describe('dimension primitives', () => {
+  it('exposes the three dimensions with labels', () => {
+    expect(EXPORT_DIMENSIONS.map((d) => d.dim)).toEqual(['date', 'subject', 'parameter']);
+    expect(dimLabel('date')).toBe('Date');
+    expect(dimLabel('subject')).toBe('Subject');
+    expect(dimLabel('parameter')).toBe('Parameter');
+  });
+  it('otherDimension returns the leftover', () => {
+    expect(otherDimension('date', 'subject')).toBe('parameter');
+    expect(otherDimension('parameter', 'date')).toBe('subject');
+  });
+});
+
+describe('subjectGroupValue', () => {
+  const animal = { animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { sex: 'M', cohort: '' } };
+  it('returns null when no group field', () => {
+    expect(subjectGroupValue(animal, '__none__')).toBeNull();
+    expect(subjectGroupValue(animal, '')).toBeNull();
+  });
+  it('resolves name / id / subject_info fields', () => {
+    expect(subjectGroupValue(animal, '__name__')).toBe('Alpha');
+    expect(subjectGroupValue(animal, '__id__')).toBe('R-001');
+    expect(subjectGroupValue(animal, 'sex')).toBe('M');
+  });
+  it('renders missing or empty values as an em dash', () => {
+    expect(subjectGroupValue(animal, 'cohort')).toBe('—');
+    expect(subjectGroupValue({}, 'sex')).toBe('—');
+  });
+});
+
+describe('listDateMembers', () => {
+  it('returns sorted unique dateKeys with id/label', () => {
+    const statuses = [
+      { date: '2026-07-02T00:00:00.000Z' },
+      { date: '2026-07-01T12:00:00.000Z' },
+      { date: '2026-07-02T09:00:00.000Z' },
+    ];
+    expect(listDateMembers(statuses)).toEqual([
+      { id: '2026-07-01', label: '2026-07-01', dateKey: '2026-07-01' },
+      { id: '2026-07-02', label: '2026-07-02', dateKey: '2026-07-02' },
+    ]);
+  });
+  it('tolerates empty input', () => {
+    expect(listDateMembers(undefined)).toEqual([]);
+  });
+});
+
+describe('buildStatusIndex', () => {
+  it('indexes by dateKey then animalId, first status wins', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 7 } },
+      { animal_id: 'a1', date: '2026-07-01T06:00:00.000Z', analysis_summary: { total: 99 } },
+      { animal_id: 'a2', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 3 } },
+    ];
+    const idx = buildStatusIndex(statuses);
+    expect(idx.get('2026-07-01').get('a1').analysis_summary.total).toBe(7);
+    expect(idx.get('2026-07-01').get('a2').analysis_summary.total).toBe(3);
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "dimension primitives"`
+Expected: FAIL — `EXPORT_DIMENSIONS is not defined` / imports undefined.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Add to `frontend/src/lib/dataExport.js` (after the existing `listExportableParams`, before `hasValue`):
+
+```js
+export const EXPORT_DIMENSIONS = [
+  { dim: 'date', label: 'Date' },
+  { dim: 'subject', label: 'Subject' },
+  { dim: 'parameter', label: 'Parameter' },
+];
+
+export function dimLabel(dim) {
+  return EXPORT_DIMENSIONS.find((d) => d.dim === dim)?.label ?? '';
+}
+
+export function otherDimension(rowDim, colDim) {
+  return EXPORT_DIMENSIONS.map((d) => d.dim).find((d) => d !== rowDim && d !== colDim) ?? null;
+}
+
+// Resolve a subject's group value for a given group field id.
+// null  -> no grouping (field is falsy or '__none__')
+// '—'   -> grouping is on but this subject has no value
+export function subjectGroupValue(animal, groupField) {
+  if (!groupField || groupField === '__none__') return null;
+  if (groupField === '__name__') return animal?.animal_name ?? '—';
+  if (groupField === '__id__') return animal?.animal_id_string ?? '—';
+  const v = animal?.subject_info?.[groupField];
+  return v === null || v === undefined || v === '' ? '—' : v;
+}
+
+export function listDateMembers(statuses) {
+  const keys = new Set();
+  for (const s of statuses ?? []) {
+    if (s?.date) keys.add(dateKey(s.date));
+  }
+  return [...keys].sort().map((k) => ({ id: k, label: k, dateKey: k }));
+}
+
+// dateKey -> Map(animalId -> status); first status per (date, animal) wins,
+// scanning in date order (matches the legacy buildMatrix tie-break).
+export function buildStatusIndex(statuses) {
+  const index = new Map();
+  const ordered = [...(statuses ?? [])].sort((a, b) => dateKey(a?.date).localeCompare(dateKey(b?.date)));
+  for (const s of ordered) {
+    if (!s?.date || s.animal_id === null || s.animal_id === undefined) continue;
+    const dk = dateKey(s.date);
+    if (!index.has(dk)) index.set(dk, new Map());
+    const byAnimal = index.get(dk);
+    if (!byAnimal.has(s.animal_id)) byAnimal.set(s.animal_id, s);
+  }
+  return index;
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS (new suites green, all pre-existing suites still green).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): dimension primitives, date members, status index"
+```
+
+---
+
+### Task 2: Subject + parameter members, dimension dispatcher
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js`
+- Test: `frontend/tests/dataExport.test.js`
+
+**Interfaces:**
+- Consumes: `subjectGroupValue`, `listDateMembers`, `listExportableParams` (existing).
+- Produces:
+  - `listSubjectMembers(animals, groupField): Array<{ id, label, animalId, group }>` — headers disambiguated by `animal_id_string` on duplicate names; clustered by group value then sorted by name/header when grouping is on, else name/header only.
+  - `listParameterMembers(dailyTemplate, statuses): Array<{ id, label, param, group }>` — wraps `listExportableParams`.
+  - `listDimensionMembers(dim, { statuses, animals, dailyTemplate, groupField }): Array<member>`
+
+- [ ] **Step 1: Write the failing tests**
+
+Append to `frontend/tests/dataExport.test.js`:
+
+```js
+import { listSubjectMembers, listParameterMembers, listDimensionMembers } from '../src/lib/dataExport';
+
+describe('listSubjectMembers', () => {
+  const animals = [
+    { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+    { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+    { id: 'a3', animal_name: 'Gamma', animal_id_string: 'R-003', subject_info: { grp: 'Control' } },
+  ];
+  it('orders by name and carries group=null when no group field', () => {
+    const m = listSubjectMembers(animals, '__none__');
+    expect(m.map((s) => s.label)).toEqual(['Alpha', 'Beta', 'Gamma']);
+    expect(m.every((s) => s.group === null)).toBe(true);
+    expect(m[0]).toMatchObject({ id: 'a1', animalId: 'a1' });
+  });
+  it('clusters by group value then name when grouping is on', () => {
+    const m = listSubjectMembers(animals, 'grp');
+    expect(m.map((s) => [s.group, s.label])).toEqual([
+      ['Control', 'Alpha'], ['Control', 'Gamma'], ['Drug', 'Beta'],
+    ]);
+  });
+  it('disambiguates duplicate names with the id string', () => {
+    const dup = [
+      { id: 'a1', animal_name: 'Rat', animal_id_string: 'R-001' },
+      { id: 'a2', animal_name: 'Rat', animal_id_string: 'R-002' },
+    ];
+    expect(listSubjectMembers(dup, '__none__').map((s) => s.label)).toEqual(['Rat (R-001)', 'Rat (R-002)']);
+  });
+});
+
+describe('listParameterMembers / listDimensionMembers', () => {
+  const dailyTemplate = [{ fieldId: 'b-vitals', key: 'vitals', label: 'Vitals', builtin: true, active: true }];
+  const statuses = [{ date: '2026-07-01T00:00:00.000Z', animal_id: 'a1', analysis_summary: { total: 1 } }];
+  const animals = [{ id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001' }];
+  it('wraps params with id/label/param/group', () => {
+    const m = listParameterMembers(dailyTemplate, statuses);
+    expect(m[0]).toMatchObject({ id: '__total__', label: 'Total attempts', group: 'metrics' });
+    expect(m[0].param).toMatchObject({ kind: 'total' });
+  });
+  it('dispatches by dimension', () => {
+    const ctx = { statuses, animals, dailyTemplate, groupField: '__none__' };
+    expect(listDimensionMembers('date', ctx).map((d) => d.id)).toEqual(['2026-07-01']);
+    expect(listDimensionMembers('subject', ctx).map((d) => d.id)).toEqual(['a1']);
+    expect(listDimensionMembers('parameter', ctx)[0].id).toBe('__total__');
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "listSubjectMembers"`
+Expected: FAIL — `listSubjectMembers is not defined`.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Add to `frontend/src/lib/dataExport.js` (after `buildStatusIndex`):
+
+```js
+export function listSubjectMembers(animals, groupField) {
+  const list = [...(animals ?? [])];
+  const nameCounts = new Map();
+  for (const a of list) {
+    const n = a?.animal_name ?? '';
+    nameCounts.set(n, (nameCounts.get(n) ?? 0) + 1);
+  }
+  const members = list.map((a) => {
+    const name = a?.animal_name ?? '';
+    const label = nameCounts.get(name) > 1 ? `${name} (${a?.animal_id_string ?? ''})` : name;
+    return { id: a.id, label, animalId: a.id, group: subjectGroupValue(a, groupField) };
+  });
+  const grouped = !!groupField && groupField !== '__none__';
+  members.sort((x, y) => {
+    if (grouped) {
+      const g = String(x.group ?? '').localeCompare(String(y.group ?? ''));
+      if (g !== 0) return g;
+    }
+    return String(x.label).localeCompare(String(y.label));
+  });
+  return members;
+}
+
+export function listParameterMembers(dailyTemplate, statuses) {
+  return listExportableParams(dailyTemplate, statuses).map((p) => ({
+    id: p.id, label: p.label, param: p, group: p.group,
+  }));
+}
+
+export function listDimensionMembers(dim, { statuses, animals, dailyTemplate, groupField }) {
+  if (dim === 'date') return listDateMembers(statuses);
+  if (dim === 'subject') return listSubjectMembers(animals, groupField);
+  if (dim === 'parameter') return listParameterMembers(dailyTemplate, statuses);
+  return [];
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS (all suites green).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): subject/parameter members + dimension dispatcher"
+```
+
+---
+
+### Task 3: Generalized buildMatrix
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (replace the existing `buildMatrix`)
+- Test: `frontend/tests/dataExport.test.js` (replace the existing `describe('buildMatrix', ...)` block)
+
+**Interfaces:**
+- Consumes: `buildStatusIndex`, `listDimensionMembers`, `otherDimension`, `dimLabel`, `extractValue`, `hasValue`.
+- Produces:
+  `buildMatrix(config, ctx)` where
+  - `config = { rowDim, colDim, pinnedMember, groupField }`
+  - `ctx = { statuses, animals, dailyTemplate }`
+  - returns `{ rowDim, colDim, pinnedDim, corner: string, context: { label, value }, groupAxis: 'row'|'col'|null, columns: Array<{ id, label, group }>, rows: Array<{ member: { id, label, group }, values: Array<value|''> }> }`
+- Empty-member rule: subject members always kept; date/parameter rows and columns dropped when entirely blank.
+- `groupAxis`: `'row'` when `rowDim === 'subject'` and grouping on; `'col'` when `colDim === 'subject'` and grouping on; else `null`.
+
+- [ ] **Step 1: Replace the failing tests**
+
+In `frontend/tests/dataExport.test.js`, **delete the entire existing `describe('buildMatrix', ...)` block** (the one using the old `buildMatrix(statuses, animals, totalParam)` signature) and the `const totalParam = ...` line, then add:
+
+```js
+const gAnimals = [
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+];
+const gStatuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 5, success_rate: 0.5 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 9, success_rate: 0.9 } },
+  { animal_id: 'a1', date: '2026-07-02T00:00:00.000Z', analysis_summary: { total: 7, success_rate: 0.7 } },
+];
+const ctx = { statuses: gStatuses, animals: gAnimals, dailyTemplate: [] };
+const totalMember = { id: '__total__', label: 'Total attempts', param: { kind: 'total' }, group: 'metrics' };
+
+describe('buildMatrix', () => {
+  it('default preset: rows=date, cols=subject, pinned=parameter (legacy layout)', () => {
+    const m = buildMatrix({ rowDim: 'date', colDim: 'subject', pinnedMember: totalMember, groupField: '__none__' }, ctx);
+    expect(m.corner).toBe('Date');
+    expect(m.context).toEqual({ label: 'Parameter', value: 'Total attempts' });
+    expect(m.columns.map((c) => c.label)).toEqual(['Alpha', 'Beta']);
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01', '2026-07-02']);
+    expect(m.rows[0].values).toEqual([5, 9]);
+    expect(m.rows[1].values).toEqual([7, '']); // Beta blank on 07-02
+    expect(m.groupAxis).toBeNull();
+  });
+
+  it('drops blank date rows but keeps all subject columns', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 0 } }, // 0 is a value
+      { animal_id: 'a1', date: '2026-07-03T00:00:00.000Z', analysis_summary: null },          // no value
+    ];
+    const m = buildMatrix({ rowDim: 'date', colDim: 'subject', pinnedMember: totalMember, groupField: '__none__' },
+      { statuses, animals: gAnimals, dailyTemplate: [] });
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01']);
+    expect(m.columns.length).toBe(2);
+    expect(m.rows[0].values).toEqual([0, '']);
+  });
+
+  it('subject as columns sets groupAxis=col and clusters subjects', () => {
+    const m = buildMatrix({ rowDim: 'date', colDim: 'subject', pinnedMember: totalMember, groupField: 'grp' }, ctx);
+    expect(m.groupAxis).toBe('col');
+    expect(m.columns.map((c) => [c.group, c.label])).toEqual([['Control', 'Alpha'], ['Drug', 'Beta']]);
+  });
+
+  it('subject as rows sets groupAxis=row; pinned date; cols=parameter', () => {
+    const dateMember = { id: '2026-07-01', label: '2026-07-01', dateKey: '2026-07-01' };
+    const m = buildMatrix({ rowDim: 'subject', colDim: 'parameter', pinnedMember: dateMember, groupField: 'grp' },
+      { statuses: gStatuses, animals: gAnimals, dailyTemplate: [] });
+    expect(m.corner).toBe('Subject');
+    expect(m.context).toEqual({ label: 'Date', value: '2026-07-01' });
+    expect(m.groupAxis).toBe('row');
+    expect(m.rows.map((r) => [r.member.group, r.member.label])).toEqual([['Control', 'Alpha'], ['Drug', 'Beta']]);
+    // columns are parameters (Total attempts, Success rate); Alpha on 07-01: total 5, rate 0.5
+    const totalCol = m.columns.findIndex((c) => c.label === 'Total attempts');
+    expect(m.rows[0].values[totalCol]).toBe(5);
+  });
+
+  it('drops blank parameter columns (params always dropped when empty)', () => {
+    // dailyTemplate adds a custom field with no data anywhere -> its column drops
+    const dailyTemplate = [{ fieldId: 'c-x', key: 'x', label: 'X', builtin: false, active: true }];
+    const dateMember = { id: '2026-07-01', label: '2026-07-01', dateKey: '2026-07-01' };
+    const m = buildMatrix({ rowDim: 'subject', colDim: 'parameter', pinnedMember: dateMember, groupField: '__none__' },
+      { statuses: gStatuses, animals: gAnimals, dailyTemplate });
+    expect(m.columns.map((c) => c.label)).not.toContain('X');
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "buildMatrix"`
+Expected: FAIL — new call shape not yet implemented (old `buildMatrix` returns `columns[].header`, no `context`).
+
+- [ ] **Step 3: Replace the implementation**
+
+In `frontend/src/lib/dataExport.js`, **delete the old `buildMatrix` function** (the `export function buildMatrix(statuses, animals, param) { ... }` block and its doc comment) and replace with:
+
+```js
+// Pivot statuses into a 2-D matrix per the chosen row/column dimensions.
+// The leftover (pinned) dimension is fixed to pinnedMember. Every cell resolves
+// a (dateKey, animalId, param) triple through the status index.
+export function buildMatrix(config, ctx) {
+  const { rowDim, colDim, pinnedMember, groupField } = config;
+  const pinnedDim = otherDimension(rowDim, colDim);
+  const index = buildStatusIndex(ctx.statuses);
+  const full = { ...ctx, groupField };
+  const rowMembers = listDimensionMembers(rowDim, full);
+  const colMembers = listDimensionMembers(colDim, full);
+
+  const cellValue = (rowM, colM) => {
+    const byDim = { [rowDim]: rowM, [colDim]: colM, [pinnedDim]: pinnedMember };
+    const dk = byDim.date?.dateKey ?? null;
+    const animalId = byDim.subject?.animalId ?? null;
+    const param = byDim.parameter?.param ?? null;
+    if (dk === null || animalId === null || animalId === undefined || !param) return '';
+    const status = index.get(dk)?.get(animalId);
+    if (!status) return '';
+    const v = extractValue(status, param);
+    return hasValue(v) ? v : '';
+  };
+
+  let rows = rowMembers.map((rowM) => ({
+    member: rowM,
+    values: colMembers.map((colM) => cellValue(rowM, colM)),
+  }));
+
+  // Empty-member rule: keep all subjects; drop entirely-blank date/parameter rows & columns.
+  if (rowDim !== 'subject') rows = rows.filter((r) => r.values.some((v) => v !== ''));
+
+  let keptCols = colMembers.map((_, i) => i);
+  if (colDim !== 'subject') keptCols = keptCols.filter((i) => rows.some((r) => r.values[i] !== ''));
+  const columns = keptCols.map((i) => colMembers[i]);
+  rows = rows.map((r) => ({ member: r.member, values: keptCols.map((i) => r.values[i]) }));
+
+  const grouped = !!groupField && groupField !== '__none__';
+  const groupAxis = grouped
+    ? (rowDim === 'subject' ? 'row' : colDim === 'subject' ? 'col' : null)
+    : null;
+
+  return {
+    rowDim,
+    colDim,
+    pinnedDim,
+    corner: dimLabel(rowDim),
+    context: { label: dimLabel(pinnedDim), value: pinnedMember?.label ?? '' },
+    groupAxis,
+    columns,
+    rows,
+  };
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS. (The `toCSV` suite still passes — it builds its own matrix literals and does not call `buildMatrix`; it is rewritten in Task 4.)
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): generalized buildMatrix over assignable dimensions"
+```
+
+---
+
+### Task 4: toCSV with context line + group cell
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (replace `toCSV`; leave `csvFilename` unchanged)
+- Test: `frontend/tests/dataExport.test.js` (replace the existing `describe('toCSV', ...)` block)
+
+**Interfaces:**
+- Consumes: `escapeCsvCell` (existing), matrix shape from Task 3.
+- Produces: `toCSV(matrix): string` — context line, blank line, optional group row (groupAxis==='col'), header row, data rows. Header/data gain a leading `Group` column when groupAxis==='row'. `csvFilename(title, label)` unchanged.
+
+- [ ] **Step 1: Replace the failing tests**
+
+In `frontend/tests/dataExport.test.js`, **delete the existing `describe('toCSV', ...)` block** and add:
+
+```js
+describe('toCSV', () => {
+  it('emits context line, blank line, header, data (no group)', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Total attempts' },
+      groupAxis: null,
+      columns: [{ id: 'a1', label: 'Alpha', group: null }, { id: 'a2', label: 'Beta', group: null }],
+      rows: [{ member: { label: '2026-07-01' }, values: [5, ''] }, { member: { label: '2026-07-02' }, values: ['', 9] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,Total attempts\n\nDate,Alpha,Beta\n2026-07-01,5,\n2026-07-02,,9',
+    );
+  });
+
+  it('adds a Group header row when subjects are columns', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Total attempts' },
+      groupAxis: 'col',
+      columns: [{ id: 'a1', label: 'Alpha', group: 'Control' }, { id: 'a2', label: 'Beta', group: 'Drug' }],
+      rows: [{ member: { label: '2026-07-01' }, values: [5, 9] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,Total attempts\n\nGroup,Control,Drug\nDate,Alpha,Beta\n2026-07-01,5,9',
+    );
+  });
+
+  it('adds a leading Group column when subjects are rows', () => {
+    const matrix = {
+      corner: 'Subject',
+      context: { label: 'Date', value: '2026-07-01' },
+      groupAxis: 'row',
+      columns: [{ id: 'p1', label: 'Total attempts', group: 'metrics' }],
+      rows: [
+        { member: { label: 'Alpha', group: 'Control' }, values: [5] },
+        { member: { label: 'Beta', group: 'Drug' }, values: [9] },
+      ],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Date,2026-07-01\n\nGroup,Subject,Total attempts\nControl,Alpha,5\nDrug,Beta,9',
+    );
+  });
+
+  it('escapes commas, quotes, and newlines per RFC 4180', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Note, field' },
+      groupAxis: null,
+      columns: [{ id: 'a1', label: 'he said "hi"', group: null }],
+      rows: [{ member: { label: '2026-07-01' }, values: ['line1\nline2'] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,"Note, field"\n\nDate,"he said ""hi"""\n2026-07-01,"line1\nline2"',
+    );
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "toCSV"`
+Expected: FAIL — old `toCSV` emits `Date,Alpha,Beta\n...` with no context line.
+
+- [ ] **Step 3: Replace the implementation**
+
+In `frontend/src/lib/dataExport.js`, **delete the old `toCSV` function** and its doc comment, and replace with:
+
+```js
+// Serialize a matrix to an RFC-4180-ish CSV string (LF line endings):
+//   <pinned label>,<pinned value>
+//   (blank line)
+//   [Group,<group per subject column>]    -- only when groupAxis === 'col'
+//   <corner>[,Group?],<column headers...>
+//   <row label>[,group?],<values...>
+export function toCSV(matrix) {
+  const lines = [];
+  lines.push([matrix.context.label, matrix.context.value].map(escapeCsvCell).join(','));
+  lines.push('');
+
+  if (matrix.groupAxis === 'col') {
+    const groupRow = ['Group', ...matrix.columns.map((c) => c.group ?? '—')];
+    lines.push(groupRow.map(escapeCsvCell).join(','));
+  }
+
+  const header = matrix.groupAxis === 'row'
+    ? ['Group', matrix.corner, ...matrix.columns.map((c) => c.label)]
+    : [matrix.corner, ...matrix.columns.map((c) => c.label)];
+  lines.push(header.map(escapeCsvCell).join(','));
+
+  for (const r of matrix.rows) {
+    const lead = matrix.groupAxis === 'row'
+      ? [r.member.group ?? '—', r.member.label]
+      : [r.member.label];
+    lines.push([...lead, ...r.values].map(escapeCsvCell).join(','));
+  }
+
+  return lines.join('\n');
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS (all suites, including the unchanged `csvFilename` and `extractValue` suites).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): toCSV emits context line + subject group cell"
+```
+
+---
+
+### Task 5: Rewrite ExportDataModal with axis + group controls
+
+**Files:**
+- Modify: `frontend/src/components/ExportDataModal.jsx` (full rewrite of the body; keep `triggerDownload`)
+- Test: `frontend/tests/ExportDataModal.test.jsx` (create)
+
+**Interfaces:**
+- Consumes: `EXPORT_DIMENSIONS`, `dimLabel`, `otherDimension`, `listDimensionMembers`, `buildMatrix`, `toCSV`, `csvFilename` from `../lib/dataExport`; `experimentsApi.getDailyStatuses` from `../api/client`.
+- New props: `subjectTemplate` (array of `{ fieldId, label, active }`), `groupField` (string, the experiment's saved default). Existing props unchanged: `experimentTitle`, `experimentId`, `dailyTemplate`, `animals`, `onClose`.
+- Produces: rendered modal. Default selection reproduces the legacy layout.
+
+- [ ] **Step 1: Write the failing component test**
+
+Create `frontend/tests/ExportDataModal.test.jsx`:
+
+```jsx
+import React from 'react';
+import { render, screen, waitFor, fireEvent } from '@testing-library/react';
+import ExportDataModal from '../src/components/ExportDataModal';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  experimentsApi: { getDailyStatuses: jest.fn() },
+}));
+
+const animals = [
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+];
+const statuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 5 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00.000Z', analysis_summary: { total: 9 } },
+];
+const subjectTemplate = [{ fieldId: 'grp', label: 'Group', active: true }];
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  client.experimentsApi.getDailyStatuses.mockResolvedValue(statuses);
+});
+
+function renderModal(props = {}) {
+  return render(
+    <ExportDataModal
+      experimentId="exp-1"
+      experimentTitle="My Study"
+      dailyTemplate={[]}
+      animals={animals}
+      subjectTemplate={subjectTemplate}
+      groupField="__none__"
+      onClose={jest.fn()}
+      {...props}
+    />,
+  );
+}
+
+describe('ExportDataModal', () => {
+  it('defaults to Rows=Date, Columns=Subject and shows the preview', async () => {
+    renderModal();
+    expect(await screen.findByLabelText('Rows')).toHaveValue('date');
+    expect(screen.getByLabelText('Columns')).toHaveValue('subject');
+    await waitFor(() => expect(screen.getByText(/1 date.*2 subjects/i)).toBeInTheDocument());
+  });
+
+  it('hides the Group by control until Subject is an axis', async () => {
+    renderModal();
+    await screen.findByLabelText('Rows');
+    // subject is a column by default -> Group by visible
+    expect(screen.getByLabelText('Group by')).toBeInTheDocument();
+    // move subject off both axes: Rows=Date, Columns=Parameter -> subject pinned
+    fireEvent.change(screen.getByLabelText('Columns'), { target: { value: 'parameter' } });
+    await waitFor(() => expect(screen.queryByLabelText('Group by')).not.toBeInTheDocument());
+  });
+
+  it('keeps row and column dimensions distinct', async () => {
+    renderModal();
+    const rows = await screen.findByLabelText('Rows');
+    fireEvent.change(rows, { target: { value: 'subject' } }); // collides with column=subject
+    await waitFor(() => expect(screen.getByLabelText('Columns')).not.toHaveValue('subject'));
+  });
+});
+```
+
+- [ ] **Step 2: Run test to verify it fails**
+
+Run: `npx jest tests/ExportDataModal.test.jsx`
+Expected: FAIL — modal has no `Rows`/`Columns`/`Group by` labels yet.
+
+- [ ] **Step 3: Rewrite the component**
+
+Replace the body of `frontend/src/components/ExportDataModal.jsx` (keep the top `triggerDownload` helper exactly as-is) with this component:
+
+```jsx
+import React, { useEffect, useMemo, useState } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+import {
+  EXPORT_DIMENSIONS, dimLabel, otherDimension,
+  listDimensionMembers, buildMatrix, toCSV, csvFilename,
+} from '../lib/dataExport';
+
+const PARAM_GROUP_LABELS = { metrics: 'Session metrics', daily: 'Daily record fields' };
+
+export default function ExportDataModal({
+  experimentTitle, experimentId, dailyTemplate, animals, subjectTemplate = [], groupField = '__none__', onClose,
+}) {
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [statuses, setStatuses] = useState([]);
+
+  const [rowDim, setRowDim] = useState('date');
+  const [colDim, setColDim] = useState('subject');
+  const [pinnedId, setPinnedId] = useState(null);
+  const [groupBy, setGroupBy] = useState(groupField ?? '__none__');
+
+  useEffect(() => {
+    let alive = true;
+    setLoading(true);
+    setError(null);
+    experimentsApi.getDailyStatuses(experimentId, {})
+      .then((data) => { if (alive) setStatuses(data); })
+      .catch((err) => { if (alive) setError(err.message); })
+      .finally(() => { if (alive) setLoading(false); });
+    return () => { alive = false; };
+  }, [experimentId]);
+
+  const pinnedDim = otherDimension(rowDim, colDim);
+  const subjectIsAxis = rowDim === 'subject' || colDim === 'subject';
+  const effGroup = subjectIsAxis ? groupBy : '__none__';
+  const ctx = useMemo(() => ({ statuses, animals, dailyTemplate }), [statuses, animals, dailyTemplate]);
+
+  // Members of the pinned dimension populate its value dropdown.
+  const pinnedMembers = useMemo(
+    () => listDimensionMembers(pinnedDim, { ...ctx, groupField: effGroup }),
+    [pinnedDim, ctx, effGroup],
+  );
+  const effPinnedId = pinnedId ?? pinnedMembers[0]?.id ?? null;
+  const pinnedMember = pinnedMembers.find((m) => m.id === effPinnedId) ?? pinnedMembers[0] ?? null;
+
+  const matrix = useMemo(
+    () => (pinnedMember
+      ? buildMatrix({ rowDim, colDim, pinnedMember, groupField: effGroup }, ctx)
+      : { columns: [], rows: [], context: { label: '', value: '' }, corner: '', groupAxis: null }),
+    [rowDim, colDim, pinnedMember, effGroup, ctx],
+  );
+  const hasData = matrix.rows.length > 0;
+
+  // When the user changes an axis, keep the two distinct and reset the pinned pick.
+  function changeRowDim(next) {
+    setRowDim(next);
+    if (colDim === next) setColDim(otherDimension(next, null) ?? EXPORT_DIMENSIONS.find((d) => d.dim !== next).dim);
+    setPinnedId(null);
+  }
+  function changeColDim(next) {
+    setColDim(next);
+    if (rowDim === next) setRowDim(EXPORT_DIMENSIONS.find((d) => d.dim !== next).dim);
+    setPinnedId(null);
+  }
+
+  function handleExport() {
+    if (!hasData || !pinnedMember) return;
+    triggerDownload(csvFilename(experimentTitle, pinnedMember.label), toCSV(matrix));
+    onClose();
+  }
+
+  if (loading) return <p className="text-sm text-gray-400" aria-live="polite">Loading data…</p>;
+  if (error) return (
+    <div className="space-y-4">
+      <Alert type="error" message={error} />
+      <div className="flex justify-end"><Button variant="secondary" onClick={onClose}>Close</Button></div>
+    </div>
+  );
+
+  const selectCls = 'w-full border border-gray-200 rounded px-2 py-1.5 text-sm bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400';
+  const colOptions = EXPORT_DIMENSIONS.filter((d) => d.dim !== rowDim);
+
+  return (
+    <div className="space-y-4">
+      <p className="text-sm text-gray-500">
+        Choose what goes on the rows and columns. The remaining dimension is fixed to one value, shown at the top of the file.
+      </p>
+
+      <div className="grid grid-cols-2 gap-3">
+        <div>
+          <label htmlFor="export-rows" className="block text-xs font-medium text-gray-500 mb-1">Rows</label>
+          <select id="export-rows" value={rowDim} onChange={(e) => changeRowDim(e.target.value)} className={selectCls}>
+            {EXPORT_DIMENSIONS.map((d) => <option key={d.dim} value={d.dim}>{d.label}</option>)}
+          </select>
+        </div>
+        <div>
+          <label htmlFor="export-cols" className="block text-xs font-medium text-gray-500 mb-1">Columns</label>
+          <select id="export-cols" value={colDim} onChange={(e) => changeColDim(e.target.value)} className={selectCls}>
+            {colOptions.map((d) => <option key={d.dim} value={d.dim}>{d.label}</option>)}
+          </select>
+        </div>
+      </div>
+
+      <div>
+        <label htmlFor="export-pinned" className="block text-xs font-medium text-gray-500 mb-1">
+          Fixed: {dimLabel(pinnedDim)}
+        </label>
+        <select
+          id="export-pinned"
+          value={effPinnedId ?? ''}
+          onChange={(e) => setPinnedId(e.target.value)}
+          className={selectCls}
+        >
+          {pinnedDim === 'parameter'
+            ? groupParamMembers(pinnedMembers).map((g) => (
+                <optgroup key={g.group} label={PARAM_GROUP_LABELS[g.group] ?? g.group}>
+                  {g.items.map((m) => <option key={m.id} value={m.id}>{m.label}</option>)}
+                </optgroup>
+              ))
+            : pinnedMembers.map((m) => <option key={m.id} value={m.id}>{m.label}</option>)}
+        </select>
+      </div>
+
+      {subjectIsAxis && (
+        <div>
+          <label htmlFor="export-group" className="block text-xs font-medium text-gray-500 mb-1">Group by</label>
+          <select id="export-group" value={groupBy} onChange={(e) => setGroupBy(e.target.value)} className={selectCls}>
+            <option value="__none__">— None —</option>
+            <option value="__name__">Name</option>
+            <option value="__id__">Subject ID</option>
+            {subjectTemplate.filter((f) => f.active).map((f) => (
+              <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+            ))}
+          </select>
+        </div>
+      )}
+
+      <p className="text-xs text-gray-400">
+        {hasData
+          ? `${matrix.rows.length} ${matrix.corner.toLowerCase()}${matrix.rows.length !== 1 ? 's' : ''} × ${matrix.columns.length} ${dimLabel(colDim).toLowerCase()}${matrix.columns.length !== 1 ? 's' : ''}`
+          : 'No data for this selection yet.'}
+      </p>
+
+      <div className="flex justify-end gap-2 pt-2">
+        <Button variant="secondary" onClick={onClose}>Cancel</Button>
+        <Button onClick={handleExport} disabled={!hasData}>Export CSV</Button>
+      </div>
+    </div>
+  );
+}
+
+// Group parameter members by their .group for <optgroup> rendering, preserving order.
+function groupParamMembers(members) {
+  const out = [];
+  for (const m of members) {
+    let g = out.find((x) => x.group === m.group);
+    if (!g) { g = { group: m.group, items: [] }; out.push(g); }
+    g.items.push(m);
+  }
+  return out;
+}
+```
+
+Note: the preview test matches `/1 date.*2 subjects/i` — the corner is `Date` (→ "date"/"dates") and `dimLabel(colDim)` is `Subject` (→ "subject"/"subjects"). Confirm the string reads "1 date × 2 subjects".
+
+- [ ] **Step 4: Run test to verify it passes**
+
+Run: `npx jest tests/ExportDataModal.test.jsx`
+Expected: PASS (all three cases).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/components/ExportDataModal.jsx frontend/tests/ExportDataModal.test.jsx
+git commit -m "feat(export): modal gains assignable axes + group-by control"
+```
+
+---
+
+### Task 6: Wire new props from ExperimentDetail
+
+**Files:**
+- Modify: `frontend/src/pages/ExperimentDetail.jsx` (the `<ExportDataModal ... />` render, ~line 414)
+
+**Interfaces:**
+- Consumes: `subjectTemplate` state and `groupField` state (both already present in `ExperimentDetail`).
+- Produces: passes `subjectTemplate={subjectTemplate}` and `groupField={groupField}` to `ExportDataModal`.
+
+- [ ] **Step 1: Add the two props**
+
+In `frontend/src/pages/ExperimentDetail.jsx`, change the `<ExportDataModal>` element to:
+
+```jsx
+        <ExportDataModal
+          experimentId={id}
+          experimentTitle={experiment.title}
+          dailyTemplate={dailyTemplate}
+          animals={animals}
+          subjectTemplate={subjectTemplate}
+          groupField={groupField}
+          onClose={() => setShowExport(false)}
+        />
+```
+
+- [ ] **Step 2: Run the full frontend test suite**
+
+Run: `npm test`
+Expected: PASS — full suite green, including `dataExport` and `ExportDataModal`.
+
+- [ ] **Step 3: Manual smoke check**
+
+Run: `npm run dev`, open an experiment with daily data, click **Export data**. Verify: default download matches the old date×subject×parameter layout; switching Rows/Columns updates the preview; the fixed-value dropdown lists the third dimension; a group-by choice adds the Group row/column and the top context line reads e.g. `Subject,Mouse-01`.
+
+- [ ] **Step 4: Commit**
+
+```bash
+git add frontend/src/pages/ExperimentDetail.jsx
+git commit -m "feat(export): pass subjectTemplate + saved group field to export modal"
+```
+
+---
+
+## Self-Review Notes
+
+- **Spec coverage:** assignable axes (Tasks 1–3, 5) · pinned third dimension + value picker (Tasks 3, 5) · beginning-only context line (Task 4) · subject group cell on the subject axis, clustered by group (Tasks 2–4) · Group-by dropdown defaulting to saved field, shown only when Subject is an axis (Tasks 5–6) · keep-subjects/drop-blank-date-and-param rule (Task 3) · default reproduces legacy layout (Tasks 3, 5). All covered.
+- **Type consistency:** member shape `{ id, label, ... }` and matrix shape `{ context, corner, groupAxis, columns:[{id,label,group}], rows:[{member,values}] }` are used identically across Tasks 3–5.
+- **Out of scope (per spec):** multi-value stacking, footer repeat, experiment-level metadata block, persisting axis choices.

docs/superpowers/plans/2026-07-19-subject-series-export.md

@@ -0,0 +1,668 @@
+# Subject-Series Data Export Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Replace the export modal's assignable-axes UI with three pickers — X field (rows), Data value (cells), and Group by — where columns are always the subjects, matching the cross-subject metrics plot.
+
+**Architecture:** Add X-coordinate helpers to `dataExport.js` (`numericFieldVal`, `listSampleMembers`, `buildSampleIndex`) and a focused `buildSubjectSeriesMatrix` that emits the existing `toCSV` shape. Rewrite `ExportDataModal.jsx` to the three pickers. Then delete the now-dead assignable-axes machinery.
+
+**Tech Stack:** React 18, plain ES modules, Jest + `@testing-library/react` (jsdom). No new dependencies.
+
+**Spec:** `docs/superpowers/specs/2026-07-19-subject-series-export-design.md`
+
+## Global Constraints
+
+- `dataExport.js` stays pure: no React, no I/O.
+- Cell value semantics: `0` and `''` are **real** values; only genuinely-missing lookups render blank (`''`), via the existing `hasValue` + `extractValue`.
+- CSV: LF (`\n`) line endings; escape every cell via the existing `escapeCsvCell`.
+- **X = `Date`** → rows are distinct `YYYY-MM-DD` dates, sorted.
+- **X = `# Days Reach`** (`'__days__'`) → rows are `1, 2, 3, …`; the max over subjects of that subject's count of recorded statuses (a status must have `animal_id` and `date`). A cell for `(subject, N)` reads the subject's Nth recorded day, counting **all** records sorted ascending by date (per-status ordinal, Day 1 = earliest).
+- **X = daily field** (its `fieldId`) → rows are the distinct **numeric** values (`numericFieldVal`), sorted ascending; non-numeric excluded. A cell for `(subject, v)` reads that subject's first status (by date) whose field equals `v`.
+- Columns are **always** the subjects (`listSubjectMembers`), clustered by group then name. Entirely-blank sample rows are dropped; subject columns are always kept.
+- Group by defaults to the saved field (`groupField` prop), validated against `__none__`/`__name__`/`__id__`/active `subjectTemplate` fields; coerced to `__none__` when unset or stale.
+- CSV: line 1 is `Data,<metric label>`; blank line; a `Group,…` row only when grouping (missing group → `—`); header `= <X label>,<subject headers…>`; data rows `= <X value>,<values…>`. Filename via existing `csvFilename(title, dataLabel)`.
+- Default X = `Date`; default Data = first parameter (`Total attempts`).
+- Run tests from `frontend/`: `npx jest tests/dataExport.test.js`, `npx jest tests/ExportDataModal.test.jsx`, full `npm test`.
+- Two suites (`tests/ExperimentCalendar.test.jsx`, `tests/ExperimentDayView.test.jsx`, 31 tests) fail for a PRE-EXISTING, unrelated reason and must be left as-is; changes must introduce no new failures.
+
+---
+
+### Task 1: X-coordinate helpers
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (add three exports; keep everything else for now)
+- Test: `frontend/tests/dataExport.test.js`
+
+**Interfaces:**
+- Consumes: existing private `dateKey(date)`.
+- Produces:
+  - `numericFieldVal(status, field): number|null` — `field.builtin ? status[field.key] : status.custom_fields[field.fieldId]`, `parseFloat`, non-numeric → null.
+  - `listSampleMembers(statuses, xField, dailyTemplate): Array<{ id, label, sampleValue }>` — row members for the chosen X (`xField` is `'__date__'`, `'__days__'`, or a daily `fieldId`).
+  - `buildSampleIndex(statuses, xField, dailyTemplate): Map<animalId, Map<sampleValue, status>>` — first status per `(subject, sampleValue)` wins, per-subject date-ordered.
+
+- [ ] **Step 1: Write the failing tests**
+
+Append to `frontend/tests/dataExport.test.js`:
+
+```js
+import { numericFieldVal, listSampleMembers, buildSampleIndex } from '../src/lib/dataExport';
+
+const sDaily = [{ fieldId: 'c-w', key: 'w', label: 'Weight', builtin: false, active: true }];
+const sStatuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', custom_fields: { 'c-w': '250' } },
+  { animal_id: 'a1', date: '2026-07-03T00:00:00Z', custom_fields: { 'c-w': '260' } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', custom_fields: { 'c-w': '250' } },
+];
+
+describe('numericFieldVal', () => {
+  it('reads builtin via key and custom via fieldId, parsed to number', () => {
+    expect(numericFieldVal({ weight: '250' }, { builtin: true, key: 'weight' })).toBe(250);
+    expect(numericFieldVal({ custom_fields: { 'c-w': '12.5' } }, { builtin: false, fieldId: 'c-w' })).toBe(12.5);
+  });
+  it('returns null for non-numeric, missing, or no field', () => {
+    expect(numericFieldVal({ custom_fields: { 'c-w': 'abc' } }, { builtin: false, fieldId: 'c-w' })).toBeNull();
+    expect(numericFieldVal({}, { builtin: true, key: 'weight' })).toBeNull();
+    expect(numericFieldVal({ weight: 1 }, null)).toBeNull();
+  });
+});
+
+describe('listSampleMembers', () => {
+  it('date: distinct dates sorted', () => {
+    expect(listSampleMembers(sStatuses, '__date__', sDaily).map((m) => m.sampleValue)).toEqual(['2026-07-01', '2026-07-03']);
+  });
+  it('# days reach: 1..max records per subject', () => {
+    expect(listSampleMembers(sStatuses, '__days__', sDaily).map((m) => m.sampleValue)).toEqual([1, 2]);
+  });
+  it('daily field: distinct numeric values sorted ascending', () => {
+    expect(listSampleMembers(sStatuses, 'c-w', sDaily).map((m) => m.sampleValue)).toEqual([250, 260]);
+  });
+});
+
+describe('buildSampleIndex', () => {
+  it('date coord maps animalId -> dateKey -> status', () => {
+    const idx = buildSampleIndex(sStatuses, '__date__', sDaily);
+    expect(idx.get('a1').get('2026-07-03').date).toContain('2026-07-03');
+  });
+  it('# days reach assigns per-subject ordinals in date order', () => {
+    const idx = buildSampleIndex(sStatuses, '__days__', sDaily);
+    expect(idx.get('a1').get(1).date).toContain('2026-07-01');
+    expect(idx.get('a1').get(2).date).toContain('2026-07-03');
+    expect(idx.get('a2').get(1).date).toContain('2026-07-01');
+    expect(idx.get('a2').has(2)).toBe(false);
+  });
+  it('daily field maps numeric value to first status by date', () => {
+    const idx = buildSampleIndex(sStatuses, 'c-w', sDaily);
+    expect(idx.get('a1').get(250).date).toContain('2026-07-01');
+    expect(idx.get('a1').get(260).date).toContain('2026-07-03');
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "listSampleMembers"`
+Expected: FAIL — `listSampleMembers is not defined`.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Add to `frontend/src/lib/dataExport.js` (after `listExportableParams`, before the private `hasValue`/`dateKey` — note `dateKey` is defined lower in the file but hoisted as a function declaration, so referencing it here is fine):
+
+```js
+// Numeric value of a daily field on one status (mirrors the metrics plot's helper).
+export function numericFieldVal(status, field) {
+  if (!field) return null;
+  const raw = field.builtin ? status?.[field.key] : status?.custom_fields?.[field.fieldId];
+  const n = parseFloat(raw);
+  return Number.isNaN(n) ? null : n;
+}
+
+// Ordered row members for the chosen X coordinate.
+// xField: '__date__' | '__days__' | <daily fieldId>
+export function listSampleMembers(statuses, xField, dailyTemplate) {
+  const list = statuses ?? [];
+  if (xField === '__date__') {
+    const keys = new Set();
+    for (const s of list) if (s?.date) keys.add(dateKey(s.date));
+    return [...keys].sort().map((k) => ({ id: k, label: k, sampleValue: k }));
+  }
+  if (xField === '__days__') {
+    const counts = new Map();
+    for (const s of list) {
+      if (s?.animal_id == null || !s?.date) continue;
+      counts.set(s.animal_id, (counts.get(s.animal_id) ?? 0) + 1);
+    }
+    const max = counts.size ? Math.max(...counts.values()) : 0;
+    return Array.from({ length: max }, (_, i) => ({ id: String(i + 1), label: String(i + 1), sampleValue: i + 1 }));
+  }
+  const field = (dailyTemplate ?? []).find((f) => f.fieldId === xField);
+  const vals = new Set();
+  for (const s of list) {
+    const v = numericFieldVal(s, field);
+    if (v !== null) vals.add(v);
+  }
+  return [...vals].sort((a, b) => a - b).map((v) => ({ id: String(v), label: String(v), sampleValue: v }));
+}
+
+// animalId -> Map(sampleValue -> status). First status per (subject, sampleValue) wins,
+// scanning each subject's statuses in ascending date order.
+export function buildSampleIndex(statuses, xField, dailyTemplate) {
+  const bySubject = new Map();
+  for (const s of statuses ?? []) {
+    if (s?.animal_id == null || !s?.date) continue;
+    if (!bySubject.has(s.animal_id)) bySubject.set(s.animal_id, []);
+    bySubject.get(s.animal_id).push(s);
+  }
+  const field = xField !== '__date__' && xField !== '__days__'
+    ? (dailyTemplate ?? []).find((f) => f.fieldId === xField)
+    : null;
+
+  const index = new Map();
+  for (const [animalId, subjStatuses] of bySubject) {
+    const ordered = [...subjStatuses].sort((a, b) => dateKey(a.date).localeCompare(dateKey(b.date)));
+    const m = new Map();
+    ordered.forEach((s, i) => {
+      let key;
+      if (xField === '__date__') key = dateKey(s.date);
+      else if (xField === '__days__') key = i + 1;
+      else { const v = numericFieldVal(s, field); if (v === null) return; key = v; }
+      if (!m.has(key)) m.set(key, s);
+    });
+    index.set(animalId, m);
+  }
+  return index;
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS (new suites green; all pre-existing suites still green).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): X-coordinate helpers (date, # days reach, daily field)"
+```
+
+---
+
+### Task 2: buildSubjectSeriesMatrix
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (add `buildSubjectSeriesMatrix` + private `xFieldLabel`)
+- Test: `frontend/tests/dataExport.test.js`
+
+**Interfaces:**
+- Consumes: `listSubjectMembers`, `listSampleMembers`, `buildSampleIndex`, `extractValue`, private `hasValue`.
+- Produces: `buildSubjectSeriesMatrix({ xField, dataParam, groupField }, { statuses, animals, dailyTemplate })` → `{ corner, context: { label: 'Data', value }, groupAxis: 'col'|null, columns: [{ id, label, animalId, group }], rows: [{ member: { id, label, sampleValue }, values: [value|''] }] }` — the same shape the existing `toCSV` consumes (`groupAxis: 'col'` triggers its group-row branch).
+
+- [ ] **Step 1: Write the failing tests**
+
+Append to `frontend/tests/dataExport.test.js`:
+
+```js
+import { buildSubjectSeriesMatrix } from '../src/lib/dataExport';
+
+const ssAnimals = [
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+];
+const ssStatuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5 } },
+  { animal_id: 'a1', date: '2026-07-02T00:00:00Z', analysis_summary: { total: 7 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 9 } },
+];
+const totalParam = { id: '__total__', label: 'Total attempts', kind: 'total', group: 'metrics' };
+
+describe('buildSubjectSeriesMatrix', () => {
+  it('date X: subjects as columns, date rows, blank where missing, context names the metric', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: '__none__' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.corner).toBe('Date');
+    expect(m.context).toEqual({ label: 'Data', value: 'Total attempts' });
+    expect(m.groupAxis).toBeNull();
+    expect(m.columns.map((c) => c.label)).toEqual(['Alpha', 'Beta']);
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01', '2026-07-02']);
+    expect(m.rows[0].values).toEqual([5, 9]);
+    expect(m.rows[1].values).toEqual([7, '']);
+  });
+  it('# days reach X: rows align each subject by day ordinal', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__days__', dataParam: totalParam, groupField: '__none__' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.corner).toBe('# Days Reach');
+    expect(m.rows.map((r) => r.member.label)).toEqual(['1', '2']);
+    expect(m.rows[0].values).toEqual([5, 9]);
+    expect(m.rows[1].values).toEqual([7, '']);
+  });
+  it('grouping sets groupAxis col and clusters subjects', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: 'grp' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.groupAxis).toBe('col');
+    expect(m.columns.map((c) => [c.group, c.label])).toEqual([['Control', 'Alpha'], ['Drug', 'Beta']]);
+  });
+  it('drops entirely-blank rows', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5 } },
+      { animal_id: 'a1', date: '2026-07-05T00:00:00Z', analysis_summary: null },
+    ];
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: '__none__' },
+      { statuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01']);
+  });
+});
+```
+
+- [ ] **Step 2: Run tests to verify they fail**
+
+Run: `npx jest tests/dataExport.test.js -t "buildSubjectSeriesMatrix"`
+Expected: FAIL — `buildSubjectSeriesMatrix is not defined`.
+
+- [ ] **Step 3: Write minimal implementation**
+
+Add to `frontend/src/lib/dataExport.js` (after `buildSampleIndex`):
+
+```js
+function xFieldLabel(xField, dailyTemplate) {
+  if (xField === '__date__') return 'Date';
+  if (xField === '__days__') return '# Days Reach';
+  return (dailyTemplate ?? []).find((f) => f.fieldId === xField)?.label ?? '';
+}
+
+// Subjects as columns, X-field values as rows, one Data value per cell.
+// Returns the { context, corner, groupAxis, columns, rows } shape toCSV consumes.
+export function buildSubjectSeriesMatrix({ xField, dataParam, groupField }, { statuses, animals, dailyTemplate }) {
+  const columns = listSubjectMembers(animals, groupField);
+  const rowMembers = listSampleMembers(statuses, xField, dailyTemplate);
+  const index = buildSampleIndex(statuses, xField, dailyTemplate);
+
+  const cellValue = (sampleValue, animalId) => {
+    const status = index.get(animalId)?.get(sampleValue);
+    if (!status || !dataParam) return '';
+    const v = extractValue(status, dataParam);
+    return hasValue(v) ? v : '';
+  };
+
+  let rows = rowMembers.map((rm) => ({
+    member: rm,
+    values: columns.map((c) => cellValue(rm.sampleValue, c.animalId)),
+  }));
+  rows = rows.filter((r) => r.values.some((v) => v !== '')); // drop entirely-blank sample rows
+
+  const grouped = !!groupField && groupField !== '__none__';
+  return {
+    corner: xFieldLabel(xField, dailyTemplate),
+    context: { label: 'Data', value: dataParam?.label ?? '' },
+    groupAxis: grouped ? 'col' : null,
+    columns,
+    rows,
+  };
+}
+```
+
+- [ ] **Step 4: Run tests to verify they pass**
+
+Run: `npx jest tests/dataExport.test.js`
+Expected: PASS (all suites green).
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "feat(export): buildSubjectSeriesMatrix — subjects as columns over an X field"
+```
+
+---
+
+### Task 3: Rewrite ExportDataModal to the three pickers
+
+**Files:**
+- Modify: `frontend/src/components/ExportDataModal.jsx` (full body rewrite; keep `triggerDownload`)
+- Test: `frontend/tests/ExportDataModal.test.jsx` (rewrite)
+
+**Interfaces:**
+- Consumes: `listExportableParams`, `buildSubjectSeriesMatrix`, `toCSV`, `csvFilename` from `../lib/dataExport`; `experimentsApi.getDailyStatuses`.
+- Props unchanged: `experimentTitle`, `experimentId`, `dailyTemplate`, `animals`, `subjectTemplate` (default `[]`), `groupField` (default `'__none__'`), `onClose`.
+- Produces: modal with three selects — X (rows), Data (cells), Group by.
+
+- [ ] **Step 1: Rewrite the component test**
+
+Replace the entire contents of `frontend/tests/ExportDataModal.test.jsx` with:
+
+```jsx
+import React from 'react';
+import { render, screen, waitFor, fireEvent } from '@testing-library/react';
+import ExportDataModal from '../src/components/ExportDataModal';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  experimentsApi: { getDailyStatuses: jest.fn() },
+}));
+
+const animals = [
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+];
+const statuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5, success_rate: 0.5 } },
+  { animal_id: 'a1', date: '2026-07-02T00:00:00Z', analysis_summary: { total: 7, success_rate: 0.7 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 9, success_rate: 0.9 } },
+];
+const subjectTemplate = [{ fieldId: 'grp', label: 'Group', active: true }];
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  client.experimentsApi.getDailyStatuses.mockResolvedValue(statuses);
+});
+
+// Intercept the Blob handed to URL.createObjectURL so tests can read the real CSV.
+// Also stub anchor.click() — jsdom treats a click on <a href="blob:..."> as an
+// unimplemented navigation that throws async and can flake a later test.
+function mockDownload() {
+  let blob = null;
+  const origCreate = global.URL.createObjectURL;
+  const origRevoke = global.URL.revokeObjectURL;
+  const origClick = window.HTMLAnchorElement.prototype.click;
+  global.URL.createObjectURL = jest.fn((b) => { blob = b; return 'blob:mock'; });
+  global.URL.revokeObjectURL = jest.fn();
+  window.HTMLAnchorElement.prototype.click = jest.fn();
+  return {
+    getBlob: () => blob,
+    restore: async () => {
+      await new Promise((r) => setTimeout(r, 0)); // flush handleExport's setTimeout revoke
+      global.URL.createObjectURL = origCreate;
+      global.URL.revokeObjectURL = origRevoke;
+      window.HTMLAnchorElement.prototype.click = origClick;
+    },
+  };
+}
+
+function readBlobText(blob) {
+  return new Promise((resolve, reject) => {
+    const fr = new FileReader();
+    fr.onload = () => resolve(fr.result);
+    fr.onerror = reject;
+    fr.readAsText(blob);
+  });
+}
+
+function renderModal(props = {}) {
+  return render(
+    <ExportDataModal
+      experimentId="exp-1"
+      experimentTitle="My Study"
+      dailyTemplate={[]}
+      animals={animals}
+      subjectTemplate={subjectTemplate}
+      groupField="__none__"
+      onClose={jest.fn()}
+      {...props}
+    />,
+  );
+}
+
+describe('ExportDataModal', () => {
+  it('renders X / Data / Group by pickers; X defaults to Date', async () => {
+    renderModal();
+    expect(await screen.findByLabelText('X axis (rows)')).toHaveValue('__date__');
+    expect(screen.getByLabelText('Data (cells)')).toBeInTheDocument();
+    expect(screen.getByLabelText('Group by')).toHaveValue('__none__');
+    await waitFor(() => expect(screen.getByText(/2 rows × 2 subjects/i)).toBeInTheDocument());
+  });
+
+  it('default export (X=Date, Data=Total attempts) has subject columns, date rows, blank where missing', async () => {
+    const dl = mockDownload();
+    renderModal();
+    await screen.findByLabelText('X axis (rows)');
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toBe('Data,Total attempts\n\nDate,Alpha,Beta\n2026-07-01,5,9\n2026-07-02,7,');
+    await dl.restore();
+  });
+
+  it('switching X to # Days Reach makes rows the day ordinals', async () => {
+    const dl = mockDownload();
+    renderModal();
+    fireEvent.change(await screen.findByLabelText('X axis (rows)'), { target: { value: '__days__' } });
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toBe('Data,Total attempts\n\n# Days Reach,Alpha,Beta\n1,5,9\n2,7,');
+    await dl.restore();
+  });
+
+  it('a valid group field adds a Group row and clusters subjects', async () => {
+    const dl = mockDownload();
+    renderModal({ groupField: 'grp' });
+    await screen.findByLabelText('X axis (rows)');
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toMatch(/^Group,Control,Drug$/m);
+    await dl.restore();
+  });
+});
+```
+
+- [ ] **Step 2: Run the test to verify it fails**
+
+Run: `npx jest tests/ExportDataModal.test.jsx`
+Expected: FAIL — old modal has no `X axis (rows)` / `Data (cells)` labels.
+
+- [ ] **Step 3: Rewrite the component**
+
+Replace the entire contents of `frontend/src/components/ExportDataModal.jsx` with:
+
+```jsx
+import React, { useEffect, useMemo, useState } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+import { listExportableParams, buildSubjectSeriesMatrix, toCSV, csvFilename } from '../lib/dataExport';
+
+const PARAM_GROUP_LABELS = { metrics: 'Session metrics', daily: 'Daily record fields' };
+
+function triggerDownload(filename, text) {
+  const blob = new Blob([text], { type: 'text/csv;charset=utf-8;' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = filename;
+  document.body.appendChild(a);
+  a.click();
+  document.body.removeChild(a);
+  setTimeout(() => URL.revokeObjectURL(url), 0);
+}
+
+export default function ExportDataModal({
+  experimentTitle, experimentId, dailyTemplate, animals, subjectTemplate = [], groupField = '__none__', onClose,
+}) {
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [statuses, setStatuses] = useState([]);
+
+  const [xField, setXField] = useState('__date__');
+  const [dataId, setDataId] = useState(null);
+  const [groupBy, setGroupBy] = useState(() => {
+    const valid = groupField === '__none__' || groupField === '__name__' || groupField === '__id__'
+      || subjectTemplate.some((f) => f.active && f.fieldId === groupField);
+    return valid ? groupField : '__none__';
+  });
+
+  useEffect(() => {
+    let alive = true;
+    setLoading(true);
+    setError(null);
+    experimentsApi.getDailyStatuses(experimentId, {})
+      .then((data) => { if (alive) setStatuses(data); })
+      .catch((err) => { if (alive) setError(err.message); })
+      .finally(() => { if (alive) setLoading(false); });
+    return () => { alive = false; };
+  }, [experimentId]);
+
+  const params = useMemo(() => listExportableParams(dailyTemplate, statuses), [dailyTemplate, statuses]);
+  const effDataId = dataId ?? params[0]?.id ?? null;
+  const dataParam = params.find((p) => p.id === effDataId) ?? params[0] ?? null;
+
+  const activeDaily = useMemo(() => (dailyTemplate ?? []).filter((f) => f.active), [dailyTemplate]);
+  const xOptions = useMemo(() => [
+    { id: '__date__', label: 'Date' },
+    { id: '__days__', label: '# Days Reach' },
+    ...activeDaily.map((f) => ({ id: f.fieldId, label: f.label })),
+  ], [activeDaily]);
+
+  const matrix = useMemo(
+    () => (dataParam
+      ? buildSubjectSeriesMatrix({ xField, dataParam, groupField: groupBy }, { statuses, animals, dailyTemplate })
+      : { columns: [], rows: [], context: { label: 'Data', value: '' }, corner: '', groupAxis: null }),
+    [xField, dataParam, groupBy, statuses, animals, dailyTemplate],
+  );
+  const hasData = matrix.rows.length > 0;
+
+  const groupedParams = useMemo(() => {
+    const out = [];
+    for (const p of params) {
+      let g = out.find((x) => x.group === p.group);
+      if (!g) { g = { group: p.group, items: [] }; out.push(g); }
+      g.items.push(p);
+    }
+    return out;
+  }, [params]);
+
+  function handleExport() {
+    if (!hasData || !dataParam) return;
+    triggerDownload(csvFilename(experimentTitle, dataParam.label), toCSV(matrix));
+    onClose();
+  }
+
+  if (loading) return <p className="text-sm text-gray-400" aria-live="polite">Loading data…</p>;
+  if (error) return (
+    <div className="space-y-4">
+      <Alert type="error" message={error} />
+      <div className="flex justify-end"><Button variant="secondary" onClick={onClose}>Close</Button></div>
+    </div>
+  );
+
+  const selectCls = 'w-full border border-gray-200 rounded px-2 py-1.5 text-sm bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400';
+
+  return (
+    <div className="space-y-4">
+      <p className="text-sm text-gray-500">
+        One value per subject over an X axis — each column is a subject, each row an X value. Blank where a subject has no value.
+      </p>
+
+      <div>
+        <label htmlFor="export-x" className="block text-xs font-medium text-gray-500 mb-1">X axis (rows)</label>
+        <select id="export-x" value={xField} onChange={(e) => setXField(e.target.value)} className={selectCls}>
+          {xOptions.map((o) => <option key={o.id} value={o.id}>{o.label}</option>)}
+        </select>
+      </div>
+
+      <div>
+        <label htmlFor="export-data" className="block text-xs font-medium text-gray-500 mb-1">Data (cells)</label>
+        <select id="export-data" value={effDataId ?? ''} onChange={(e) => setDataId(e.target.value)} className={selectCls}>
+          {groupedParams.map((g) => (
+            <optgroup key={g.group} label={PARAM_GROUP_LABELS[g.group] ?? g.group}>
+              {g.items.map((p) => <option key={p.id} value={p.id}>{p.label}</option>)}
+            </optgroup>
+          ))}
+        </select>
+      </div>
+
+      <div>
+        <label htmlFor="export-group" className="block text-xs font-medium text-gray-500 mb-1">Group by</label>
+        <select id="export-group" value={groupBy} onChange={(e) => setGroupBy(e.target.value)} className={selectCls}>
+          <option value="__none__">— None —</option>
+          <option value="__name__">Name</option>
+          <option value="__id__">Subject ID</option>
+          {subjectTemplate.filter((f) => f.active).map((f) => (
+            <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+          ))}
+        </select>
+      </div>
+
+      <p className="text-xs text-gray-400">
+        {hasData
+          ? `${matrix.rows.length} row${matrix.rows.length !== 1 ? 's' : ''} × ${matrix.columns.length} subject${matrix.columns.length !== 1 ? 's' : ''}`
+          : 'No data for this selection yet.'}
+      </p>
+
+      <div className="flex justify-end gap-2 pt-2">
+        <Button variant="secondary" onClick={onClose}>Cancel</Button>
+        <Button onClick={handleExport} disabled={!hasData}>Export CSV</Button>
+      </div>
+    </div>
+  );
+}
+```
+
+- [ ] **Step 4: Run the test to verify it passes**
+
+Run: `npx jest tests/ExportDataModal.test.jsx`
+Expected: PASS (all four cases).
+
+- [ ] **Step 5: Run the full suite**
+
+Run: `npm test`
+Expected: `dataExport` + `ExportDataModal` green; only the two known pre-existing suites fail; no new failures.
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add frontend/src/components/ExportDataModal.jsx frontend/tests/ExportDataModal.test.jsx
+git commit -m "feat(export): modal becomes X / Data / Group by pickers, subjects as columns"
+```
+
+---
+
+### Task 4: Remove the dead assignable-axes code
+
+**Files:**
+- Modify: `frontend/src/lib/dataExport.js` (delete unused exports)
+- Test: `frontend/tests/dataExport.test.js` (delete their describe blocks + imports)
+
+**Interfaces:**
+- Removes (now unused after Task 3): `EXPORT_DIMENSIONS`, `dimLabel`, `otherDimension`, `listDateMembers`, `buildStatusIndex`, `listParameterMembers`, `listDimensionMembers`, and `buildMatrix`.
+- Keeps: `extractValue`, `listExportableParams`, `subjectGroupValue`, `listSubjectMembers`, `numericFieldVal`, `listSampleMembers`, `buildSampleIndex`, `buildSubjectSeriesMatrix`, `toCSV`, `csvFilename`, and the private `hasValue`, `dateKey`, `escapeCsvCell`, `xFieldLabel`.
+
+- [ ] **Step 1: Delete the dead source exports**
+
+In `frontend/src/lib/dataExport.js`, delete these eight exported definitions entirely (they are only used by each other and the old modal, now replaced): `EXPORT_DIMENSIONS`, `dimLabel`, `otherDimension`, `listDateMembers`, `buildStatusIndex`, `listParameterMembers`, `listDimensionMembers`, `buildMatrix`. Also update the top-of-file comment to describe the subject-series export (drop the "dimension-agnostic buildMatrix" wording). Keep `dateKey`, `hasValue`, `escapeCsvCell`, and everything listed under "Keeps" above.
+
+- [ ] **Step 2: Delete their tests**
+
+In `frontend/tests/dataExport.test.js`, delete the describe blocks and their now-unused import identifiers for the removed functions: the `describe('dimension primitives', …)`, `describe('subjectGroupValue', …)` KEEP (subjectGroupValue is kept — do NOT delete it), `describe('listDateMembers', …)`, `describe('buildStatusIndex', …)`, `describe('listParameterMembers / listDimensionMembers', …)`, and `describe('buildMatrix', …)` blocks. Remove `EXPORT_DIMENSIONS`, `dimLabel`, `otherDimension`, `listDateMembers`, `buildStatusIndex`, `listDimensionMembers`, `listParameterMembers`, and `buildMatrix` from the file's `import` statements, leaving the imports for kept functions (`extractValue`, `listExportableParams`, `subjectGroupValue`, `listSubjectMembers`, `numericFieldVal`, `listSampleMembers`, `buildSampleIndex`, `buildSubjectSeriesMatrix`, `toCSV`, `csvFilename`).
+
+- [ ] **Step 3: Verify nothing references the removed names**
+
+Run: `grep -rnE "buildMatrix|EXPORT_DIMENSIONS|listDimensionMembers|buildStatusIndex|listDateMembers|listParameterMembers|otherDimension|dimLabel" frontend/src frontend/tests`
+Expected: no output (all references gone).
+
+- [ ] **Step 4: Run the suites**
+
+Run: `npx jest tests/dataExport.test.js tests/ExportDataModal.test.jsx`
+Expected: PASS. Then `npm test` — only the two known pre-existing suites fail, no new failures.
+
+- [ ] **Step 5: Commit**
+
+```bash
+git add frontend/src/lib/dataExport.js frontend/tests/dataExport.test.js
+git commit -m "refactor(export): remove dead assignable-axes helpers and their tests"
+```
+
+---
+
+## Self-Review Notes
+
+- **Spec coverage:** three pickers (Task 3) · X = Date/# Days Reach/daily field with the exact semantics (Tasks 1–2) · subjects always columns, clustered by group, blank rows dropped (Task 2) · Group by validated/defaulted (Task 3) · CSV `Data,<metric>` + group row + X-corner (Tasks 2–3, reusing `toCSV`) · assignable-axes UI/machinery removed (Tasks 3–4). All covered.
+- **Type consistency:** sample member `{ id, label, sampleValue }`, subject column `{ id, label, animalId, group }`, and matrix `{ context, corner, groupAxis, columns, rows }` are used identically across Tasks 1–3 and match the existing `toCSV`.
+- **Out of scope (per spec):** assignable columns/pinned, subject subsetting, analyzed-only day counting, footer/repeat line.

docs/superpowers/specs/2026-05-01-numerical-csv-buckets-design.md

@@ -0,0 +1,235 @@
+# Numerical CSV-analysis buckets, persisted per animal
+
+**Date:** 2026-05-01
+**Scope:** `frontend/src/components/CsvAnalysis.jsx`, `frontend/src/lib/csvAnalysis.js`, `frontend/src/api/client.js`, `frontend/src/pages/DailyStatusDetail.jsx`, `backend/prisma/schema.prisma`, backend animal route.
+
+## Goal
+
+In the daily-status CSV-analysis flow, let the user define an extra type of bucket — a **numerical** bucket — alongside the existing note-classification buckets (Success / Failure / Other / custom). A numerical bucket plots its assigned notes' numeric portion against the CSV frame column (or timestamp as fallback) and reports an average. The bucket structure and per-bucket note assignments persist on the `Animal` so subsequent CSV uploads for the same subject don't need to be re-classified from scratch.
+
+## Section 0 — Preconditions
+
+Before applying the schema migration, back up the live Postgres database to a sibling `archived/` folder.
+
+```bash
+mkdir -p /home/sam/docker-images/archived
+docker exec experiments_postgres pg_dump -U expuser -d experiments_db -F c \
+  > /home/sam/docker-images/archived/experiments_db_$(date +%Y%m%d_%H%M%S).dump
+```
+
+- Verify the dump file size is greater than 0 bytes before proceeding.
+- Restore command (if needed):
+  ```bash
+  docker exec -i experiments_postgres pg_restore -U expuser -d experiments_db -c \
+    < /home/sam/docker-images/archived/<dumpfile>
+  ```
+
+## Section 1 — Data model
+
+### Schema change
+
+Add one nullable JSON column to `Animal`:
+
+```prisma
+model Animal {
+  id                   String        @id @default(uuid())
+  experiment_id        String
+  animal_id_string     String
+  animal_name          String
+  subject_info         Json?
+  csv_analysis_config  Json?         // <— new
+  experiment           Experiment    @relation(fields: [experiment_id], references: [id], onDelete: Cascade)
+  daily_statuses       DailyStatus[]
+
+  @@map("animals")
+}
+```
+
+### Stored shape
+
+```jsonc
+{
+  "buckets": [
+    { "name": "Success",      "type": "note",      "notes": ["S", "S1"] },
+    { "name": "Failure",      "type": "note",      "notes": ["F"] },
+    { "name": "Other",        "type": "note",      "notes": [] },
+    { "name": "Lick latency", "type": "numerical", "notes": ["L25", "L30"] }
+  ]
+}
+```
+
+### Rules
+
+- `type: "note"` — existing behavior (counted, run-length-encoded, contributes to daily-status summary).
+- `type: "numerical"` — plotted vs. frame (or timestamp); reports average; **excluded** from category counts, consecutive runs, and the "Save metrics to daily status" calculation.
+- The three default note buckets (Success, Failure, Other) are always present: seeded into `buckets` on first save and undeletable in the UI.
+- Custom buckets (both note and numerical) can be removed via an `✕` control on the bucket. Removal puts any notes that were assigned to that bucket back into Unassigned for the current session and drops the bucket from `buckets[]` on next save.
+- `notes` arrays persist as raw trimmed strings. A new CSV upload looks up each unique note in the persisted `notes` arrays to auto-classify; any leftover notes appear as **Unassigned**.
+- A single note value belongs to at most one bucket. Assigning a note to bucket B removes it from any other bucket's `notes[]` first.
+- Bucket names are unique within `buckets`. Renaming is out of scope for v1.
+- `csv_analysis_config` may be `null` (animal never had CSV analysis run); UI falls back to `DEFAULT_BUCKETS` in that case.
+
+### Backend API
+
+- `GET /api/animals/:id` — already returns the full animal row. `csv_analysis_config` is included automatically.
+- `PATCH /api/animals/:id/csv-config` — body `{ buckets: [...] }`. Validates:
+  - `buckets` is an array.
+  - Each entry has non-empty trimmed `name`, `type ∈ {"note","numerical"}`, `notes` is `string[]`.
+  - `name` values are unique within the array.
+  - The three default note buckets (Success/Failure/Other) are present.
+  Replaces the column atomically. Returns updated animal. Audit-logged via existing middleware.
+
+## Section 2 — Frontend changes
+
+### `CsvAnalysis.jsx` (the main refactor)
+
+1. **New prop `animal`** — passed from `DailyStatusDetail`. Used to read & write `csv_analysis_config`.
+
+2. **State refactor**: replace the parallel `categories: string[]` + `customCategories: string[]` + `classifications: { [note]: category }` with a single source of truth:
+   ```js
+   const [buckets, setBuckets] = useState([]);
+   // bucket: { name: string, type: 'note' | 'numerical', notes: string[] }
+   ```
+   Derive `classifications`, `categories`, `customCategories` from `buckets` for compatibility with downstream code (`runAnalysis`, color helpers).
+
+3. **Seeding on entering classify phase**:
+   - If `animal.csv_analysis_config?.buckets` exists, use it.
+   - Otherwise initialize from `DEFAULT_BUCKETS` (Success/Failure/Other, all `type: "note"`, empty `notes`).
+   - Auto-classify: any `uniqueNote` whose value appears in some bucket's `notes[]` is considered already-assigned and does not appear in Unassigned.
+
+4. **"+ Add field" button** (replaces today's "+ New category"):
+   - Inline form: `<input name>` + radio toggle `( ) Note  ( ) Numerical`.
+   - On submit, appends `{ name, type, notes: [] }` to `buckets`.
+
+5. **`CategoryBucket` extension**:
+   - Accepts `type` prop.
+   - Color allocation: `getCategoryColors` is updated to take the full bucket list and assign `EXTRA_COLORS` round-robin across all custom buckets (note + numerical combined), so adding numerical buckets does not shift the colors of existing note buckets.
+   - Numerical buckets render with a "numerical" header badge to distinguish them visually.
+   - Numerical buckets show an "**Add all unassigned**" button that bulk-moves every currently-unassigned unique note into this bucket's `notes[]`.
+   - Custom buckets (note or numerical) show an `✕` remove control on hover.
+   - In results phase, numerical buckets show a footer line: `Avg: 24.3  ·  47/50 rows plottable`.
+
+6. **`compute()`**:
+   - Note-type buckets: pass through `runAnalysis(rows, timestampCol, noteCol, classifications)` as today, but `classifications` is built only from `note`-type buckets (numerical-bucket assignments are excluded so they don't pollute counts/runs).
+   - Numerical-type buckets: for each, call new helper `computeNumericSeries(rows, frameCol || timestampCol, noteCol, bucket)` returning `{ points: [{x, value, raw}], avg, skipped, total, xLabel }`.
+   - After successful analysis, call `animalsApi.updateCsvConfig(animal.id, { buckets })`. Failure surfaces a non-blocking toast/inline error; analysis results still render.
+
+7. **Results phase additions**:
+   - Existing tables (Category Counts, Consecutive Runs) iterate `buckets.filter(b => b.type === 'note')` — numerical buckets are excluded.
+   - New "Numerical Plots" section after `RunSequenceView`. One panel per numerical bucket, containing:
+     - Bucket name, average, skipped-count.
+     - Recharts `<LineChart>` with `XAxis dataKey="x"` (label = `xLabel`) and a single `<Line dataKey="value">`. Color from `getCategoryColors(bucket.name, customCategories)`.
+   - If a numerical bucket has zero plottable rows, render `"No plottable values — N of N note rows had no extractable number."` instead of a chart.
+
+### `frontend/src/lib/csvAnalysis.js`
+
+```js
+// Extract first signed decimal from a string. Returns null if none found.
+export function extractNumber(str) {
+  if (str == null) return null;
+  const m = String(str).match(/-?\d+(\.\d+)?/);
+  return m ? parseFloat(m[0]) : null;
+}
+
+// Build a numerical series for one bucket.
+// xColName: frameCol if set, else timestampCol. xLabel reflects which.
+export function computeNumericSeries(rows, xColName, noteCol, bucket) {
+  const noteSet = new Set(bucket.notes);
+  const points = [];
+  let skipped = 0;
+  let total = 0;
+
+  for (const r of rows) {
+    const note = String(r[noteCol] ?? '').trim();
+    if (!noteSet.has(note)) continue;
+    total++;
+    const value = extractNumber(note);
+    const x = parseFloat(r[xColName]);
+    if (value == null || Number.isNaN(x)) { skipped++; continue; }
+    points.push({ x, value, raw: note });
+  }
+
+  points.sort((a, b) => a.x - b.x);
+  const avg = points.length === 0
+    ? null
+    : points.reduce((s, p) => s + p.value, 0) / points.length;
+
+  return { points, avg, skipped, total, xLabel: xColName };
+}
+```
+
+### `frontend/src/api/client.js`
+
+Add to `animalsApi`:
+```js
+updateCsvConfig: (animalId, config) =>
+  request(`/animals/${animalId}/csv-config`, { method: 'PATCH', body: JSON.stringify(config) }),
+```
+
+### `frontend/src/pages/DailyStatusDetail.jsx`
+
+Single change: pass `animal={status.animal}` to `<CsvAnalysis>`.
+
+## Section 3 — Behavior details
+
+- **Frame column** stays optional. If unset when running analysis with ≥1 numerical bucket, x-axis falls back to `timestampCol`. Chart axis label and the panel header reflect which axis is in use.
+- **Letter stripping** uses `/-?\d+(\.\d+)?/` (first signed decimal in the string). Notes with no extractable number are counted as `skipped`.
+- **Persistence trigger**: config is saved after `compute()` succeeds. Editing buckets in classify phase without running analysis does not persist.
+- **Multiple numerical buckets**: fully supported. Each gets its own chart and its own average.
+- **Same note in multiple buckets**: prevented at the UI level — assigning a note to a bucket removes it from any other bucket. Backend does not enforce this (UI invariant).
+
+## Section 4 — Error handling
+
+| Failure                                       | Behavior                                                                                  |
+|-----------------------------------------------|-------------------------------------------------------------------------------------------|
+| Save config (PATCH) fails                     | Local state unchanged; non-blocking inline error in classify/results UI; analysis still renders. |
+| Numerical bucket has zero plottable rows      | Panel shows "No plottable values — N of N rows had no extractable number." No crash.      |
+| Frame column absent + numerical bucket exists | Falls back to timestamp; chart axis label reflects this.                                  |
+| Migration                                     | Run the Section 0 backup first; abort if dump file size is 0 bytes.                       |
+| Validation rejection on PATCH                 | UI shows server error message; user can re-edit and retry.                                |
+
+## Section 5 — Testing
+
+### Frontend unit (Vitest, `frontend/src/lib/`)
+
+- `extractNumber()`:
+  - `"L25.5"` → 25.5
+  - `"R-12"` → -12
+  - `"trial_007"` → 7
+  - `"3.2e2"` → 3.2 (loses scientific notation — accepted limitation)
+  - `"42 ms"` → 42
+  - `"abc"` → null
+  - `""` → null
+  - `null` → null
+- `computeNumericSeries()`:
+  - All rows valid → correct points + average + skipped=0
+  - Some unparseable → correct skipped count, points exclude bad rows
+  - All unparseable → empty points, avg=null, skipped=total
+  - `xColName` missing from rows → all skipped (NaN x)
+  - Bucket with empty `notes[]` → empty points, total=0
+  - Output sorted ascending by x
+
+### Backend unit
+
+- `PATCH /animals/:id/csv-config`:
+  - Valid body → 200, persisted, audit log row written
+  - Empty bucket name → 400
+  - Duplicate names → 400
+  - Invalid `type` value → 400
+  - `notes` not an array → 400
+  - Missing default bucket (e.g. no "Success") → 400
+
+### Integration / manual
+
+- Upload a CSV → create one numerical bucket → assign notes → run analysis → reload page → upload same CSV → confirm bucket is pre-populated and assignments are restored.
+- Same flow with a CSV containing genuinely-new note values → confirm new notes show as Unassigned, old ones do not.
+- Numerical bucket with frame col present → chart x-axis labeled with frame col name.
+- Numerical bucket with frame col cleared → chart x-axis labeled with timestamp col name.
+
+## Section 6 — Out of scope (v1)
+
+- Bucket renaming after creation.
+- Y-axis range customization, multi-line overlays.
+- Showing the chart for past `DailyAnalysis` records (frame data isn't stored; user re-drops the CSV to plot).
+- Per-experiment defaults (config is per-animal only).
+- Editing config from a settings page; config is only edited via the CSV-analysis flow.

docs/superpowers/specs/2026-06-01-cross-subject-plot-interactions-design.md

@@ -0,0 +1,113 @@
+# Cross-subject metrics plot — interaction enhancements
+
+**Date:** 2026-06-01
+**Component:** `frontend/src/components/AnalysisCharts.jsx` → `ExperimentAnalysisCharts`
+**Rendered on:** `frontend/src/pages/ExperimentDetail.jsx`
+
+## Summary
+
+Add four client-side interaction features to the "Cross-subject metrics" plot (two
+Recharts `LineChart`s — count-per-session and success-rate — where each line is one
+subject, colored by group):
+
+1. A toggleable sidebar listing subjects grouped by their group, with per-subject and
+   per-group checkboxes to show/hide each subject's line.
+2. Clicking a subject's legend entry toggles that subject's line visibility.
+3. The hover tooltip orders its rows to match the vertical stacking of the points
+   (highest value at top).
+4. Hovering a subject's legend entry (or sidebar row) highlights that subject's line.
+
+## Constraints
+
+- **Frontend only.** No backend, API, or database changes. All state is client-side
+  React state, not persisted.
+- **No regressions.** The existing global controls (X axis, Color by, tick step), the
+  per-chart customize bars (size, Y range, X zoom, per-chart X-field override), the
+  Y-metric selector, and the sibling `SubjectAnalysisCharts` component are untouched.
+- Scope is limited to `ExperimentAnalysisCharts`.
+
+## Visibility model (decided)
+
+Visibility is **global per-subject**: toggling a subject anywhere — sidebar checkbox,
+either chart's legend — hides or shows it in **both** charts simultaneously. "Per plot"
+in the original request resolves to per-subject, not per-chart.
+
+## Shared state (lifted into `ExperimentAnalysisCharts`)
+
+- `hiddenSubjects: Set<animalId>` — empty = all visible. Global across both charts.
+  Stale ids (subject removed) are harmless: they match no line.
+- `highlightedSubject: animalId | null` — transient hover state, shared by both charts
+  and the sidebar.
+- `sidebarOpen: boolean` — default `false`.
+
+Helpers: `toggleHidden(id)`, `setGroupHidden(groupSubjectIds, hidden)`, `showAll()`,
+`setHighlight(id | null)`.
+
+## Layout
+
+A toggle button (`▸ Subjects`) is added to the existing global-controls row. When open,
+the card body becomes a flex row:
+
+- Charts area: `flex-1`; the existing `ResponsiveContainer width="100%"` re-flows the
+  charts narrower automatically.
+- Sidebar panel: ~210px fixed width, `border-l`, top-aligned with the card.
+
+```
+┌─ Cross-subject metrics ─────────  X axis▾  Color by▾  Tick  [▸ Subjects] ─┐
+│                                                 │  SUBJECTS        Show all │
+│   ┌──────────────────────────────┐             │ ┌───────────────────────┐ │
+│   │   Count chart (re-flows)      │             │ │ ▣ Group A          (3)│ │
+│   └──────────────────────────────┘             │ │   ☑ ● Mouse-A1        │ │
+│   ┌──────────────────────────────┐             │ │   ☑ ● Mouse-A2        │ │
+│   │   Success-rate chart          │             │ │   ☐ ● Mouse-A3        │ │
+│   └──────────────────────────────┘             │ │ ▢ Group B          (2)│ │
+│                                                 │ │   ☐ ● Mouse-B1        │ │
+│                                                 │ └───────────────────────┘ │
+└─────────────────────────────────────────────────────────────────────────────┘
+```
+
+### Sidebar contents
+
+- **Grouping** reuses the current `Color by` field via the existing `lines[].group`.
+  With `Color by = none`, all subjects fall under a single "—" group.
+- **Subject row**: checkbox (checked = visible) + color swatch (`lines[].color`) + name.
+  Hovering the row sets `highlightedSubject`.
+- **Group row**: tri-state checkbox — checked if all in group visible, empty if all
+  hidden, indeterminate if mixed. Clicking toggles the whole group. Shows group name +
+  count.
+- **"Show all"** header link — clears `hiddenSubjects`; shown only when something is
+  hidden.
+
+## Behavior details
+
+1. **Visibility** — every subject `<Line>` is rendered always (in both charts) with
+   `hide={hiddenSubjects.has(l.id)}` instead of filtering the `lines` array. Recharts
+   keeps a greyed, still-clickable legend entry for hidden lines and excludes them from
+   the tooltip payload automatically.
+
+2. **Legend click** — `<Legend onClick={(o) => toggleHidden(o.dataKey)} />` on both
+   charts. `dataKey` is `l.id` (lines use `dataKey={l.id} name={l.id}`).
+
+3. **Tooltip ordering** — the existing custom `ExpTooltip` sorts `payload` by `value`
+   descending before rendering its rows, so the topmost line is first. Null/hidden
+   subjects are already excluded. Applies to both the count and rate tooltips.
+
+4. **Legend hover highlight** — `<Legend onMouseEnter={(o) => setHighlight(o.dataKey)}
+   onMouseLeave={() => setHighlight(null)} />`. Each line's `strokeWidth` is `3.5` when
+   `highlightedSubject === l.id`, else `2` (other lines unchanged — "thicken hovered
+   only"). Highlight applies in **both** charts and is also driven by sidebar-row hover.
+
+## Testing
+
+- Manual verification in the running app (`ExperimentDetail` page with an experiment
+  that has animals and saved analysis metrics):
+  - Open/close sidebar; charts re-flow.
+  - Toggle a subject checkbox → line disappears in both charts; legend entry greys out.
+  - Group checkbox toggles all members; shows indeterminate when mixed.
+  - "Show all" clears hidden state.
+  - Click a legend entry → toggles in both charts.
+  - Hover tooltip rows are ordered highest-value-first.
+  - Hover a legend entry / sidebar row → that line thickens in both charts.
+- Confirm existing controls (X axis, Color by, tick step, per-chart customize, Y-metric)
+  still work.
+```

docs/superpowers/specs/2026-06-01-persist-cross-subject-plot-config-design.md

@@ -0,0 +1,137 @@
+# Persist cross-subject plot display settings per experiment
+
+**Date:** 2026-06-01
+**Backend:** `backend/src/routes/experiments.js`, Prisma schema + migration
+**Frontend:** `frontend/src/components/AnalysisCharts.jsx` (`ExperimentAnalysisCharts`), `frontend/src/pages/ExperimentDetail.jsx`, `frontend/src/api/client.js`, `frontend/src/lib/crossSubjectChart.js`
+
+## Summary
+
+Persist a user's display settings for the "Cross-subject metrics" plot per experiment, so they are restored on the next visit instead of being re-applied every time. The settings live in a new nullable JSONB column on `experiments`, are saved via a dedicated auto-saving (debounced) endpoint, and hydrate the chart on load.
+
+## Decisions (from brainstorming)
+
+- **Scope:** the cross-subject plot only (the per-experiment chart in `ExperimentAnalysisCharts`). The sibling `SubjectAnalysisCharts` (per-animal page) is out of scope.
+- **Save trigger:** auto-save, debounced ~1s after the last change. No explicit save button.
+- **Storage:** Postgres via Prisma (the project's DB; it is not SQLite), following the existing `template` / `subject_info_template` / `csv_analysis_config` JSONB pattern.
+
+## Persisted config shape
+
+`experiments.plot_config` (JSONB, nullable). `null` = nothing saved → chart uses computed defaults.
+
+```jsonc
+{
+  "xField":   "<fieldId|'__days__'>",
+  "groupBy":  "<fieldId|''>",
+  "tickStep": 1,
+  "metric":   "total|Success|Failure",
+  "hiddenSubjects": ["<animalId>", ...],
+  "sidebarOpen": false,
+  "counts": { "height": 200, "yMin": "", "yMax": "", "xZoomMin": "", "xZoomMax": "", "xFieldOverride": null },
+  "rate":   { "height": 160, "yMin": "", "yMax": "", "xZoomMin": "", "xZoomMax": "", "xFieldOverride": null }
+}
+```
+
+All keys are optional on read — unknown/missing keys fall back to defaults, so older blobs and future additions both stay safe. `highlightedSubject` is transient and is NOT persisted.
+
+## Backend
+
+### Migration (additive, safe)
+
+`backend/prisma/migrations/<ts>_add_experiment_plot_config/migration.sql`:
+```sql
+ALTER TABLE "experiments" ADD COLUMN "plot_config" JSONB;
+```
+Schema: add `plot_config Json?` to `model Experiment`. Existing rows get `NULL`; nothing else changes.
+
+### Route: `PUT /api/experiments/:id/plot-config`
+
+Mirrors the existing `PUT /:id/subject-template` handler, with two differences: **no audit-log write** (debounced auto-save would spam `audit_logs`; this is a UI preference, not experiment data), and a different validator.
+
+```js
+// PUT /api/experiments/:id/plot-config — persist UI display settings (no audit log)
+router.put('/:id/plot-config', async (req, res, next) => {
+  try {
+    const experiment = await prisma.experiment.findUnique({ where: { id: req.params.id } });
+    if (!experiment) return res.status(404).json({ error: 'Experiment not found' });
+
+    const config = req.body;
+    const validationError = validatePlotConfig(config);
+    if (validationError) return res.status(422).json({ error: validationError });
+
+    await prisma.experiment.update({
+      where: { id: req.params.id },
+      data: { plot_config: config },
+    });
+    res.json(config);
+  } catch (err) { next(err); }
+});
+```
+
+`validatePlotConfig(config)`:
+- Must be a non-null, non-array plain object → else `'plot_config must be an object'`.
+- Serialized size cap: `JSON.stringify(config).length <= 16384` → else `'plot_config too large'`.
+- If `hiddenSubjects` present, must be an array of strings with length ≤ 500 → else `'hiddenSubjects invalid'`.
+- Otherwise permissive (stores the object as-is). Keeps the backend agnostic to the exact UI shape.
+
+### Read path
+
+`GET /api/experiments/:id` already returns all scalar columns (it uses `findUnique` without a `select`), so `plot_config` rides along automatically. No new GET endpoint.
+
+## Frontend
+
+### API client (`frontend/src/api/client.js`)
+
+Add to `experimentsApi`:
+```js
+savePlotConfig: (id, config) => api.put(`/experiments/${id}/plot-config`, config).then((r) => r.data),
+```
+
+### Pure helpers (`frontend/src/lib/crossSubjectChart.js`)
+
+Two pure, unit-tested functions isolate (de)serialization from React:
+
+- `serializePlotConfig({ xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen, counts, rate })` → plain JSON object (turns the `hiddenSubjects` Set into a sorted array; copies the two per-chart snapshots).
+- `readPlotConfig(raw)` → normalized `{ xField?, groupBy?, tickStep?, metric?, hiddenSubjects: string[], sidebarOpen: bool, counts: {...}, rate: {...} }` with defensive defaults for `null`/malformed input (never throws).
+
+### `useChartSettings` refactor (`AnalysisCharts.jsx`)
+
+- Add optional `initial` argument; seed `height`, `yMin`, `yMax`, `xZoomMin`, `xZoomMax`, `xFieldOverride` from it when provided.
+- Expose a `snapshot` object (those serializable values) for the parent to persist.
+- `reset()` and `isDirty` keep working. `SubjectAnalysisCharts` calls the hook with no `initial`, so its behavior is unchanged.
+
+### `ExperimentAnalysisCharts` wiring
+
+New props: `plotConfig` (raw from `experiment.plot_config`) and `onPersistConfig(config)`.
+
+- **Hydrate once:** read `readPlotConfig(plotConfig)` into a memo; pass `counts`/`rate` slices as `initial` to the two `useChartSettings` calls; in a one-time effect (guarded by `hydratedRef`) seed `xField`, `groupBy`, `tickStep`, `metric`, `hiddenSubjects` (`new Set(cfg.hiddenSubjects)`), `sidebarOpen`.
+- **Serialize:** `const currentConfig = useMemo(() => serializePlotConfig({...all state, counts: countsS.snapshot, rate: rateS.snapshot}), [deps])`.
+- **Debounced save:** an effect keyed on `JSON.stringify(currentConfig)` that, *after* hydration and only when the value differs from `lastSavedRef.current`, sets a 1s timeout calling `onPersistConfig(currentConfig)`, then updates `lastSavedRef`. Clears the timeout on change/unmount. This prevents both a save-on-load loop and no-op writes.
+- **Status hint:** a tiny "Saving…/Saved ✓" indicator near the controls; on save failure show a quiet "couldn't save layout" note and leave the chart fully functional.
+
+### `ExperimentDetail.jsx`
+
+Pass the two props:
+```jsx
+<ExperimentAnalysisCharts
+  animals={animals}
+  experimentStatuses={experimentStatuses}
+  subjectTemplate={subjectTemplate}
+  dailyTemplate={dailyTemplate}
+  plotConfig={experiment.plot_config}
+  onPersistConfig={(cfg) => experimentsApi.savePlotConfig(id, cfg)}
+/>
+```
+
+## Edge cases & non-goals
+
+- **Stale subject ids:** a hidden `animalId` for a since-removed animal simply matches no line (already how visibility behaves). No cleanup.
+- **Single-tenant, last-write-wins:** no per-user configs (there is no auth layer); config is shared per experiment.
+- **Failure is non-fatal:** a failed save never breaks the chart; the user just sees the quiet note and can retry by changing something.
+- **Untouched:** template/subject-template routes and their audit logging; `SubjectAnalysisCharts`; the cross-subject interaction behaviors shipped previously.
+
+## Testing
+
+- **Pure helpers (Jest, `frontend/tests/crossSubjectChart.test.js`):** `serializePlotConfig` round-trips (Set→sorted array, includes per-chart snapshots); `readPlotConfig` returns defaults for `null`/`{}`/malformed input and preserves valid fields. Never throws.
+- **Backend route (Jest + supertest + mocked Prisma, `backend/tests/experiments.test.js`):** `PUT /:id/plot-config` returns 200 and calls `prisma.experiment.update` with the config for a valid body; 404 when the experiment is missing; 422 for a non-object body, an oversized body, and an invalid `hiddenSubjects`; and does NOT call `prisma.auditLog.create`.
+- **Frontend smoke (Jest + RTL, mocked recharts, `frontend/tests/ExperimentAnalysisCharts.test.jsx`):** hydrates state from a `plotConfig` prop (e.g. a hidden subject starts unchecked); and, with fake timers, calls `onPersistConfig` ~1s after a change but not on initial render.
+- **Manual:** adjust the plot on one experiment, reload → settings persist; open a second experiment → independent config; confirm no new `audit_logs` rows from plot tweaks.

docs/superpowers/specs/2026-07-06-experiment-data-export-design.md

@@ -0,0 +1,148 @@
+# Experiment Data Export (CSV) — Design
+
+**Date:** 2026-07-06
+**Status:** Approved, ready for implementation plan
+
+## Goal
+
+Let a user on the experiment page export a chosen daily parameter as a CSV
+file shaped as a matrix: **each row is a date, each column is a subject**, each
+cell is that subject's value for the parameter on that date. Every daily
+parameter must be exportable, including the session metrics derived from
+`analysis_summary`.
+
+## Scope
+
+- **In:** CSV export, one parameter per file, client-side generation, a picker
+  UI on the experiment page.
+- **Out (deferred):** true `.xlsx` output (would add a client-side library such
+  as SheetJS later; the pure helpers stay format-agnostic so the workbook
+  builder can be added without reshaping the data), multi-parameter / multi-sheet
+  export, a backend export endpoint.
+
+## Approach
+
+Fully client-side. The existing `GET /api/experiments/:id/daily-statuses`
+endpoint already returns every field required per status — builtin fields
+(`experiment_description`, `vitals`, `treatment`, `notes`), `custom_fields`, and
+`analysis_summary`. The experiment page currently fetches only the
+`analysisOnly=true` subset (for charts); the export modal fetches the **full**
+set on open, pivots it into a date×subject matrix in the browser, serializes to
+CSV, and triggers a download. No backend change.
+
+Rejected alternative: a backend `/export` route streaming CSV. It only pays off
+for very large datasets or server-side xlsx, at the cost of a new route, tests,
+and duplicating the template/parameter logic on the server. Research datasets
+here are small (tens of subjects, hundreds of dates), so client-side is simpler
+and unit-testable.
+
+## Exportable parameters
+
+The picker is grouped into two sections.
+
+### Session metrics (from `analysis_summary`)
+
+- **Total attempts** → `analysis_summary.total`
+- **Success rate** → `analysis_summary.success_rate`, exported as the **raw
+  0–1 fraction** (not multiplied to a percentage)
+- One entry per **dynamic count category** found in the data →
+  `analysis_summary.counts[category]`. Categories are enumerated by scanning the
+  fetched statuses (e.g. `Success`, `Failure`, `Other`, and any others present).
+
+### Daily record fields (from the daily template)
+
+- **Every** field defined in the daily template, including ones currently
+  hidden/inactive, since historical data may exist for them.
+- Builtin fields read from `status[field.key]`; custom fields read from
+  `status.custom_fields[field.fieldId]` (same accessor logic as
+  `AnalysisCharts.numericFieldVal`).
+- Values export as-is: text fields (e.g. `notes`, `vitals`) as strings, numeric
+  fields as numbers. No numeric coercion is required for export.
+
+## Matrix shape
+
+- **Rows** = every date that has at least one value for the chosen parameter
+  across any subject, sorted ascending, formatted `YYYY-MM-DD`. The first column
+  header is `Date`.
+- **Columns** = all enrolled animals, ordered by `animal_name`. A subject is a
+  column even if it has no value for the parameter (blank cells). On duplicate
+  `animal_name`, disambiguate the header with the subject's `animal_id_string`
+  (e.g. `Rat A (R-001)`).
+- **Cell** = the subject's value for the parameter on that date. Assumes one
+  daily status per (subject, date); if duplicates are ever present, the first in
+  date-ascending order wins.
+- Empty result (no dates have any value) is surfaced in the UI as a disabled
+  export / "no data for this parameter" note rather than producing an empty file.
+
+## Components
+
+### `frontend/src/lib/dataExport.js` (new, pure — no React, no I/O)
+
+Mirrors the existing `frontend/src/lib/crossSubjectChart.js` pure-helper pattern.
+
+- `listExportableParams(dailyTemplate, statuses)` → grouped, ordered parameter
+  descriptors. Each descriptor carries an id, label, group (`'metrics'` |
+  `'daily'`), and enough info to extract a value from a status. Session-metric
+  categories are derived from `statuses`; template params from `dailyTemplate`.
+- `extractValue(status, param)` → the raw cell value for one status/param (or
+  `null`/blank when absent). Encapsulates the builtin-vs-custom and
+  `analysis_summary` accessor logic.
+- `buildMatrix(statuses, animals, param)` → `{ columns, rows }` where `columns`
+  are the ordered subject headers and `rows` are `{ date, values: [...] }`
+  aligned to `columns`, including blank cells; rows limited to dates with data.
+- `toCSV(matrix)` → CSV string. Escapes any field containing a comma, double
+  quote, or newline per RFC 4180 (wrap in quotes, double embedded quotes).
+
+### `frontend/src/components/ExportDataModal.jsx` (new)
+
+- On open, fetches the full daily-statuses set via
+  `experimentsApi.getDailyStatuses(id, {})` (no `analysisOnly`).
+- Renders a grouped `<select>` of exportable parameters (Session metrics /
+  Daily record fields).
+- Shows a small summary line: "N dates × M subjects".
+- **Export CSV** button builds a `Blob`, creates an object URL, clicks a
+  temporary anchor, and revokes the URL. Filename:
+  `<sanitized-experiment-title>-<sanitized-param-label>.csv`.
+- Handles loading and error states for the fetch.
+
+### `frontend/src/pages/ExperimentDetail.jsx` (edit)
+
+- Add an **Export data** button in the header area (near **+ Add Animal**) that
+  opens `ExportDataModal`, passing the experiment id, title, `dailyTemplate`,
+  and `animals`.
+
+## Data flow
+
+1. User clicks **Export data** → modal opens.
+2. Modal fetches full statuses (all fields, all subjects).
+3. `listExportableParams(dailyTemplate, statuses)` builds the picker options.
+4. User selects a parameter → `buildMatrix(statuses, animals, param)` computes
+   the date×subject matrix; summary line updates.
+5. User clicks **Export CSV** → `toCSV(matrix)` → Blob download.
+
+## Error handling
+
+- Fetch failure: show an inline error in the modal; no download.
+- Parameter with no data across all subjects/dates: disable export and show a
+  brief note.
+- CSV correctness relies on `toCSV` escaping; covered by tests.
+
+## Testing
+
+Unit tests for `dataExport.js`, following `frontend/tests/crossSubjectChart.test.js`:
+
+- `listExportableParams`: includes all template fields (incl. inactive), the two
+  fixed session metrics, and each dynamic count category discovered in the data;
+  correct grouping/ordering.
+- `extractValue`: builtin vs custom field access; `total`, `success_rate` (raw
+  0–1), and `counts[category]`; missing values → blank/null.
+- `buildMatrix`: rows only for dates with data, ascending; all subjects as
+  columns with blanks; duplicate-name disambiguation; one-status-per-cell.
+- `toCSV`: escaping of commas, quotes, and newlines; header row; blank cells.
+
+## Out of scope / future
+
+- `.xlsx` output via a client-side workbook library (helpers already
+  format-agnostic).
+- Selecting multiple parameters (multi-sheet xlsx or multi-file/zip CSV).
+- Server-side export for very large datasets.

docs/superpowers/specs/2026-07-19-configurable-data-export-design.md

@@ -0,0 +1,101 @@
+# Configurable Data Export — Design
+
+**Date:** 2026-07-19
+**Status:** Approved (design)
+**Area:** `frontend/src/lib/dataExport.js`, `frontend/src/components/ExportDataModal.jsx`, `frontend/tests/dataExport.test.js`
+
+## Problem
+
+Today's data export has a fixed layout: each **row is a date**, each **column is a subject**, and the user picks **one parameter** whose value fills every cell (`buildMatrix` in `dataExport.js`). Users want to:
+
+1. Choose which dimension goes on rows and which on columns (fully assignable axes).
+2. See the pinned/third dimension labeled at the top of the file ("group information at the beginning").
+3. When Subject is an axis, see each subject's **group** in a separate cell, similar to the cross-subject metrics view.
+
+## Model: three interchangeable dimensions
+
+Export data spans three dimensions: **Date**, **Subject**, **Parameter**. A 2-D CSV grid can place two of them on the axes; the third must be **pinned** to a single value (a cell holds exactly one value).
+
+Each dimension yields an ordered list of **members**:
+
+- **Date** → sorted unique `YYYY-MM-DD` keys present in the data.
+- **Subject** → animals, headers disambiguated by `animal_id_string` on duplicate names (existing logic). When a group field is chosen, subjects are **clustered by group value, then sorted by name** within each group.
+- **Parameter** → `listExportableParams(dailyTemplate, statuses)` (session metrics, then daily fields — unchanged).
+
+Every cell is identified by a full `(dateKey, animalId, param)` triple: two coordinates come from the row/column members, the third from the pinned value. Lookup goes through a status index `Map(dateKey → Map(animalId → status))` (first-status-per-cell wins, as today), then `extractValue(status, param)`.
+
+Because Subject is always exactly one of the three dimensions (row, column, or pinned), the group annotation attaches to **at most one axis** — there is no 2-D corner-block complexity.
+
+## Modal UI (`ExportDataModal.jsx`)
+
+Replaces today's single "Parameter" dropdown with four controls:
+
+- **Rows** — Date / Subject / Parameter.
+- **Columns** — the two dimensions not chosen for Rows (auto-excludes the row pick; if a change collides, the other axis auto-shifts to a still-valid dimension).
+- **Fixed: `<leftover dim>`** — value dropdown for the auto-pinned third dimension. Its options are that dimension's members (a date, a subject, or a parameter, grouped like today for parameters).
+- **Group by** — subject_info fields plus "— None —". **Shown only when Subject is a row or column axis.** Defaults to the experiment's saved group field (`localStorage['exp-subject-group-<id>']`); falls back to None when unset or the field no longer exists.
+
+Live preview line stays: `N rows × M columns` (or "No data …" when empty). **Default state reproduces today's export exactly**: Rows = Date, Columns = Subject, Fixed = Parameter (first parameter). Export button disabled when the grid has no data rows.
+
+## CSV output format
+
+Structure: pinned-dimension context line, blank line, optional group row, header row, data rows.
+
+- **Line 1 (context):** two cells — the pinned dimension's label and its value, e.g. `Parameter,Total attempts` or `Subject,Mouse-01`. Beginning only (no footer).
+- **Blank line.**
+- **Grid**, with the group cell riding on whichever axis holds Subject.
+
+**Subject = columns** (e.g. Rows = Date, Fixed = Parameter) → extra **header row** labeled `Group`:
+
+```
+Parameter,Total attempts
+
+Group,Control,Control,Drug,Drug
+Date,Mouse-01,Mouse-02,Mouse-03,Mouse-04
+2026-01-01,12,10,8,9
+```
+
+**Subject = rows** (e.g. Cols = Parameter, Fixed = Date) → extra **leading column** labeled `Group`:
+
+```
+Date,2026-01-01
+
+Group,Subject,Total attempts,Success rate
+Control,Mouse-01,12,0.83
+Drug,Mouse-03,8,0.71
+```
+
+Rules:
+
+- The grid **corner label** is the row dimension's name (`Date`, `Subject`, or `Parameter`) — no longer hardcoded `Date`.
+- Missing group value → `—`. When **Group by = None**, the group row/column is omitted entirely.
+- **Empty-member rule:** Subject members are **always kept** (matches today's "keep all subject columns"). Date and Parameter members are **dropped when entirely blank** in the current grid.
+- Cell values use existing semantics: `0` / `''` are real; genuinely-missing lookups render as blank. CSV escaping via existing `escapeCsvCell`.
+
+## Refactor of `dataExport.js`
+
+Keep `extractValue` and `listExportableParams` unchanged. Replace single-purpose `buildMatrix` with dimension-agnostic pieces:
+
+- `listDateMembers(statuses)` → sorted unique dateKeys.
+- `listSubjectMembers(animals, groupField)` → `[{ id, header, group }]`, clustered by group then name; header disambiguation preserved.
+- `buildStatusIndex(statuses)` → `Map(dateKey → Map(animalId → status))`, first-wins.
+- `buildMatrix({ rowDim, colDim, pinnedDim, pinnedMember, groupField }, { statuses, animals, dailyTemplate })` → `{ context, groupAxis, corner, columns, rows }`. Resolves each cell's `(dateKey, animalId, param)` triple through the index + `extractValue`; applies the keep-subjects / drop-blank-date-and-param rule.
+- `toCSV(matrix)` → emits context line, blank line, optional group row, header row, data rows, with the dynamic corner label.
+- `csvFilename(title, pinnedMember.label)` → signature unchanged.
+
+## Testing (`tests/dataExport.test.js`)
+
+Existing `extractValue` / `listExportableParams` tests stay green. Add:
+
+- `listDateMembers`, `listSubjectMembers` (including group clustering + name tie-break + header disambiguation), `buildStatusIndex` (first-wins).
+- `buildMatrix` for all three axis pairings in both orientations.
+- Group row (Subject = columns) vs. group column (Subject = rows) placement; `—` fallback; Group = None omits it.
+- Empty-member rule: blank date/parameter members dropped, subjects retained.
+- `toCSV` snapshot including the context line and a group row.
+
+## Out of scope (YAGNI)
+
+- Stacking multiple values of the pinned dimension into one file (chose "pick one value").
+- Footer/repeat of the context line (beginning only).
+- Experiment-level metadata block (pinned dimension only).
+- Persisting axis choices across sessions (default reproduces current behavior; group field reuses existing saved value only).

docs/superpowers/specs/2026-07-19-subject-series-export-design.md

@@ -0,0 +1,86 @@
+# Subject-Series Data Export — Design
+
+**Date:** 2026-07-19
+**Status:** Approved (design)
+**Area:** `frontend/src/lib/dataExport.js`, `frontend/src/components/ExportDataModal.jsx`, `frontend/tests/`
+**Supersedes:** the assignable-axes UI from `2026-07-19-configurable-data-export-design.md` (that branch's `buildMatrix`/`toCSV`/subject-group work is reused; its rows/columns/pinned modal is replaced).
+
+## Problem
+
+The export modal currently offers assignable row/column/pinned axes. That is more than needed. The user wants the export to mirror the **cross-subject metrics plot**: pick an **X field** and a **data value**, with each **subject as a column series**, empty where a subject has no data point, plus each subject's **group** included. The one capability missing today is choosing the X (row) field — it is fixed to calendar Date, whereas the plot's X-axis offers **# Days Reach** and daily fields.
+
+## Layout (fixed)
+
+- **Columns = subjects**, one series per subject, ordered clustered-by-group then by name (existing `listSubjectMembers`).
+- **Rows = the chosen X field's values.**
+- **Cells = the chosen Data value** for that (subject, X); empty (`''`) when absent. `0` and `''` remain real values (existing `hasValue`/`extractValue`).
+- **Group row** gives each subject's group value (existing group-row support).
+
+There is no pinned dimension and no assignable columns.
+
+## The three pickers
+
+1. **X (rows).** Options: `Date`, `# Days Reach`, and each **active** daily-template field. Default `Date` (keeps the same date-rows × subject-columns grid as today; only the line-1 label changes to `Data`, see CSV output).
+2. **Data (cells).** Options: `listExportableParams(dailyTemplate, statuses)` — total, success rate, each count category, each daily field. Default: first parameter (`Total attempts`).
+3. **Group by.** Options: `— None —`, `Name`, `Subject ID`, and each active `subject_info` field. Defaults to the experiment's saved group field (`localStorage['exp-subject-group-<id>']`), validated against the available options and coerced to `__none__` when unset or stale. Always visible (subjects are always the columns).
+
+Preview line: `N rows × M subjects`. Export disabled when there are no data rows.
+
+## X-field semantics
+
+Each X coordinate maps a `(subject, X-value)` pair to a single daily status, from which the Data value is read:
+
+- **`Date`** → rows are the distinct calendar dates present (`YYYY-MM-DD`), sorted. Cell reads the subject's status on that date. (Today's behavior.)
+- **`# Days Reach`** → rows are `1, 2, 3, …` up to the maximum, per subject, of the count of that subject's recorded daily statuses. A cell for `(subject, N)` reads the subject's **Nth recorded day**, counting **all** recorded statuses sorted ascending by date (Day 1 = earliest record; days without an analysis summary are still counted — this intentionally differs from the plot, which counts analyzed sessions only).
+- **daily field** (e.g. `Weight (g)`) → rows are the distinct **numeric** values that field takes across the data (`numericFieldVal`: builtin via `status[field.key]`, custom via `status.custom_fields[field.fieldId]`, `parseFloat`, non-numeric → excluded), sorted ascending. A cell for `(subject, v)` reads that subject's status where the field equals `v`; on ties, first status by date wins.
+
+Row members that are entirely blank across all subjects are dropped (matching Date's existing behavior); subject columns are always kept even when empty.
+
+## CSV output
+
+Structure (X = # Days Reach, Data = Success rate, Group by = Treatment):
+
+```
+Data,Success rate
+Group,Control,Control,Drug
+# Days Reach,Mouse-A,Mouse-B,Mouse-C
+1,0.5,0.6,0.7
+2,0.55,,0.72
+3,0.6,0.65,
+```
+
+- **Line 1** names the Data metric so the file is self-describing: two cells, `Data` and the metric label.
+- **Blank line.**
+- **Group row** (`Group` + each subject's group), only when Group by ≠ None; missing group value → `—`.
+- **Header row:** the X-field label in the corner, then subject headers.
+- **Data rows:** the X value, then one cell per subject.
+
+LF line endings; every cell escaped via existing `escapeCsvCell`. Filename: existing `csvFilename(title, dataLabel)`.
+
+## Implementation notes
+
+Reuse from the current branch: `extractValue`, `listExportableParams`, `subjectGroupValue`, `listSubjectMembers`, `escapeCsvCell`, `toCSV` (its `{ context, corner, groupAxis, columns, rows }` shape is kept), and `csvFilename`.
+
+Replace: the general assignable-axes `buildMatrix(config, ctx)` and its members/dispatch helpers (`otherDimension`, `dimLabel`, `EXPORT_DIMENSIONS`, `listDateMembers`, `listDimensionMembers`, `listParameterMembers`, `buildStatusIndex` in its current form) — remove what the fixed layout no longer uses rather than leaving dead code.
+
+Add:
+- `numericFieldVal(status, field)` — mirror of the plot's helper (or import/share it).
+- `listSampleMembers(statuses, xField, dailyTemplate)` → the ordered row members for the chosen X coordinate (`{ id, label, ... }`).
+- `buildSampleIndex(statuses, xField, dailyTemplate)` → `Map(animalId → Map(sampleValue → status))`, first-status-per-cell wins, encoding the date/#days/field resolution above.
+- `buildSubjectSeriesMatrix({ xField, dataParam, groupField }, { statuses, animals, dailyTemplate })` → `{ context: { label: 'Data', value: dataParam.label }, corner: <X label>, groupAxis: grouping ? 'col' : null, columns: <subjects>, rows: [{ member, values }] }`, consumable by the existing `toCSV`.
+
+Simplify `ExportDataModal.jsx` to the three pickers over these helpers; drop the Rows/Columns/Fixed controls.
+
+## Testing
+
+- `listSampleMembers` / `buildSampleIndex` for each X coordinate: Date (unchanged), # Days Reach (all-records ordinal, per-subject alignment), daily field (distinct numeric values sorted, non-numeric dropped, tie first-by-date).
+- `buildSubjectSeriesMatrix`: subjects as columns clustered by group; empty cells where a subject lacks a point; blank row dropped; `groupAxis` null when Group by None.
+- `toCSV` reused; add/keep a snapshot for the new context line + group row.
+- `ExportDataModal`: renders three pickers; default X = Date produces date rows × subject columns with the chosen metric in cells; switching X to # Days Reach changes rows to ordinals; group row present when a valid group field is chosen; stale/unset group field coerces to None.
+
+## Out of scope (YAGNI)
+
+- Assignable columns / pinned dimension (removed).
+- Choosing a subset of subjects (all subjects always included).
+- Matching the plot's analyzed-only day counting (we count all recorded days).
+- A footer or repeated context line.

frontend/babel.config.js

@@ -0,0 +1,6 @@
+module.exports = {
+  presets: [
+    ['@babel/preset-env', { targets: { node: 'current' } }],
+    ['@babel/preset-react', { runtime: 'automatic' }],
+  ],
+};

frontend/e2e/app.spec.js

@@ -0,0 +1,105 @@
+// @ts-check
+const { test, expect } = require('@playwright/test');
+
+/**
+ * E2E tests run against the full Docker stack (frontend on port 52867,
+ * backend on port 3001). To run locally:
+ *   docker-compose up -d
+ *   npx playwright test
+ */
+
+const BASE_URL = process.env.E2E_BASE_URL || 'http://localhost:52867';
+
+test.describe('UI Flow — create experiment → add animal → log status', () => {
+  test('full happy path', async ({ page }) => {
+    await page.goto(BASE_URL);
+
+    // ── Create experiment ────────────────────────────────────────
+    await page.click('button:has-text("New Experiment")');
+    await expect(page.getByRole('dialog')).toBeVisible();
+
+    await page.getByLabel(/experiment title/i).fill('E2E Test Study');
+    await page.click('button:has-text("Create Experiment")');
+
+    // Modal closes and new experiment appears in the list
+    await expect(page.getByRole('dialog')).not.toBeVisible();
+    await expect(page.getByText('E2E Test Study')).toBeVisible();
+
+    // ── Navigate into experiment ──────────────────────────────────
+    await page.click('text=E2E Test Study');
+    await expect(page.url()).toContain('/experiments/');
+
+    // ── Add animal ────────────────────────────────────────────────
+    await page.click('button:has-text("Add Animal")');
+    await expect(page.getByRole('dialog')).toBeVisible();
+
+    await page.getByLabel(/animal id/i).fill('M-E2E-001');
+    await page.getByLabel(/animal name/i).fill('TestMouse');
+    await page.click('button:has-text("Add Animal")');
+
+    await expect(page.getByRole('dialog')).not.toBeVisible();
+    await expect(page.getByText('TestMouse')).toBeVisible();
+
+    // ── Navigate into animal ──────────────────────────────────────
+    await page.click('text=TestMouse');
+    await expect(page.url()).toContain('/animals/');
+
+    // ── Log daily status ──────────────────────────────────────────
+    await page.click('button:has-text("Log Daily Status")');
+    await expect(page.getByRole('dialog')).toBeVisible();
+
+    // Date is pre-filled with today; add vitals
+    await page.getByLabel(/vitals/i).fill('HR 70, Temp 37.0');
+    await page.getByLabel(/treatment/i).fill('Control');
+    await page.click('button:has-text("Log Status")');
+
+    await expect(page.getByRole('dialog')).not.toBeVisible();
+    await expect(page.getByText('HR 70, Temp 37.0')).toBeVisible();
+  });
+});
+
+test.describe('UX Flow — validation error states', () => {
+  test('empty experiment title shows error', async ({ page }) => {
+    await page.goto(BASE_URL);
+    await page.click('button:has-text("New Experiment")');
+    await page.click('button:has-text("Create Experiment")');
+    await expect(page.getByRole('alert')).toContainText(/title is required/i);
+  });
+
+  test('empty animal fields show errors', async ({ page }) => {
+    await page.goto(BASE_URL);
+
+    // Need an experiment to navigate into — create one first
+    await page.click('button:has-text("New Experiment")');
+    await page.getByLabel(/experiment title/i).fill('UX Test Study');
+    await page.click('button:has-text("Create Experiment")');
+    await page.click('text=UX Test Study');
+
+    await page.click('button:has-text("Add Animal")');
+    await page.click('button:has-text("Add Animal")'); // submit without filling
+    const alerts = page.getByRole('alert');
+    await expect(alerts).toHaveCount(2); // ID + Name errors
+  });
+
+  test('missing date on daily status shows error', async ({ page }) => {
+    await page.goto(BASE_URL);
+
+    // Create experiment + animal to get to daily status form
+    await page.click('button:has-text("New Experiment")');
+    await page.getByLabel(/experiment title/i).fill('Date Test Study');
+    await page.click('button:has-text("Create Experiment")');
+    await page.click('text=Date Test Study');
+
+    await page.click('button:has-text("Add Animal")');
+    await page.getByLabel(/animal id/i).fill('M-DT-001');
+    await page.getByLabel(/animal name/i).fill('DateTestMouse');
+    await page.click('button:has-text("Add Animal")');
+    await page.click('text=DateTestMouse');
+
+    await page.click('button:has-text("Log Daily Status")');
+    // Clear the date field
+    await page.getByLabel(/date/i).fill('');
+    await page.click('button:has-text("Log Status")');
+    await expect(page.getByRole('alert')).toContainText(/date is required/i);
+  });
+});

frontend/package.json

@@ -6,9 +6,8 @@
     "dev": "vite",
     "build": "vite build",
     "preview": "vite preview",
-    "test": "vitest run",
-    "test:watch": "vitest",
-    "test:coverage": "vitest run --coverage",
+    "test": "node --max-old-space-size=8192 node_modules/.bin/jest --runInBand --forceExit",
+    "test:coverage": "node --max-old-space-size=8192 node_modules/.bin/jest --runInBand --forceExit --coverage",
     "test:e2e": "playwright test"
   },
   "dependencies": {
@@ -16,22 +15,40 @@
     "date-fns": "^3.6.0",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
-    "react-router-dom": "^6.24.0"
+    "react-router-dom": "^6.24.0",
+    "recharts": "^2.15.4"
   },
   "devDependencies": {
+    "@babel/core": "^7.24.7",
+    "@babel/preset-env": "^7.24.7",
+    "@babel/preset-react": "^7.24.6",
     "@playwright/test": "^1.44.1",
     "@testing-library/jest-dom": "^6.4.6",
-    "@testing-library/react": "^16.0.0",
+    "@testing-library/react": "^14.3.1",
     "@testing-library/user-event": "^14.5.2",
-    "@types/react": "^18.3.3",
-    "@types/react-dom": "^18.3.0",
     "@vitejs/plugin-react": "^4.2.1",
-    "@vitest/coverage-v8": "^1.6.0",
     "autoprefixer": "^10.4.19",
-    "jsdom": "^24.1.0",
+    "babel-jest": "^29.7.0",
+    "identity-obj-proxy": "^3.0.0",
+    "jest": "^29.7.0",
+    "jest-environment-jsdom": "^29.7.0",
     "postcss": "^8.4.39",
     "tailwindcss": "^3.4.4",
-    "vite": "^4.5.3",
-    "vitest": "^1.6.0"
+    "vite": "^4.5.3"
+  },
+  "jest": {
+    "testEnvironment": "jsdom",
+    "setupFilesAfterEnv": [
+      "<rootDir>/tests/setup.js"
+    ],
+    "testMatch": [
+      "**/tests/**/*.test.{js,jsx}"
+    ],
+    "transform": {
+      "^.+\\.[jt]sx?$": "babel-jest"
+    },
+    "moduleNameMapper": {
+      "\\.(css|less|scss|sass)$": "identity-obj-proxy"
+    }
   }
 }

frontend/playwright.config.js

@@ -0,0 +1,14 @@
+const { defineConfig, devices } = require('@playwright/test');
+
+module.exports = defineConfig({
+  testDir: './e2e',
+  timeout: 30000,
+  retries: process.env.CI ? 2 : 0,
+  use: {
+    baseURL: process.env.E2E_BASE_URL || 'http://localhost:52867',
+    trace: 'on-first-retry',
+  },
+  projects: [
+    { name: 'chromium', use: { ...devices['Desktop Chrome'] } },
+  ],
+});

frontend/src/App.jsx

@@ -1,8 +1,11 @@
-import React from 'react';
+import React, { useEffect, useState } from 'react';
 import { Routes, Route, Link, useLocation } from 'react-router-dom';
+import { systemApi } from './api/client';
 import Dashboard from './pages/Dashboard';
 import ExperimentDetail from './pages/ExperimentDetail';
 import AnimalDetail from './pages/AnimalDetail';
+import DailyStatusDetail from './pages/DailyStatusDetail';
+import ExperimentDayView from './pages/ExperimentDayView';
 
 function Navbar() {
   return (
@@ -33,18 +36,35 @@ function NotFound() {
   );
 }
 
+function Footer() {
+  const [dbTimezone, setDbTimezone] = useState(null);
+  useEffect(() => {
+    systemApi.info().then((d) => setDbTimezone(d.dbTimezone)).catch(() => {});
+  }, []);
+  return (
+    <footer className="border-t border-gray-200 mt-12 py-3">
+      <div className="max-w-5xl mx-auto px-4 text-xs text-gray-400 text-right">
+        Database timezone: <span className="font-mono">{dbTimezone ?? '…'}</span>
+      </div>
+    </footer>
+  );
+}
+
 export default function App() {
   return (
-    <div className="min-h-screen bg-gray-50">
+    <div className="min-h-screen bg-gray-50 flex flex-col">
       <Navbar />
-      <main>
+      <main className="flex-1">
         <Routes>
           <Route path="/" element={<Dashboard />} />
           <Route path="/experiments/:id" element={<ExperimentDetail />} />
+          <Route path="/experiments/:id/day/:date" element={<ExperimentDayView />} />
           <Route path="/animals/:id" element={<AnimalDetail />} />
+          <Route path="/daily-statuses/:id" element={<DailyStatusDetail />} />
           <Route path="*" element={<NotFound />} />
         </Routes>
       </main>
+      <Footer />
     </div>
   );
 }

frontend/src/api/client.js

@@ -29,6 +29,18 @@ export const experimentsApi = {
   create: (data) => api.post('/experiments', data).then((r) => r.data),
   update: (id, data) => api.put(`/experiments/${id}`, data).then((r) => r.data),
   delete: (id) => api.delete(`/experiments/${id}`),
+  getTemplate: (id) => api.get(`/experiments/${id}/template`).then((r) => r.data),
+  updateTemplate: (id, template) => api.put(`/experiments/${id}/template`, template).then((r) => r.data),
+  getSubjectTemplate: (id) => api.get(`/experiments/${id}/subject-template`).then((r) => r.data),
+  updateSubjectTemplate: (id, template) => api.put(`/experiments/${id}/subject-template`, template).then((r) => r.data),
+  savePlotConfig: (id, config) => api.put(`/experiments/${id}/plot-config`, config).then((r) => r.data),
+  // opts: { date?: string, analysisOnly?: boolean }
+  getDailyStatuses: (id, opts) => {
+    const params = typeof opts === 'string' ? { date: opts } : (opts ?? {});
+    return api.get(`/experiments/${id}/daily-statuses`, { params }).then((r) => r.data);
+  },
+  getDayStatuses: (id, date) => api.get(`/experiments/${id}/daily-statuses`, { params: { date } }).then((r) => r.data),
+  getCalendar: (id, field) => api.get(`/experiments/${id}/calendar`, { params: { field } }).then((r) => r.data),
 };
 
 // ── Animals ───────────────────────────────────────────────────────────────────
@@ -39,6 +51,8 @@ export const animalsApi = {
   create: (data) => api.post('/animals', data).then((r) => r.data),
   update: (id, data) => api.put(`/animals/${id}`, data).then((r) => r.data),
   delete: (id) => api.delete(`/animals/${id}`),
+  updateCsvConfig: (id, config) =>
+    api.patch(`/animals/${id}/csv-config`, config).then((r) => r.data),
 };
 
 // ── Daily Statuses ─────────────────────────────────────────────────────────────
@@ -49,9 +63,30 @@ export const dailyStatusesApi = {
   create: (data) => api.post('/daily-statuses', data).then((r) => r.data),
   update: (id, data) => api.put(`/daily-statuses/${id}`, data).then((r) => r.data),
   delete: (id) => api.delete(`/daily-statuses/${id}`),
+  updateAnalysisSummary: (id, data) => api.put(`/daily-statuses/${id}/analysis-summary`, data).then((r) => r.data),
 };
 
 // ── Audit Logs ────────────────────────────────────────────────────────────────
 export const auditLogsApi = {
   list: (params) => api.get('/audit-logs', { params }).then((r) => r.data),
 };
+
+// ── System ────────────────────────────────────────────────────────────────────
+export const systemApi = {
+  info: () => api.get('/info').then((r) => r.data),
+};
+
+// ── Session Files ─────────────────────────────────────────────────────────────
+export const sessionFilesApi = {
+  list:   (statusId) => api.get(`/daily-statuses/${statusId}/files`).then((r) => r.data),
+  create: (statusId, files) => api.post(`/daily-statuses/${statusId}/files`, files).then((r) => r.data),
+  delete: (id) => api.delete(`/session-files/${id}`),
+};
+
+// ── Analyses ──────────────────────────────────────────────────────────────────
+export const analysesApi = {
+  listForStatus: (statusId) => api.get(`/daily-statuses/${statusId}/analyses`).then((r) => r.data),
+  create: (statusId, data) => api.post(`/daily-statuses/${statusId}/analyses`, data).then((r) => r.data),
+  get: (id) => api.get(`/analyses/${id}`).then((r) => r.data),
+  delete: (id) => api.delete(`/analyses/${id}`),
+};

frontend/src/components/AnalysisCharts.jsx

@@ -0,0 +1,734 @@
+import React, { useState, useMemo, useEffect, useRef } from 'react';
+import { format } from 'date-fns';
+import {
+  LineChart, Line, XAxis, YAxis, CartesianGrid, Tooltip,
+  Legend, ResponsiveContainer,
+} from 'recharts';
+import { SubjectSidebar } from './SubjectSidebar';
+import { sortPayloadByValueDesc, toggleInSet, setIdsHidden, serializePlotConfig, readPlotConfig } from '../lib/crossSubjectChart';
+
+// ── Color palettes ─────────────────────────────────────────────────────────────
+
+const CAT_COLORS   = { Success: '#22c55e', Failure: '#ef4444', Other: '#9ca3af' };
+const EXTRA_CAT    = ['#f59e0b', '#a855f7', '#ec4899', '#14b8a6', '#f97316'];
+const GROUP_COLORS = ['#6366f1', '#f59e0b', '#22c55e', '#ef4444', '#a855f7', '#14b8a6', '#ec4899', '#f97316', '#84cc16', '#06b6d4'];
+
+function catColor(cat, idx = 0) {
+  return CAT_COLORS[cat] ?? EXTRA_CAT[idx % EXTRA_CAT.length];
+}
+
+// ── Shared tooltip ─────────────────────────────────────────────────────────────
+
+function ChartTooltip({ active, payload, label, labelKey = 'dateStr', unit = '' }) {
+  if (!active || !payload?.length) return null;
+  const header = payload[0]?.payload?.[labelKey] ?? `Day ${label}`;
+  return (
+    <div className="bg-white border border-gray-200 rounded shadow-sm px-3 py-2 text-xs space-y-0.5">
+      <p className="font-semibold text-gray-700 mb-1">{header}</p>
+      {payload.map((p) => (
+        <p key={p.dataKey} style={{ color: p.stroke ?? p.color }}>
+          {p.name}: {p.value != null ? `${p.value}${unit}` : '—'}
+        </p>
+      ))}
+    </div>
+  );
+}
+
+// ── Shared helpers ─────────────────────────────────────────────────────────────
+
+const DAYS_REACH_RE = /#?\s*days?\s*reach/i;
+const SELECT_CLS    = 'border border-gray-200 rounded px-1.5 py-0.5 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400';
+const INPUT_CLS     = 'w-16 border border-gray-200 rounded px-1.5 py-0.5 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400';
+const STEP_OPTIONS  = [1, 2, 5, 10];
+
+function defaultXField(fields) {
+  return fields.find((f) => DAYS_REACH_RE.test(f.label))?.fieldId ?? '__days__';
+}
+
+function numericFieldVal(status, field) {
+  if (!field) return null;
+  const raw = field.builtin ? status[field.key] : status.custom_fields?.[field.fieldId];
+  const n = parseFloat(raw);
+  return isNaN(n) ? null : n;
+}
+
+function buildTicks(data, step) {
+  const xs = data.map((d) => d.x).filter((x) => x != null && isFinite(x));
+  if (!xs.length) return undefined;
+  const lo = Math.floor(Math.min(...xs));
+  const hi = Math.ceil(Math.max(...xs));
+  const ticks = [];
+  for (let t = Math.ceil(lo / step) * step; t <= hi; t += step) ticks.push(t);
+  if (!ticks.length || ticks[0] > lo) ticks.unshift(lo);
+  if (ticks[ticks.length - 1] < hi) ticks.push(hi);
+  return ticks;
+}
+
+function TickStepControl({ value, onChange }) {
+  return (
+    <div className="flex items-center gap-1.5 text-xs">
+      <span className="text-gray-400">Tick every</span>
+      <div className="flex rounded border border-gray-200 overflow-hidden">
+        {STEP_OPTIONS.map((s) => (
+          <button key={s} type="button" onClick={() => onChange(s)}
+            className={`px-2 py-0.5 transition-colors border-l border-gray-200 first:border-l-0
+              ${value === s ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+            {s}
+          </button>
+        ))}
+      </div>
+    </div>
+  );
+}
+
+// ── Per-chart customisation hook & UI ──────────────────────────────────────────
+
+const HEIGHT_OPTIONS = [
+  { label: 'S', value: 140 },
+  { label: 'M', value: 220 },
+  { label: 'L', value: 340 },
+];
+
+function useChartSettings(defaultHeight, initial = {}) {
+  const [expanded,       setExpanded]       = useState(false);
+  const [height,         setHeight]         = useState(initial.height ?? defaultHeight);
+  const [yMin,           setYMin]           = useState(initial.yMin ?? '');
+  const [yMax,           setYMax]           = useState(initial.yMax ?? '');
+  const [xZoomMin,       setXZoomMin]       = useState(initial.xZoomMin ?? '');
+  const [xZoomMax,       setXZoomMax]       = useState(initial.xZoomMax ?? '');
+  const [xFieldOverride, setXFieldOverride] = useState(initial.xFieldOverride ?? null); // null → use parent's xField
+
+  const yDomain = useMemo(() => [
+    yMin !== '' ? parseFloat(yMin) : 'auto',
+    yMax !== '' ? parseFloat(yMax) : 'auto',
+  ], [yMin, yMax]);
+
+  const xDomain = useMemo(() => {
+    const hasMin = xZoomMin !== '';
+    const hasMax = xZoomMax !== '';
+    if (!hasMin && !hasMax) return null;
+    return [hasMin ? parseFloat(xZoomMin) : 'dataMin', hasMax ? parseFloat(xZoomMax) : 'dataMax'];
+  }, [xZoomMin, xZoomMax]);
+
+  const isDirty = yMin !== '' || yMax !== '' || xZoomMin !== '' || xZoomMax !== ''
+    || xFieldOverride !== null || height !== defaultHeight;
+
+  const snapshot = useMemo(
+    () => ({ height, yMin, yMax, xZoomMin, xZoomMax, xFieldOverride }),
+    [height, yMin, yMax, xZoomMin, xZoomMax, xFieldOverride],
+  );
+
+  function reset() {
+    setHeight(defaultHeight);
+    setYMin(''); setYMax('');
+    setXZoomMin(''); setXZoomMax('');
+    setXFieldOverride(null);
+  }
+
+  return {
+    expanded, setExpanded,
+    height, setHeight,
+    yMin, setYMin, yMax, setYMax,
+    xZoomMin, setXZoomMin, xZoomMax, setXZoomMax,
+    xFieldOverride, setXFieldOverride,
+    yDomain, xDomain, isDirty, reset, snapshot,
+  };
+}
+
+function ChartHeader({ title, isDirty, expanded, onToggle }) {
+  return (
+    <div className="flex items-center justify-between mb-2">
+      <p className="text-xs text-gray-500 font-medium">{title}</p>
+      <button type="button" onClick={onToggle}
+        className={[
+          'text-xs px-2 py-0.5 rounded border transition-colors',
+          expanded
+            ? 'bg-gray-100 border-gray-300 text-gray-700'
+            : isDirty
+              ? 'bg-indigo-50 border-indigo-200 text-indigo-600'
+              : 'bg-white border-gray-200 text-gray-400 hover:text-gray-700 hover:border-gray-300',
+        ].join(' ')}
+      >
+        {expanded ? '▲ collapse' : '▾ customize'}
+      </button>
+    </div>
+  );
+}
+
+// Shown only when the chart card is expanded — renders per-chart controls.
+function ChartSettingsBar({ s, xAxisFields, globalXField, extra }) {
+  return (
+    <div className="mb-3 p-3 bg-gray-50 border border-gray-100 rounded-lg flex flex-wrap gap-x-5 gap-y-2 items-center text-xs">
+
+      {/* Size */}
+      <div className="flex items-center gap-1.5">
+        <span className="text-gray-400 shrink-0">Size:</span>
+        <div className="flex rounded border border-gray-200 overflow-hidden">
+          {HEIGHT_OPTIONS.map((opt) => (
+            <button key={opt.value} type="button" onClick={() => s.setHeight(opt.value)}
+              className={`px-2 py-0.5 transition-colors border-l border-gray-200 first:border-l-0
+                ${s.height === opt.value ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+              {opt.label}
+            </button>
+          ))}
+        </div>
+      </div>
+
+      {/* Y range */}
+      <div className="flex items-center gap-1.5">
+        <span className="text-gray-400 shrink-0">Y range:</span>
+        <input type="number" placeholder="min" value={s.yMin} onChange={(e) => s.setYMin(e.target.value)} className={INPUT_CLS} />
+        <span className="text-gray-300">–</span>
+        <input type="number" placeholder="max" value={s.yMax} onChange={(e) => s.setYMax(e.target.value)} className={INPUT_CLS} />
+      </div>
+
+      {/* X zoom */}
+      <div className="flex items-center gap-1.5">
+        <span className="text-gray-400 shrink-0">X zoom:</span>
+        <input type="number" placeholder="min" value={s.xZoomMin} onChange={(e) => s.setXZoomMin(e.target.value)} className={INPUT_CLS} />
+        <span className="text-gray-300">–</span>
+        <input type="number" placeholder="max" value={s.xZoomMax} onChange={(e) => s.setXZoomMax(e.target.value)} className={INPUT_CLS} />
+      </div>
+
+      {/* Per-chart X axis field override */}
+      {xAxisFields.length > 0 && (
+        <div className="flex items-center gap-1.5">
+          <span className="text-gray-400 shrink-0">X data:</span>
+          <select
+            value={s.xFieldOverride ?? globalXField}
+            onChange={(e) => {
+              const v = e.target.value;
+              s.setXFieldOverride(v === globalXField ? null : v);
+            }}
+            className={SELECT_CLS}
+          >
+            <option value="__days__"># Days Reach (ordinal)</option>
+            {xAxisFields.map((f) => <option key={f.fieldId} value={f.fieldId}>{f.label}</option>)}
+          </select>
+        </div>
+      )}
+
+      {/* Slot for chart-specific controls (e.g. Y line visibility) */}
+      {extra}
+
+      {s.isDirty && (
+        <button type="button" onClick={s.reset}
+          className="text-xs text-red-400 hover:text-red-600 transition-colors ml-auto">
+          ↺ Reset
+        </button>
+      )}
+    </div>
+  );
+}
+
+// ── Pure data-computation helpers ──────────────────────────────────────────────
+
+function computeSubjectChartData(xField, statuses, xAxisFields) {
+  const xAxisField = xAxisFields.find((f) => f.fieldId === xField);
+  const xLabel     = xAxisField ? xAxisField.label : '# Days Reach';
+
+  const withMetrics = statuses
+    .filter((s) => s.analysis_summary?.total != null)
+    .sort((a, b) => String(a.date).localeCompare(String(b.date)));
+
+  const rows = withMetrics.map((s, i) => {
+    const xVal    = xField === '__days__' || !xAxisField ? i + 1 : numericFieldVal(s, xAxisField);
+    const dateStr = format(new Date(String(s.date).slice(0, 10) + 'T12:00:00'), 'MMM d');
+    const { counts = {}, total, success_rate } = s.analysis_summary;
+    return { _x: xVal, dateStr, total, rate: success_rate != null ? +(success_rate * 100).toFixed(1) : null, ...counts };
+  }).filter((r) => r._x != null).sort((a, b) => a._x - b._x);
+
+  const data = rows.map((r) => ({ ...r, x: r._x }));
+
+  const catSet = new Set();
+  for (const d of data) {
+    for (const k of Object.keys(d)) {
+      if (!['x', '_x', 'dateStr', 'total', 'rate'].includes(k)) catSet.add(k);
+    }
+  }
+  return { data, cats: [...catSet], xLabel };
+}
+
+function computeExpChartData(xField, chartType, metric, animalRows, lines, xAxisFields) {
+  // chartType: 'count' | 'rate'
+  const xAxisField = xAxisFields.find((f) => f.fieldId === xField);
+  const xLabel     = xAxisField ? xAxisField.label : '# Days Reach';
+
+  function getX(row, dayIndex) {
+    if (xField === '__days__') return dayIndex + 1;
+    return numericFieldVal(row, xAxisField);
+  }
+
+  if (xField === '__days__') {
+    const maxDay = Math.max(0, ...lines.map((l) => animalRows[l.id].length));
+    if (maxDay === 0) return { data: [], xLabel };
+    const data = Array.from({ length: maxDay }, (_, i) => ({ x: i + 1 }));
+    for (const line of lines) {
+      animalRows[line.id].forEach((row, i) => {
+        const s = row.analysis_summary;
+        if (chartType === 'count') {
+          data[i][line.id] = metric === 'total' ? s.total : (s.counts?.[metric] ?? null);
+        } else {
+          data[i][line.id] = s.success_rate != null ? +(s.success_rate * 100).toFixed(1) : null;
+        }
+      });
+    }
+    return { data, xLabel };
+  }
+
+  // Field-based x axis
+  const allPts = [];
+  for (const line of lines) {
+    animalRows[line.id].forEach((row, i) => {
+      const x = getX(row, i);
+      if (x !== null) allPts.push({ x, animalId: line.id, summary: row.analysis_summary });
+    });
+  }
+  const sortedX = [...new Set(allPts.map((p) => p.x))].sort((a, b) => a - b);
+  if (sortedX.length === 0) return { data: [], xLabel };
+
+  const data = sortedX.map((x) => {
+    const pt = { x };
+    for (const p of allPts.filter((pp) => pp.x === x)) {
+      const s = p.summary;
+      if (chartType === 'count') {
+        pt[p.animalId] = metric === 'total' ? s.total : (s.counts?.[metric] ?? null);
+      } else {
+        pt[p.animalId] = s.success_rate != null ? +(s.success_rate * 100).toFixed(1) : null;
+      }
+    }
+    return pt;
+  });
+  return { data, xLabel };
+}
+
+// ── Subject charts ─────────────────────────────────────────────────────────────
+
+export function SubjectAnalysisCharts({ statuses, dailyTemplate }) {
+  const xAxisFields = useMemo(
+    () => (dailyTemplate ?? []).filter((f) => f.active),
+    [dailyTemplate],
+  );
+  const [xField,    setXField]    = useState(() => defaultXField(xAxisFields));
+  const [tickStep,  setTickStep]  = useState(1);
+
+  const countsS = useChartSettings(200);
+  const rateS   = useChartSettings(160);
+
+  // Shared base computation — used by both charts when no override is set
+  const sharedData = useMemo(
+    () => computeSubjectChartData(xField, statuses, xAxisFields),
+    [xField, statuses, xAxisFields],
+  );
+
+  // Per-chart overrides: only recompute when the override differs from the shared field
+  const countsData = useMemo(() => {
+    const ef = countsS.xFieldOverride;
+    if (!ef || ef === xField) return sharedData;
+    return computeSubjectChartData(ef, statuses, xAxisFields);
+  }, [countsS.xFieldOverride, xField, sharedData, statuses, xAxisFields]);
+
+  const rateData = useMemo(() => {
+    const ef = rateS.xFieldOverride;
+    if (!ef || ef === xField) return sharedData;
+    return computeSubjectChartData(ef, statuses, xAxisFields);
+  }, [rateS.xFieldOverride, xField, sharedData, statuses, xAxisFields]);
+
+  const countsTicks = useMemo(() => buildTicks(countsData.data, tickStep), [countsData.data, tickStep]);
+  const rateTicks   = useMemo(() => buildTicks(rateData.data,   tickStep), [rateData.data,   tickStep]);
+
+  // Y-line visibility for the counts chart (null = show all)
+  const [visibleCats, setVisibleCats] = useState(null);
+  useEffect(() => { setVisibleCats(null); }, [countsData.cats.join(',')]); // reset when cats change
+
+  if (sharedData.data.length === 0) return null;
+
+  function toggleCat(cat) {
+    setVisibleCats((prev) => {
+      if (prev === null) return new Set([cat]);
+      const next = new Set(prev);
+      next.has(cat) ? next.delete(cat) : next.add(cat);
+      return next.size === 0 ? null : next;
+    });
+  }
+
+  function xAxisProps(data, ticks, s) {
+    const ef         = s.xFieldOverride ?? xField;
+    const xAxisField = xAxisFields.find((f) => f.fieldId === ef);
+    const xLabel     = xAxisField ? xAxisField.label : '# Days Reach';
+    const domain     = s.xDomain ?? (ticks?.length ? [ticks[0], ticks[ticks.length - 1]] : ['auto', 'auto']);
+    return { dataKey: 'x', type: 'number', tick: { fontSize: 10 }, ticks, domain, allowDecimals: false,
+      label: { value: xLabel, position: 'insideBottomRight', offset: -4, fontSize: 10 } };
+  }
+
+  return (
+    <div className="bg-white border border-gray-200 rounded-xl p-5 mb-6 space-y-5">
+      {/* Global controls */}
+      <div className="flex items-center flex-wrap gap-3">
+        <h2 className="text-sm font-semibold text-gray-700 uppercase tracking-wide">Session metrics over time</h2>
+        <div className="flex items-center gap-1.5 text-xs">
+          <span className="text-gray-400">X axis:</span>
+          <select value={xField} onChange={(e) => setXField(e.target.value)} className={SELECT_CLS}>
+            <option value="__days__"># Days Reach (ordinal)</option>
+            {xAxisFields.map((f) => <option key={f.fieldId} value={f.fieldId}>{f.label}</option>)}
+          </select>
+        </div>
+        <TickStepControl value={tickStep} onChange={setTickStep} />
+      </div>
+
+      {/* Chart 1 — counts */}
+      <div>
+        <ChartHeader title="Attempts per session" isDirty={countsS.isDirty} expanded={countsS.expanded} onToggle={() => countsS.setExpanded((e) => !e)} />
+        {countsS.expanded && (
+          <ChartSettingsBar s={countsS} xAxisFields={xAxisFields} globalXField={xField}
+            extra={
+              countsData.cats.length > 0 && (
+                <div className="flex items-center gap-2 flex-wrap">
+                  <span className="text-gray-400 shrink-0">Y lines:</span>
+                  {countsData.cats.map((cat, i) => {
+                    const on = visibleCats === null || visibleCats.has(cat);
+                    return (
+                      <button key={cat} type="button" onClick={() => toggleCat(cat)}
+                        style={{ color: catColor(cat, i), borderColor: on ? catColor(cat, i) : '#e5e7eb' }}
+                        className={`px-2 py-0.5 rounded border text-xs transition-opacity ${on ? 'opacity-100' : 'opacity-35'}`}>
+                        {cat}
+                      </button>
+                    );
+                  })}
+                </div>
+              )
+            }
+          />
+        )}
+        <ResponsiveContainer width="100%" height={countsS.height}>
+          <LineChart data={countsData.data} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+            <CartesianGrid strokeDasharray="3 3" stroke="#f3f4f6" />
+            <XAxis {...xAxisProps(countsData.data, countsTicks, countsS)} />
+            <YAxis tick={{ fontSize: 10 }} width={30} allowDecimals={false} domain={countsS.yDomain} />
+            <Tooltip content={<ChartTooltip labelKey="dateStr" />} />
+            <Legend wrapperStyle={{ fontSize: 11 }} />
+            {countsData.cats
+              .filter((cat) => visibleCats === null || visibleCats.has(cat))
+              .map((cat, i) => (
+                <Line key={cat} type="monotone" dataKey={cat} stroke={catColor(cat, i)} strokeWidth={2}
+                  dot={{ r: 3 }} activeDot={{ r: 4 }} connectNulls isAnimationActive={false} />
+              ))}
+            <Line type="monotone" dataKey="total" name="Total" stroke="#3b82f6" strokeWidth={1.5}
+              strokeDasharray="5 3" dot={{ r: 3 }} connectNulls isAnimationActive={false} />
+          </LineChart>
+        </ResponsiveContainer>
+      </div>
+
+      {/* Chart 2 — success rate */}
+      <div>
+        <ChartHeader title="Success rate (%)" isDirty={rateS.isDirty} expanded={rateS.expanded} onToggle={() => rateS.setExpanded((e) => !e)} />
+        {rateS.expanded && (
+          <ChartSettingsBar s={rateS} xAxisFields={xAxisFields} globalXField={xField} />
+        )}
+        <ResponsiveContainer width="100%" height={rateS.height}>
+          <LineChart data={rateData.data} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+            <CartesianGrid strokeDasharray="3 3" stroke="#f3f4f6" />
+            <XAxis {...xAxisProps(rateData.data, rateTicks, rateS)} />
+            <YAxis tick={{ fontSize: 10 }} width={36}
+              domain={rateS.yDomain[0] !== 'auto' || rateS.yDomain[1] !== 'auto' ? rateS.yDomain : [0, 100]}
+              tickFormatter={(v) => `${v}%`} />
+            <Tooltip content={<ChartTooltip unit="%" labelKey="dateStr" />} />
+            <Line type="monotone" dataKey="rate" name="Success rate" stroke="#6366f1" strokeWidth={2}
+              dot={{ r: 3 }} connectNulls isAnimationActive={false} />
+          </LineChart>
+        </ResponsiveContainer>
+      </div>
+    </div>
+  );
+}
+
+// ── Experiment charts ──────────────────────────────────────────────────────────
+
+const METRIC_OPTIONS = [
+  { value: 'total',   label: 'Total attempts' },
+  { value: 'Success', label: 'Success count'  },
+  { value: 'Failure', label: 'Failure count'  },
+];
+
+export function ExperimentAnalysisCharts({ animals, experimentStatuses, subjectTemplate, dailyTemplate, plotConfig, onPersistConfig }) {
+  const groupableFields = useMemo(() => (subjectTemplate ?? []).filter((f) => f.active), [subjectTemplate]);
+  const xAxisFields     = useMemo(() => (dailyTemplate    ?? []).filter((f) => f.active), [dailyTemplate]);
+
+  const defaultGroup = (groupableFields.find((f) => /^group$/i.test(f.label)) ?? groupableFields[0])?.fieldId ?? '';
+  // Read the saved config exactly once (component only mounts after the experiment loads).
+  const initialConfigRef = useRef(null);
+  if (initialConfigRef.current === null) initialConfigRef.current = readPlotConfig(plotConfig);
+  const initialConfig = initialConfigRef.current;
+  const [groupBy,  setGroupBy]  = useState(initialConfig.groupBy ?? defaultGroup);
+  const [metric,   setMetric]   = useState(initialConfig.metric ?? 'total');
+  const [xField,   setXField]   = useState(() => initialConfig.xField ?? defaultXField(xAxisFields));
+  const [tickStep, setTickStep] = useState(initialConfig.tickStep ?? 1);
+
+  // Cross-subject interaction state (client-only; global across both charts)
+  const [sidebarOpen,        setSidebarOpen]        = useState(initialConfig.sidebarOpen);
+  const [hiddenSubjects,     setHiddenSubjects]     = useState(() => new Set(initialConfig.hiddenSubjects));
+  const [highlightedSubject, setHighlightedSubject] = useState(null);
+
+  const toggleHidden = (id)          => setHiddenSubjects((prev) => toggleInSet(prev, id));
+  const toggleGroup  = (ids, hidden) => setHiddenSubjects((prev) => setIdsHidden(prev, ids, hidden));
+  const showAll      = ()            => setHiddenSubjects(new Set());
+
+  const countsS = useChartSettings(200, initialConfig.counts);
+  const rateS   = useChartSettings(160, initialConfig.rate);
+
+  // ── Persist display settings (debounced auto-save) ────────────────────────────
+  const [saveState, setSaveState] = useState('idle'); // 'idle' | 'saving' | 'saved' | 'error'
+
+  const currentConfig = useMemo(
+    () => serializePlotConfig({
+      xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen,
+      counts: countsS.snapshot, rate: rateS.snapshot,
+    }),
+    [xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen, countsS.snapshot, rateS.snapshot],
+  );
+
+  // Keep the latest persist callback in a ref so the save effect does not re-run
+  // when the parent passes a new inline function each render.
+  const persistRef = useRef(onPersistConfig);
+  persistRef.current = onPersistConfig;
+
+  const lastSavedRef = useRef(null);
+  useEffect(() => {
+    const serialized = JSON.stringify(currentConfig);
+    if (lastSavedRef.current === null) { lastSavedRef.current = serialized; return; } // skip initial (hydration)
+    // Reverted to the last-saved value before the debounce fired → nothing pending.
+    if (serialized === lastSavedRef.current) { setSaveState('idle'); return; }
+    if (!persistRef.current) { lastSavedRef.current = serialized; setSaveState('idle'); return; }
+    setSaveState('saving');
+    const t = setTimeout(() => {
+      Promise.resolve(persistRef.current(currentConfig))
+        .then(() => { lastSavedRef.current = serialized; setSaveState('saved'); })
+        .catch(() => setSaveState('error'));
+    }, 1000);
+    return () => clearTimeout(t);
+  }, [currentConfig]);
+
+  // Step 1: animalRows — does NOT depend on xField; shared by both charts
+  const { animalRows, lines } = useMemo(() => {
+    const animalGroup = {};
+    for (const animal of animals) {
+      const raw = groupBy ? animal.subject_info?.[groupBy] : null;
+      animalGroup[animal.id] = raw != null && raw !== '' ? String(raw) : '—';
+    }
+    const groups = [...new Set(Object.values(animalGroup))].sort();
+
+    const statusesByAnimal = {};
+    for (const s of experimentStatuses) {
+      if (!statusesByAnimal[s.animal_id]) statusesByAnimal[s.animal_id] = [];
+      statusesByAnimal[s.animal_id].push(s);
+    }
+    const animalRows = {};
+    for (const animal of animals) {
+      animalRows[animal.id] = (statusesByAnimal[animal.id] ?? [])
+        .filter((s) => s.analysis_summary?.total != null)
+        .sort((a, b) => String(a.date).localeCompare(String(b.date)));
+    }
+
+    const lines = animals
+      .filter((a) => animalRows[a.id]?.length > 0)
+      .map((a) => ({
+        id:    a.id,
+        name:  a.animal_name,
+        group: animalGroup[a.id],
+        color: GROUP_COLORS[groups.indexOf(animalGroup[a.id]) % GROUP_COLORS.length],
+      }));
+
+    return { animalRows, lines };
+  }, [animals, experimentStatuses, groupBy]);
+
+  // Step 2: count chart data — depends on xField for counts + metric
+  const { data: countData, xLabel: countsXLabel } = useMemo(() => {
+    if (lines.length === 0) return { data: [], xLabel: '' };
+    const ef = countsS.xFieldOverride ?? xField;
+    return computeExpChartData(ef, 'count', metric, animalRows, lines, xAxisFields);
+  }, [animalRows, lines, countsS.xFieldOverride, xField, metric, xAxisFields]);
+
+  // Step 3: rate chart data — depends on xField for rate
+  const { data: rateData, xLabel: rateXLabel } = useMemo(() => {
+    if (lines.length === 0) return { data: [], xLabel: '' };
+    const ef = rateS.xFieldOverride ?? xField;
+    return computeExpChartData(ef, 'rate', null, animalRows, lines, xAxisFields);
+  }, [animalRows, lines, rateS.xFieldOverride, xField, xAxisFields]);
+
+  const countsTicks = useMemo(() => buildTicks(countData, tickStep), [countData, tickStep]);
+  const rateTicks   = useMemo(() => buildTicks(rateData,  tickStep), [rateData,  tickStep]);
+
+  const hasData = lines.length > 0;
+
+  function xAxisProps(data, ticks, s, fallbackLabel) {
+    const domain = s.xDomain ?? (ticks?.length ? [ticks[0], ticks[ticks.length - 1]] : ['auto', 'auto']);
+    const label  = (s.xFieldOverride ? xAxisFields.find((f) => f.fieldId === s.xFieldOverride)?.label : null) ?? fallbackLabel;
+    return { dataKey: 'x', type: 'number', tick: { fontSize: 10 }, ticks, domain, allowDecimals: false,
+      label: { value: label, position: 'insideBottomRight', offset: -4, fontSize: 10 } };
+  }
+
+  function ExpTooltip({ active, payload, label, unit = '' }) {
+    if (!active || !payload?.length) return null;
+    const rows = sortPayloadByValueDesc(payload);
+    return (
+      <div className="bg-white border border-gray-200 rounded shadow-sm px-3 py-2 text-xs space-y-0.5 max-h-48 overflow-y-auto">
+        <p className="font-semibold text-gray-700 mb-1">{label}</p>
+        {rows.map((p) => {
+          const line = lines.find((l) => l.id === p.dataKey);
+          return (
+            <p key={p.dataKey} style={{ color: p.stroke }}>
+              {line?.name ?? p.dataKey}{line?.group && line.group !== '—' ? ` (${line.group})` : ''}: {p.value}{unit}
+            </p>
+          );
+        })}
+      </div>
+    );
+  }
+
+  return (
+    <div className="bg-white border border-gray-200 rounded-xl p-5 mb-6 space-y-5">
+      {/* Global controls */}
+      <div className="flex items-center flex-wrap gap-3">
+        <h2 className="text-sm font-semibold text-gray-700 uppercase tracking-wide">Cross-subject metrics</h2>
+        <div className="flex items-center gap-1.5 text-xs">
+          <span className="text-gray-400">X axis:</span>
+          <select value={xField} onChange={(e) => setXField(e.target.value)} className={SELECT_CLS}>
+            <option value="__days__"># Days Reach (ordinal)</option>
+            {xAxisFields.map((f) => <option key={f.fieldId} value={f.fieldId}>{f.label}</option>)}
+          </select>
+        </div>
+        {groupableFields.length > 0 && (
+          <div className="flex items-center gap-1.5 text-xs">
+            <span className="text-gray-400">Color by:</span>
+            <select value={groupBy} onChange={(e) => setGroupBy(e.target.value)} className={SELECT_CLS}>
+              <option value="">— none —</option>
+              {groupableFields.map((f) => <option key={f.fieldId} value={f.fieldId}>{f.label}</option>)}
+            </select>
+          </div>
+        )}
+        <TickStepControl value={tickStep} onChange={setTickStep} />
+        {hasData && (
+          <div className="ml-auto flex items-center gap-2">
+            {saveState === 'saving' && <span className="text-xs text-gray-400">Saving…</span>}
+            {saveState === 'saved'  && <span className="text-xs text-emerald-500">Saved ✓</span>}
+            {saveState === 'error'  && <span className="text-xs text-amber-500">Couldn't save layout</span>}
+            <button type="button" onClick={() => setSidebarOpen((o) => !o)}
+              className={[
+                'text-xs px-2 py-0.5 rounded border transition-colors',
+                sidebarOpen
+                  ? 'bg-gray-100 border-gray-300 text-gray-700'
+                  : 'bg-white border-gray-200 text-gray-500 hover:text-gray-700 hover:border-gray-300',
+              ].join(' ')}>
+              {sidebarOpen ? '◂ Subjects' : '▸ Subjects'}
+            </button>
+          </div>
+        )}
+      </div>
+
+      {!hasData && (
+        <p className="text-sm text-gray-400 italic">No sessions with saved metrics yet.</p>
+      )}
+
+      {hasData && (
+        <div className="flex gap-3 items-start">
+          <div className="flex-1 min-w-0 space-y-5">
+          {/* Chart 1 — counts */}
+          <div>
+            <div className="flex items-center justify-between mb-2 flex-wrap gap-2">
+              <div className="flex items-center gap-3">
+                <p className="text-xs text-gray-500 font-medium">Count per session</p>
+                {/* Y-metric selector stays at chart level — primary control */}
+                <div className="flex rounded border border-gray-200 overflow-hidden text-[10px]">
+                  {METRIC_OPTIONS.map((opt) => (
+                    <button key={opt.value} type="button" onClick={() => setMetric(opt.value)}
+                      className={`px-2 py-0.5 transition-colors border-l border-gray-200 first:border-l-0
+                        ${metric === opt.value ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+                      {opt.label}
+                    </button>
+                  ))}
+                </div>
+              </div>
+              <button type="button" onClick={() => countsS.setExpanded((e) => !e)}
+                className={[
+                  'text-xs px-2 py-0.5 rounded border transition-colors',
+                  countsS.expanded
+                    ? 'bg-gray-100 border-gray-300 text-gray-700'
+                    : countsS.isDirty
+                      ? 'bg-indigo-50 border-indigo-200 text-indigo-600'
+                      : 'bg-white border-gray-200 text-gray-400 hover:text-gray-700 hover:border-gray-300',
+                ].join(' ')}>
+                {countsS.expanded ? '▲ collapse' : '▾ customize'}
+              </button>
+            </div>
+            {countsS.expanded && (
+              <ChartSettingsBar s={countsS} xAxisFields={xAxisFields} globalXField={xField} />
+            )}
+            <ResponsiveContainer width="100%" height={countsS.height}>
+              <LineChart data={countData} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+                <CartesianGrid strokeDasharray="3 3" stroke="#f3f4f6" />
+                <XAxis {...xAxisProps(countData, countsTicks, countsS, countsXLabel)} />
+                <YAxis tick={{ fontSize: 10 }} width={30} allowDecimals={false} domain={countsS.yDomain} />
+                <Tooltip content={<ExpTooltip />} />
+                <Legend wrapperStyle={{ fontSize: 11 }}
+                  formatter={(value) => lines.find((l) => l.id === value)?.name ?? value}
+                  onClick={(o) => toggleHidden(o.dataKey)}
+                  onMouseEnter={(o) => setHighlightedSubject(o.dataKey)}
+                  onMouseLeave={() => setHighlightedSubject(null)} />
+                {lines.map((l) => (
+                  <Line key={l.id} type="monotone" dataKey={l.id} name={l.id}
+                    stroke={l.color}
+                    strokeWidth={highlightedSubject === l.id ? 3.5 : 2}
+                    hide={hiddenSubjects.has(l.id)}
+                    dot={{ r: 3 }} activeDot={{ r: 5 }}
+                    connectNulls isAnimationActive={false} />
+                ))}
+              </LineChart>
+            </ResponsiveContainer>
+          </div>
+
+          {/* Chart 2 — success rate */}
+          <div>
+            <ChartHeader title="Success rate (%) — each line is one subject" isDirty={rateS.isDirty} expanded={rateS.expanded} onToggle={() => rateS.setExpanded((e) => !e)} />
+            {rateS.expanded && (
+              <ChartSettingsBar s={rateS} xAxisFields={xAxisFields} globalXField={xField} />
+            )}
+            <ResponsiveContainer width="100%" height={rateS.height}>
+              <LineChart data={rateData} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+                <CartesianGrid strokeDasharray="3 3" stroke="#f3f4f6" />
+                <XAxis {...xAxisProps(rateData, rateTicks, rateS, rateXLabel)} />
+                <YAxis tick={{ fontSize: 10 }} width={36}
+                  domain={rateS.yDomain[0] !== 'auto' || rateS.yDomain[1] !== 'auto' ? rateS.yDomain : [0, 100]}
+                  tickFormatter={(v) => `${v}%`} />
+                <Tooltip content={<ExpTooltip unit="%" />} />
+                <Legend wrapperStyle={{ fontSize: 11 }}
+                  formatter={(value) => lines.find((l) => l.id === value)?.name ?? value}
+                  onClick={(o) => toggleHidden(o.dataKey)}
+                  onMouseEnter={(o) => setHighlightedSubject(o.dataKey)}
+                  onMouseLeave={() => setHighlightedSubject(null)} />
+                {lines.map((l) => (
+                  <Line key={l.id} type="monotone" dataKey={l.id} name={l.id}
+                    stroke={l.color}
+                    strokeWidth={highlightedSubject === l.id ? 3.5 : 2}
+                    hide={hiddenSubjects.has(l.id)}
+                    dot={{ r: 3 }} activeDot={{ r: 5 }}
+                    connectNulls isAnimationActive={false} />
+                ))}
+              </LineChart>
+            </ResponsiveContainer>
+          </div>
+          </div>
+          {sidebarOpen && (
+            <SubjectSidebar
+              lines={lines}
+              hiddenSubjects={hiddenSubjects}
+              onToggleSubject={toggleHidden}
+              onToggleGroup={toggleGroup}
+              onShowAll={showAll}
+              onHighlight={setHighlightedSubject}
+            />
+          )}
+        </div>
+      )}
+    </div>
+  );
+}

frontend/src/components/AuditLogSection.jsx

@@ -36,7 +36,7 @@ const ACTION_BADGE = {
   DELETE: 'bg-red-100 text-red-800',
 };
 
-export default function AuditLogSection({ tableName, recordId }) {
+export default function AuditLogSection({ tableName, recordId, limit = 50 }) {
   const [logs, setLogs] = useState([]);
   const [total, setTotal] = useState(0);
   const [loading, setLoading] = useState(true);
@@ -46,14 +46,14 @@ export default function AuditLogSection({ tableName, recordId }) {
   useEffect(() => {
     setLoading(true);
     auditLogsApi
-      .list({ tableName, recordId, limit: 50 })
+      .list({ tableName, recordId, limit })
       .then(({ logs, total }) => {
         setLogs(logs);
         setTotal(total);
       })
       .catch((e) => setError(e.message))
       .finally(() => setLoading(false));
-  }, [tableName, recordId]);
+  }, [tableName, recordId, limit]);
 
   return (
     <section aria-label="Modification History" className="mt-8">
@@ -76,7 +76,7 @@ export default function AuditLogSection({ tableName, recordId }) {
 
       {logs.length > 0 && (
         <div className="border border-gray-200 rounded-lg overflow-hidden divide-y divide-gray-100">
-          {logs.map((log) => (
+          {logs.slice(0, limit).map((log) => (
             <div key={log.id} className="bg-white">
               <button
                 className="w-full text-left px-4 py-3 flex items-center gap-3 hover:bg-gray-50 transition-colors"
@@ -108,6 +108,12 @@ export default function AuditLogSection({ tableName, recordId }) {
           ))}
         </div>
       )}
+
+      {total > limit && (
+        <p className="mt-2 text-xs text-gray-400">
+          Showing {limit} of {total} entries — open the daily status page to see the full history.
+        </p>
+      )}
     </section>
   );
 }

frontend/src/components/CsvAnalysis.jsx

@@ -0,0 +1,744 @@
+import React, { useState, useRef, useCallback } from 'react';
+import { parseCSVHeaders, parseCSV, getUniqueNoteValues, runAnalysis, checkFrameConsecutive, computeNumericSeries } from '../lib/csvAnalysis';
+import {
+  LineChart, Line, XAxis, YAxis, CartesianGrid, Tooltip, ResponsiveContainer,
+} from 'recharts';
+import { analysesApi, dailyStatusesApi, animalsApi } from '../api/client';
+import Button from './ui/Button';
+import RunSequenceView from './RunSequenceView';
+
+// ── Constants ──────────────────────────────────────────────────────────────────
+
+const DEFAULT_BUCKETS = [
+  { name: 'Success', type: 'note', notes: [] },
+  { name: 'Failure', type: 'note', notes: [] },
+  { name: 'Other',   type: 'note', notes: [] },
+];
+const DEFAULT_BUCKET_NAMES = new Set(DEFAULT_BUCKETS.map((b) => b.name));
+
+const CATEGORY_COLORS = {
+  Success: { bg: 'bg-green-100', border: 'border-green-300', text: 'text-green-800', dot: 'bg-green-500' },
+  Failure: { bg: 'bg-red-100',   border: 'border-red-300',   text: 'text-red-800',   dot: 'bg-red-500'   },
+  Other:   { bg: 'bg-gray-100',  border: 'border-gray-300',  text: 'text-gray-700',  dot: 'bg-gray-400'  },
+};
+
+const EXTRA_COLORS = [
+  { bg: 'bg-indigo-100', border: 'border-indigo-300', text: 'text-indigo-800', dot: 'bg-indigo-500' },
+  { bg: 'bg-yellow-100', border: 'border-yellow-300', text: 'text-yellow-800', dot: 'bg-yellow-500' },
+  { bg: 'bg-purple-100', border: 'border-purple-300', text: 'text-purple-800', dot: 'bg-purple-500' },
+  { bg: 'bg-pink-100',   border: 'border-pink-300',   text: 'text-pink-800',   dot: 'bg-pink-500'   },
+  { bg: 'bg-teal-100',   border: 'border-teal-300',   text: 'text-teal-800',   dot: 'bg-teal-500'   },
+];
+
+function getCategoryColors(cat, customCategories) {
+  if (CATEGORY_COLORS[cat]) return CATEGORY_COLORS[cat];
+  const idx = customCategories.indexOf(cat) % EXTRA_COLORS.length;
+  return EXTRA_COLORS[Math.max(0, idx)];
+}
+
+// ── Sub-components ─────────────────────────────────────────────────────────────
+
+function NoteChip({ value, category, colors, selected, onSelect, draggable, onDragStart }) {
+  return (
+    <span
+      draggable={draggable}
+      onDragStart={onDragStart}
+      onClick={onSelect}
+      title={category ? `Assigned to: ${category}` : 'Unassigned — click or drag to assign'}
+      className={`
+        inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-mono font-semibold
+        border cursor-pointer select-none transition-all
+        ${colors ? `${colors.bg} ${colors.border} ${colors.text}` : 'bg-white border-gray-300 text-gray-700 hover:border-indigo-400'}
+        ${selected ? 'ring-2 ring-indigo-500 ring-offset-1' : ''}
+      `}
+    >
+      {value}
+      {category && (
+        <span className={`w-1.5 h-1.5 rounded-full ${colors?.dot}`} />
+      )}
+    </span>
+  );
+}
+
+function CategoryBucket({
+  name, type, notes, colors, isOver, isCustom, unassignedCount,
+  onDrop, onDragOver, onDragLeave, onRemoveNote, onClickAssign,
+  onBulkAddUnassigned, onRemoveBucket,
+}) {
+  return (
+    <div
+      onDragOver={(e) => { e.preventDefault(); onDragOver(); }}
+      onDragLeave={onDragLeave}
+      onDrop={(e) => { e.preventDefault(); onDrop(); }}
+      onClick={onClickAssign}
+      className={`
+        relative group rounded-lg border-2 border-dashed p-3 min-h-[80px] transition-all cursor-pointer
+        ${isOver ? `${colors.border} ${colors.bg} scale-[1.02]` : 'border-gray-200 hover:border-gray-300'}
+      `}
+    >
+      <div className="flex items-center justify-between mb-2">
+        <p className={`text-xs font-semibold uppercase tracking-wide ${colors.text}`}>
+          {name}
+          {type === 'numerical' && (
+            <span className="ml-2 text-[9px] font-bold uppercase bg-white/60 px-1 py-0.5 rounded border border-current/20">
+              numerical
+            </span>
+          )}
+        </p>
+        {isCustom && (
+          <button type="button"
+            onClick={(e) => { e.stopPropagation(); onRemoveBucket(); }}
+            className="text-[10px] text-gray-300 hover:text-red-500 opacity-0 group-hover:opacity-100 transition-opacity"
+            title="Remove this field">✕</button>
+        )}
+      </div>
+
+      {type === 'numerical' && unassignedCount > 0 && (
+        <button type="button"
+          onClick={(e) => { e.stopPropagation(); onBulkAddUnassigned(); }}
+          className={`text-[10px] mb-2 px-2 py-0.5 rounded border ${colors.border} ${colors.text} hover:bg-white transition-colors`}>
+          + Add all {unassignedCount} unassigned
+        </button>
+      )}
+
+      <div className="flex flex-wrap gap-1.5 min-h-[28px]">
+        {notes.length === 0 && (
+          <span className="text-xs text-gray-400 italic">Drop here</span>
+        )}
+        {notes.map((note) => (
+          <span key={note}
+            className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-mono font-semibold ${colors.bg} ${colors.border} ${colors.text} border`}
+          >
+            {note}
+            <button type="button" onClick={(e) => { e.stopPropagation(); onRemoveNote(note); }}
+              className="opacity-50 hover:opacity-100 leading-none">✕</button>
+          </span>
+        ))}
+      </div>
+    </div>
+  );
+}
+
+// ── Main component ─────────────────────────────────────────────────────────────
+
+export default function CsvAnalysis({ dailyStatusId, animal, onSaved, onSummaryPushed }) {
+  // Phase: 'upload' | 'columns' | 'classify' | 'results'
+  const [phase, setPhase] = useState('upload');
+
+  // Upload phase
+  const [isDragOver, setIsDragOver] = useState(false);
+  const [fileName, setFileName] = useState('');
+  const [rawText, setRawText] = useState('');
+  const [headers, setHeaders] = useState([]);
+  const fileInputRef = useRef(null);
+
+  // Columns phase
+  const [timestampCol, setTimestampCol] = useState('');
+  const [noteCol, setNoteCol] = useState('');
+  const [frameCol, setFrameCol] = useState('');
+  const [frameCheck, setFrameCheck] = useState(null);
+  const [parsePending, setParsePending] = useState(false);
+
+  // Classify phase
+  const [rows, setRows] = useState([]);
+  const [uniqueNotes, setUniqueNotes] = useState([]);
+  const [buckets, setBuckets] = useState(() => animal?.csv_analysis_config?.buckets ?? DEFAULT_BUCKETS);
+  const [selectedNote, setSelectedNote] = useState(null);
+  const [draggedNote, setDraggedNote] = useState(null);
+  const [overBucket, setOverBucket] = useState(null);
+  const [newCatName, setNewCatName] = useState('');
+  const [newCatType, setNewCatType] = useState('note');
+  const [showNewCat, setShowNewCat] = useState(false);
+
+  // Derived from buckets (recomputed every render — cheap)
+  const categories       = buckets.map((b) => b.name);
+  const customCategories = buckets.filter((b) => !DEFAULT_BUCKET_NAMES.has(b.name)).map((b) => b.name);
+  const noteBuckets      = buckets.filter((b) => b.type === 'note');
+  const numericalBuckets = buckets.filter((b) => b.type === 'numerical');
+  const classifications  = Object.fromEntries(
+    noteBuckets.flatMap((b) => b.notes.map((n) => [n, b.name]))
+  );
+
+  // Results phase
+  const [results, setResults] = useState(null);
+  const [savedAnalysisId, setSavedAnalysisId] = useState(null);
+  const [saving, setSaving] = useState(false);
+  const [saveError, setSaveError] = useState(null);
+  const [summaryPushing, setSummaryPushing] = useState(false);
+  const [summaryPushed, setSummaryPushed] = useState(false);
+  const [summaryError, setSummaryError] = useState(null);
+  const [configSaveError, setConfigSaveError] = useState(null);
+
+  // ── File reading ─────────────────────────────────────────────────────────────
+
+  function readFile(file) {
+    if (!file || !file.name.endsWith('.csv')) {
+      alert('Please upload a .csv file.');
+      return;
+    }
+    const reader = new FileReader();
+    reader.onload = (e) => {
+      const text = e.target.result;
+      const hdrs = parseCSVHeaders(text);
+      setFileName(file.name);
+      setRawText(text);
+      setHeaders(hdrs);
+      // Default columns
+      const tsDefault = hdrs.find(h => /timestamp|time/i.test(h)) ?? hdrs[0] ?? '';
+      const noteDefault = hdrs.find(h => /note|label|event/i.test(h)) ?? hdrs[hdrs.length - 1] ?? '';
+      const frameDefault = hdrs.find(h => /frame/i.test(h)) ?? '';
+      setTimestampCol(tsDefault);
+      setNoteCol(noteDefault);
+      setFrameCol(frameDefault);
+      setFrameCheck(null);
+      setPhase('columns');
+    };
+    reader.readAsText(file);
+  }
+
+  const handleDrop = useCallback((e) => {
+    e.preventDefault();
+    setIsDragOver(false);
+    readFile(e.dataTransfer.files[0]);
+  }, []);
+
+  // ── Column selection → parse data ────────────────────────────────────────────
+
+  function loadData() {
+    setParsePending(true);
+    setTimeout(() => {
+      const { rows: parsed } = parseCSV(rawText);
+      const uniq = getUniqueNoteValues(parsed, noteCol);
+      setRows(parsed);
+      setUniqueNotes(uniq);
+      setBuckets((prev) => prev.map((b) => ({ ...b, notes: [] })));
+      setSelectedNote(null);
+      if (frameCol) setFrameCheck(checkFrameConsecutive(parsed, frameCol));
+      setParsePending(false);
+      setPhase('classify');
+    }, 20);
+  }
+
+  // ── Classification helpers ───────────────────────────────────────────────────
+
+  function assign(note, category) {
+    setBuckets((prev) => prev.map((b) => {
+      if (b.name === category) {
+        return b.notes.includes(note) ? b : { ...b, notes: [...b.notes, note] };
+      }
+      // Remove from any other bucket so a note belongs to at most one
+      return b.notes.includes(note) ? { ...b, notes: b.notes.filter((n) => n !== note) } : b;
+    }));
+    setSelectedNote(null);
+  }
+
+  function unassign(note) {
+    setBuckets((prev) => prev.map((b) =>
+      b.notes.includes(note) ? { ...b, notes: b.notes.filter((n) => n !== note) } : b
+    ));
+  }
+
+  function addBucket(name, type) {
+    const trimmed = name.trim();
+    if (!trimmed || buckets.some((b) => b.name === trimmed)) return;
+    setBuckets((prev) => [...prev, { name: trimmed, type, notes: [] }]);
+  }
+
+  const unassignedNotes = uniqueNotes.filter(n => !classifications[n]);
+  const allAssigned = uniqueNotes.length > 0 && unassignedNotes.length === 0;
+
+  // ── Run analysis ─────────────────────────────────────────────────────────────
+
+  async function compute() {
+    // Note-only classifications so numerical buckets don't pollute counts/runs
+    const noteClassifications = Object.fromEntries(
+      noteBuckets.flatMap((b) => b.notes.map((n) => [n, b.name]))
+    );
+    const res = runAnalysis(rows, timestampCol, noteCol, noteClassifications);
+
+    // Numerical series — one per numerical bucket. xCol = frame if set, else timestamp.
+    const xCol = frameCol || timestampCol;
+    const numericSeries = numericalBuckets.map((b) => ({
+      bucket: b,
+      ...computeNumericSeries(rows, xCol, noteCol, b),
+    }));
+
+    setResults({ ...res, numericSeries });
+    setPhase('results');
+
+    // Persist bucket config to the animal so future uploads pre-classify.
+    // Independent of dailyStatusId — runs even for ad-hoc analyses.
+    if (animal?.id) {
+      setConfigSaveError(null);
+      animalsApi.updateCsvConfig(animal.id, { buckets })
+        .catch((err) => setConfigSaveError(err.message ?? 'Failed to save bucket config'));
+    }
+
+    if (!dailyStatusId) return;
+    setSaving(true);
+    setSaveError(null);
+    try {
+      const saved = await analysesApi.create(dailyStatusId, {
+        file_name:         fileName || null,
+        timestamp_col:     timestampCol,
+        note_col:          noteCol,
+        classifications:   noteClassifications,
+        total_note_rows:   res.totalNoteRows,
+        session_end_ts:    res.sessionEndTs,
+        sequence:          res.sequence,
+        category_counts:   res.categoryCounts,
+        consecutive_stats: res.consecutiveStats,
+        runs:              res.runs,
+      });
+      setSavedAnalysisId(saved.id);
+      onSaved?.(saved);
+    } catch (err) {
+      setSaveError(err.message ?? 'Failed to save analysis');
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  // ── Push summary to daily status ─────────────────────────────────────────────
+
+  async function pushSummary() {
+    if (!dailyStatusId || !results) return;
+    setSummaryPushing(true);
+    setSummaryPushed(false);
+    setSummaryError(null);
+    try {
+      const counts = {};
+      for (const [cat, data] of Object.entries(results.categoryCounts)) {
+        counts[cat] = data.total;
+      }
+      const total = Object.values(counts).reduce((a, b) => a + b, 0);
+      const successRate = counts['Success'] != null ? counts['Success'] / total : null;
+      await dailyStatusesApi.updateAnalysisSummary(dailyStatusId, {
+        counts,
+        total,
+        success_rate: successRate,
+        source_analysis_id: savedAnalysisId ?? null,
+      });
+      setSummaryPushed(true);
+      onSummaryPushed?.({ counts, total, success_rate: successRate });
+    } catch (err) {
+      setSummaryError(err.message ?? 'Failed to update');
+    } finally {
+      setSummaryPushing(false);
+    }
+  }
+
+  // ── Reset ────────────────────────────────────────────────────────────────────
+
+  function reset() {
+    setPhase('upload');
+    setRawText('');
+    setHeaders([]);
+    setRows([]);
+    setUniqueNotes([]);
+    setBuckets(animal?.csv_analysis_config?.buckets ?? DEFAULT_BUCKETS);
+    setResults(null);
+    setSavedAnalysisId(null);
+    setSummaryPushed(false);
+    setSummaryError(null);
+    setFrameCheck(null);
+  }
+
+  // ── Render ───────────────────────────────────────────────────────────────────
+
+  return (
+    <div className="mt-8 border-t border-gray-200 pt-6">
+      <div className="flex items-center justify-between mb-4">
+        <h2 className="text-sm font-semibold text-gray-700 uppercase tracking-wide">CSV Analysis</h2>
+        {phase !== 'upload' && (
+          <button type="button" onClick={reset} className="text-xs text-gray-400 hover:text-gray-600">
+            ✕ Start over
+          </button>
+        )}
+      </div>
+
+      {/* ── PHASE: upload ── */}
+      {phase === 'upload' && (
+        <div
+          onDragOver={(e) => { e.preventDefault(); setIsDragOver(true); }}
+          onDragLeave={() => setIsDragOver(false)}
+          onDrop={handleDrop}
+          onClick={() => fileInputRef.current?.click()}
+          className={`
+            border-2 border-dashed rounded-xl p-10 text-center cursor-pointer transition-all
+            ${isDragOver ? 'border-indigo-400 bg-indigo-50' : 'border-gray-200 hover:border-gray-300 bg-gray-50'}
+          `}
+        >
+          <input ref={fileInputRef} type="file" accept=".csv" className="hidden"
+            onChange={(e) => readFile(e.target.files[0])} />
+          <p className="text-sm text-gray-500">
+            {isDragOver ? 'Drop CSV file to upload' : 'Drop a CSV file here, or click to browse'}
+          </p>
+          <p className="text-xs text-gray-400 mt-1">Columns will be read; data stays in your browser</p>
+        </div>
+      )}
+
+      {/* ── PHASE: columns ── */}
+      {phase === 'columns' && (
+        <div className="space-y-4">
+          <p className="text-sm text-gray-600">
+            <span className="font-medium">{fileName}</span> loaded — {headers.length} columns detected. Select the columns to analyse.
+          </p>
+          <div className="grid grid-cols-2 gap-4 max-w-lg">
+            <div>
+              <label className="block text-xs font-medium text-gray-500 mb-1">Timestamp column</label>
+              <select value={timestampCol} onChange={(e) => setTimestampCol(e.target.value)}
+                className="w-full text-sm border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-indigo-400">
+                {headers.map(h => <option key={h} value={h}>{h}</option>)}
+              </select>
+            </div>
+            <div>
+              <label className="block text-xs font-medium text-gray-500 mb-1">Note column</label>
+              <select value={noteCol} onChange={(e) => setNoteCol(e.target.value)}
+                className="w-full text-sm border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-indigo-400">
+                {headers.map(h => <option key={h} value={h}>{h}</option>)}
+              </select>
+            </div>
+            <div>
+              <label className="block text-xs font-medium text-gray-500 mb-1">
+                Frame number column <span className="font-normal text-gray-400">(gap check)</span>
+              </label>
+              <select value={frameCol} onChange={(e) => setFrameCol(e.target.value)}
+                className="w-full text-sm border border-gray-300 rounded px-2 py-1.5 focus:outline-none focus:ring-2 focus:ring-indigo-400">
+                <option value="">— skip —</option>
+                {headers.map(h => <option key={h} value={h}>{h}</option>)}
+              </select>
+            </div>
+          </div>
+          <Button onClick={loadData} disabled={parsePending}>
+            {parsePending ? 'Parsing…' : 'Load note values →'}
+          </Button>
+        </div>
+      )}
+
+      {/* ── PHASE: classify ── */}
+      {phase === 'classify' && (
+        <div className="space-y-5">
+
+          {/* Frame gap check results */}
+          {frameCheck && (
+            <div className={`rounded-lg border px-3 py-2.5 text-xs ${frameCheck.consecutive ? 'bg-green-50 border-green-200 text-green-800' : 'bg-amber-50 border-amber-200 text-amber-800'}`}>
+              <p className="font-semibold mb-1">
+                Frame check ({frameCol}): {frameCheck.consecutive ? `✓ all ${frameCheck.total} frames consecutive` : `⚠ issues found in ${frameCheck.total} frames`}
+              </p>
+              {frameCheck.gaps.length > 0 && (
+                <div className="mb-1">
+                  <span className="font-medium">{frameCheck.gaps.length} gap{frameCheck.gaps.length !== 1 ? 's' : ''}:</span>
+                  <ul className="mt-0.5 space-y-0.5 max-h-32 overflow-y-auto font-mono">
+                    {frameCheck.gaps.map((g, i) => (
+                      <li key={i}>row {g.rowIndex + 1}: expected {g.expected}, got {g.actual} (jump +{g.jump})</li>
+                    ))}
+                  </ul>
+                </div>
+              )}
+              {frameCheck.duplicates.length > 0 && (
+                <div>
+                  <span className="font-medium">{frameCheck.duplicates.length} duplicate{frameCheck.duplicates.length !== 1 ? 's' : ''}:</span>
+                  <ul className="mt-0.5 space-y-0.5 font-mono max-h-20 overflow-y-auto">
+                    {frameCheck.duplicates.map((d, i) => (
+                      <li key={i}>row {d.rowIndex + 1}: frame {d.value}</li>
+                    ))}
+                  </ul>
+                </div>
+              )}
+            </div>
+          )}
+
+          <p className="text-sm text-gray-600">
+            Found <span className="font-semibold">{uniqueNotes.length}</span> unique note value{uniqueNotes.length !== 1 ? 's' : ''}.
+            {selectedNote && (
+              <span className="ml-2 text-indigo-600 font-medium">
+                Selected: <span className="font-mono">{selectedNote}</span> — click a category to assign
+              </span>
+            )}
+          </p>
+
+          {/* Unassigned chips */}
+          {unassignedNotes.length > 0 && (
+            <div>
+              <p className="text-xs font-semibold text-gray-400 uppercase tracking-wide mb-1.5">Unassigned</p>
+              <div className="flex flex-wrap gap-2">
+                {unassignedNotes.map(note => (
+                  <NoteChip key={note} value={note} category={null} colors={null}
+                    selected={selectedNote === note}
+                    onSelect={() => setSelectedNote(prev => prev === note ? null : note)}
+                    draggable onDragStart={() => setDraggedNote(note)}
+                  />
+                ))}
+              </div>
+            </div>
+          )}
+
+          {/* Category buckets */}
+          <div className="grid grid-cols-3 gap-3">
+            {buckets.map((b) => {
+              const colors = getCategoryColors(b.name, customCategories);
+              const isCustom = !DEFAULT_BUCKET_NAMES.has(b.name);
+              return (
+                <CategoryBucket key={b.name} name={b.name} type={b.type} notes={b.notes} colors={colors}
+                  isOver={overBucket === b.name}
+                  isCustom={isCustom}
+                  unassignedCount={unassignedNotes.length}
+                  onDragOver={() => setOverBucket(b.name)}
+                  onDragLeave={() => setOverBucket(null)}
+                  onDrop={() => {
+                    if (draggedNote) { assign(draggedNote, b.name); setDraggedNote(null); setOverBucket(null); }
+                  }}
+                  onClickAssign={() => { if (selectedNote) assign(selectedNote, b.name); }}
+                  onRemoveNote={(note) => unassign(note)}
+                  onBulkAddUnassigned={() => {
+                    for (const n of unassignedNotes) assign(n, b.name);
+                  }}
+                  onRemoveBucket={() => setBuckets((prev) => prev.filter((x) => x.name !== b.name))}
+                />
+              );
+            })}
+          </div>
+
+          {/* Add new bucket — note or numerical */}
+          <div className="flex items-center gap-2 flex-wrap">
+            {showNewCat ? (
+              <>
+                <input
+                  autoFocus
+                  value={newCatName}
+                  onChange={(e) => setNewCatName(e.target.value)}
+                  onKeyDown={(e) => { if (e.key === 'Escape') setShowNewCat(false); }}
+                  placeholder="Field name…"
+                  className="text-sm border border-gray-300 rounded px-2 py-1 focus:outline-none focus:ring-2 focus:ring-indigo-400 w-40"
+                />
+                <label className="text-xs text-gray-600 inline-flex items-center gap-1">
+                  <input type="radio" name="newBucketType" value="note"
+                    checked={newCatType === 'note'}
+                    onChange={() => setNewCatType('note')} /> Note
+                </label>
+                <label className="text-xs text-gray-600 inline-flex items-center gap-1">
+                  <input type="radio" name="newBucketType" value="numerical"
+                    checked={newCatType === 'numerical'}
+                    onChange={() => setNewCatType('numerical')} /> Numerical
+                </label>
+                <Button size="sm" type="button" onClick={() => {
+                  addBucket(newCatName, newCatType);
+                  setNewCatName('');
+                  setNewCatType('note');
+                  setShowNewCat(false);
+                }}>Add</Button>
+                <button type="button" onClick={() => setShowNewCat(false)}
+                  className="text-xs text-gray-400 hover:text-gray-600">Cancel</button>
+              </>
+            ) : (
+              <button type="button" onClick={() => setShowNewCat(true)}
+                className="text-xs text-indigo-500 hover:text-indigo-700 border border-dashed border-indigo-300 rounded-full px-3 py-0.5 hover:border-indigo-500 transition-colors">
+                + Add field
+              </button>
+            )}
+          </div>
+
+          {/* Unclassified warning */}
+          {!allAssigned && uniqueNotes.length > 0 && (
+            <p className="text-xs text-amber-600 bg-amber-50 border border-amber-200 rounded px-3 py-1.5">
+              {unassignedNotes.length} unassigned note value{unassignedNotes.length !== 1 ? 's' : ''} will be excluded from the analysis.
+            </p>
+          )}
+
+          <Button onClick={compute} disabled={uniqueNotes.length === 0}>
+            Run analysis →
+          </Button>
+        </div>
+      )}
+
+      {/* ── PHASE: results ── */}
+      {phase === 'results' && results && (
+        <div className="space-y-6">
+          <div className="flex items-center justify-between">
+            <p className="text-sm text-gray-500">
+              Analysed <span className="font-semibold">{results.totalNoteRows}</span> note rows
+              · columns: <span className="font-mono text-xs">{timestampCol}</span> / <span className="font-mono text-xs">{noteCol}</span>
+            </p>
+            {dailyStatusId && (
+              <span className="text-xs">
+                {saving && <span className="text-gray-400">Saving…</span>}
+                {!saving && !saveError && results && <span className="text-green-600">✓ Saved</span>}
+                {saveError && <span className="text-red-500" title={saveError}>⚠ Save failed</span>}
+              </span>
+            )}
+          </div>
+
+          {/* Category counts */}
+          <div>
+            <h3 className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-2">Category Counts</h3>
+            <table className="w-full text-sm border-collapse">
+              <thead>
+                <tr className="bg-gray-50 border-b border-gray-200">
+                  <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Category</th>
+                  <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Note breakdown</th>
+                  <th className="text-right px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Total</th>
+                </tr>
+              </thead>
+              <tbody>
+                {Object.entries(results.categoryCounts)
+                  .sort(([, a], [, b]) => b.total - a.total)
+                  .map(([cat, data]) => {
+                    const colors = getCategoryColors(cat, customCategories);
+                    const breakdown = Object.entries(data.byNote)
+                      .sort(([, a], [, b]) => b - a)
+                      .map(([n, c]) => `${n}: ${c}`)
+                      .join(' · ');
+                    return (
+                      <tr key={cat} className="border-b border-gray-100">
+                        <td className="px-3 py-2">
+                          <span className={`inline-flex items-center gap-1.5 px-2 py-0.5 rounded-full text-xs font-semibold ${colors.bg} ${colors.text}`}>
+                            <span className={`w-1.5 h-1.5 rounded-full ${colors.dot}`} />
+                            {cat}
+                          </span>
+                        </td>
+                        <td className="px-3 py-2 text-gray-500 font-mono text-xs">{breakdown}</td>
+                        <td className="px-3 py-2 text-right font-semibold text-gray-800">{data.total}</td>
+                      </tr>
+                    );
+                  })}
+                {Object.keys(results.categoryCounts).length === 0 && (
+                  <tr><td colSpan={3} className="px-3 py-4 text-center text-gray-400 italic text-sm">No classified notes</td></tr>
+                )}
+              </tbody>
+            </table>
+          </div>
+
+          {/* Consecutive stats */}
+          {Object.keys(results.consecutiveStats).length > 0 && (
+            <div>
+              <h3 className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-2">Consecutive Runs</h3>
+              <p className="text-xs text-gray-400 mb-2">
+                How many times each category appeared in a row (run-length encoding of the category sequence, ordered by timestamp).
+              </p>
+              <table className="w-full text-sm border-collapse">
+                <thead>
+                  <tr className="bg-gray-50 border-b border-gray-200">
+                    <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Category</th>
+                    <th className="text-right px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Total runs</th>
+                    <th className="text-right px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Max run</th>
+                    <th className="text-right px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Avg run</th>
+                    <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide">Run lengths</th>
+                  </tr>
+                </thead>
+                <tbody>
+                  {Object.entries(results.consecutiveStats)
+                    .sort(([, a], [, b]) => b.totalRuns - a.totalRuns)
+                    .map(([cat, s]) => {
+                      const colors = getCategoryColors(cat, customCategories);
+                      const runSummary = s.runLengths
+                        .reduce((acc, len) => {
+                          acc[len] = (acc[len] || 0) + 1;
+                          return acc;
+                        }, {});
+                      const runDisplay = Object.entries(runSummary)
+                        .sort(([a], [b]) => Number(a) - Number(b))
+                        .map(([len, cnt]) => `${len}×${cnt}`)
+                        .join(', ');
+                      return (
+                        <tr key={cat} className="border-b border-gray-100">
+                          <td className="px-3 py-2">
+                            <span className={`inline-flex items-center gap-1.5 px-2 py-0.5 rounded-full text-xs font-semibold ${colors.bg} ${colors.text}`}>
+                              <span className={`w-1.5 h-1.5 rounded-full ${colors.dot}`} />
+                              {cat}
+                            </span>
+                          </td>
+                          <td className="px-3 py-2 text-right text-gray-700">{s.totalRuns}</td>
+                          <td className="px-3 py-2 text-right text-gray-700">{s.maxRun}</td>
+                          <td className="px-3 py-2 text-right text-gray-700">{s.avgRun.toFixed(2)}</td>
+                          <td className="px-3 py-2 text-gray-500 font-mono text-xs">{runDisplay}</td>
+                        </tr>
+                      );
+                    })}
+                </tbody>
+              </table>
+            </div>
+          )}
+
+          <RunSequenceView
+            runs={results.runs}
+            sequence={results.sequence}
+            customCategories={customCategories}
+            sessionEndTs={results.sessionEndTs}
+          />
+
+          {/* Numerical plots — one panel per numerical bucket */}
+          {results.numericSeries && results.numericSeries.length > 0 && (
+            <div>
+              <h3 className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-2">Numerical Plots</h3>
+              <div className="space-y-4">
+                {results.numericSeries.map(({ bucket, points, avg, skipped, total, xLabel }) => {
+                  const colors = getCategoryColors(bucket.name, customCategories);
+                  return (
+                    <div key={bucket.name} className="border border-gray-200 rounded-lg p-3">
+                      <div className="flex items-baseline justify-between mb-2">
+                        <p className={`text-sm font-semibold ${colors.text}`}>
+                          {bucket.name} <span className="text-xs text-gray-400 font-normal">vs {xLabel}</span>
+                        </p>
+                        <p className="text-xs text-gray-500">
+                          {avg != null ? <>Avg: <strong className="text-gray-800">{avg.toFixed(2)}</strong> · </> : null}
+                          {points.length}/{total} rows plottable
+                          {skipped > 0 && <> · {skipped} skipped</>}
+                        </p>
+                      </div>
+                      {points.length > 0 ? (
+                        <ResponsiveContainer width="100%" height={220}>
+                          <LineChart data={points} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+                            <CartesianGrid strokeDasharray="3 3" stroke="#eee" />
+                            <XAxis dataKey="x" type="number" domain={['dataMin', 'dataMax']}
+                              tick={{ fontSize: 10 }} label={{ value: xLabel, position: 'insideBottom', offset: -2, fontSize: 10 }} />
+                            <YAxis tick={{ fontSize: 10 }} />
+                            <Tooltip />
+                            <Line type="monotone" dataKey="value" stroke="currentColor" className={colors.text}
+                              dot={{ r: 2 }} strokeWidth={2} />
+                          </LineChart>
+                        </ResponsiveContainer>
+                      ) : (
+                        <p className="text-xs text-gray-400 italic">
+                          No plottable values — {total} of {total} note rows had no extractable number.
+                        </p>
+                      )}
+                    </div>
+                  );
+                })}
+              </div>
+            </div>
+          )}
+
+          {/* Save metrics to daily status */}
+          {dailyStatusId && (
+            <div className="pt-3 border-t border-gray-100">
+              <div className="flex items-center gap-3 flex-wrap">
+                <button type="button" onClick={pushSummary} disabled={summaryPushing}
+                  className="inline-flex items-center gap-1.5 px-3 py-1.5 rounded-lg text-sm font-medium bg-indigo-600 text-white hover:bg-indigo-700 disabled:opacity-50 transition-colors">
+                  {summaryPushing ? 'Saving…' : summaryPushed ? '✓ Metrics saved to daily status' : 'Save metrics to daily status'}
+                </button>
+                {summaryError && <span className="text-xs text-red-500">{summaryError}</span>}
+              </div>
+              {!summaryPushed && (
+                <p className="text-[10px] text-gray-400 mt-1">
+                  Saves success / failure counts, total attempts, and success rate to this day's record for cross-day and cross-subject graphing.
+                </p>
+              )}
+            </div>
+          )}
+
+          {configSaveError && (
+            <p className="text-xs text-amber-600 bg-amber-50 border border-amber-200 rounded px-3 py-1.5">
+              Bucket config didn't save: {configSaveError}. Analysis still ran. Try running again to retry.
+            </p>
+          )}
+          <div className="flex gap-3 pt-2 border-t border-gray-100">
+            <Button variant="secondary" onClick={() => setPhase('classify')}>← Reclassify</Button>
+            <Button variant="secondary" onClick={reset}>Start over</Button>
+          </div>
+        </div>
+      )}
+    </div>
+  );
+}

frontend/src/components/DailyStatusForm.jsx

@@ -1,68 +1,132 @@
 import React, { useState, useEffect } from 'react';
 import { format } from 'date-fns';
 import Button from './ui/Button';
-import FormField, { Input, Textarea } from './ui/FormField';
+import { Input, Textarea } from './ui/FormField';
 import Alert from './ui/Alert';
-import { dailyStatusesApi } from '../api/client';
+import { dailyStatusesApi, experimentsApi } from '../api/client';
 
-export default function DailyStatusForm({ existing, animalId, onSuccess, onCancel }) {
+const BUILTIN_KEYS = new Set(['experiment_description', 'vitals', 'treatment', 'notes']);
+const EMPTY_TEMPLATE = [];
+
+// Maps field width % to a 12-column grid span
+function widthToSpan(pct) {
+  if (pct <= 8)  return 1;
+  if (pct <= 17) return 2;
+  if (pct <= 25) return 3;
+  if (pct <= 33) return 4;
+  if (pct <= 42) return 5;
+  if (pct <= 50) return 6;
+  if (pct <= 67) return 8;
+  if (pct <= 75) return 9;
+  return 12;
+}
+
+/** Extract the value for a field from a status record.
+ *  Custom fields are keyed by fieldId (stable UUID), not by key (display slug). */
+function getValue(status, field) {
+  if (!status) return '';
+  if (field.builtin) return status[field.key] ?? '';
+  return status.custom_fields?.[field.fieldId] ?? '';
+}
+
+export default function DailyStatusForm({ existing, animalId, experimentId, template = EMPTY_TEMPLATE, onTemplateUpdate, onSuccess, onCancel, onRequestDelete, hasPrev, hasNext, onNavigate }) {
   const today = format(new Date(), 'yyyy-MM-dd');
-  const [fields, setFields] = useState({
-    date: existing ? format(new Date(existing.date), 'yyyy-MM-dd') : today,
-    experiment_description: existing?.experiment_description ?? '',
-    vitals: existing?.vitals ?? '',
-    treatment: existing?.treatment ?? '',
-    notes: existing?.notes ?? '',
-  });
+
+  // Active fields from template (date is always first and handled separately)
+  const activeFields = template.filter((f) => f.active);
+
+  function buildInitialValues() {
+    const vals = { date: existing ? String(existing.date).slice(0, 10) : today };
+    for (const f of activeFields) {
+      vals[f.key] = getValue(existing, f);
+    }
+    return vals;
+  }
+
+  const [values, setValues] = useState(buildInitialValues);
   const [errors, setErrors] = useState({});
   const [apiError, setApiError] = useState(null);
   const [loading, setLoading] = useState(false);
+  const [savingTagFor, setSavingTagFor] = useState(null); // fieldId currently being saved
 
   useEffect(() => {
-    setFields({
-      date: existing ? format(new Date(existing.date), 'yyyy-MM-dd') : today,
-      experiment_description: existing?.experiment_description ?? '',
-      vitals: existing?.vitals ?? '',
-      treatment: existing?.treatment ?? '',
-      notes: existing?.notes ?? '',
-    });
+    setValues(buildInitialValues());
     setErrors({});
     setApiError(null);
-  }, [existing]);
+  }, [existing, template]);
 
-  const set = (k) => (e) => setFields((f) => ({ ...f, [k]: e.target.value }));
+  const set = (key) => (e) => setValues((v) => ({ ...v, [key]: e.target.value }));
+
+  async function saveTag(field) {
+    const value = (values[field.key] ?? '').trim();
+    if (!value || !experimentId || !onTemplateUpdate) return;
+    setSavingTagFor(field.fieldId);
+    try {
+      const updatedTemplate = template.map((f) =>
+        f.fieldId === field.fieldId
+          ? { ...f, tags: [...(f.tags ?? []), value] }
+          : f
+      );
+      await experimentsApi.updateTemplate(experimentId, updatedTemplate);
+      onTemplateUpdate(updatedTemplate);
+    } catch (err) {
+      // non-critical — silently ignore tag save errors
+    } finally {
+      setSavingTagFor(null);
+    }
+  }
 
   function validate() {
     const e = {};
-    if (!fields.date) {
+    if (!values.date) {
       e.date = 'Date is required';
-    } else if (!/^\d{4}-\d{2}-\d{2}$/.test(fields.date)) {
-      e.date = 'Date must be in YYYY-MM-DD format';
-    } else {
-      const d = new Date(fields.date);
-      if (isNaN(d.getTime())) e.date = 'Invalid date';
+    } else if (!/^\d{4}-\d{2}-\d{2}$/.test(values.date) || isNaN(new Date(values.date).getTime())) {
+      e.date = 'Date must be a valid YYYY-MM-DD date';
     }
     setErrors(e);
     return Object.keys(e).length === 0;
   }
 
+  async function doSave() {
+    const builtin = {};
+    const custom = {};
+    for (const f of activeFields) {
+      const val = values[f.key] || null;
+      if (f.builtin) {
+        builtin[f.key] = val;
+      } else {
+        custom[f.fieldId] = val;
+      }
+    }
+    const existingCustom = existing?.custom_fields ?? {};
+    const mergedCustom = { ...existingCustom, ...custom };
+    const payload = { date: values.date, ...builtin, custom_fields: mergedCustom };
+    return existing
+      ? await dailyStatusesApi.update(existing.id, payload)
+      : await dailyStatusesApi.create({ ...payload, animal_id: animalId });
+  }
+
   async function handleSubmit(e) {
     e.preventDefault();
     if (!validate()) return;
     setLoading(true);
     setApiError(null);
     try {
-      const payload = {
-        date: fields.date,
-        experiment_description: fields.experiment_description || null,
-        vitals: fields.vitals || null,
-        treatment: fields.treatment || null,
-        notes: fields.notes || null,
-      };
-      const result = existing
-        ? await dailyStatusesApi.update(existing.id, payload)
-        : await dailyStatusesApi.create({ ...payload, animal_id: animalId });
-      onSuccess(result);
+      onSuccess(await doSave());
+    } catch (err) {
+      setApiError(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  async function handleNavigate(direction) {
+    if (!validate()) return;
+    setLoading(true);
+    setApiError(null);
+    try {
+      const result = await doSave();
+      onNavigate(direction, result);
     } catch (err) {
       setApiError(err);
     } finally {
@@ -71,68 +135,93 @@ export default function DailyStatusForm({ existing, animalId, onSuccess, onCance
   }
 
   return (
-    <form onSubmit={handleSubmit} noValidate className="space-y-4">
+    <form onSubmit={handleSubmit} noValidate>
       {apiError && (
-        <Alert
-          type="error"
-          message={apiError.message}
-          details={apiError.details}
-          onDismiss={() => setApiError(null)}
-        />
+        <Alert type="error" message={apiError.message} details={apiError.details} onDismiss={() => setApiError(null)} />
       )}
-      <FormField label="Date" name="date" error={errors.date} required>
-        <Input
-          type="date"
-          name="date"
-          value={fields.date}
-          onChange={set('date')}
-          required
-          disabled={loading}
-        />
-      </FormField>
-      <FormField label="Experiment Description" name="experiment_description">
-        <Textarea
-          name="experiment_description"
-          value={fields.experiment_description}
-          onChange={set('experiment_description')}
-          placeholder="Describe the experimental conditions…"
-          disabled={loading}
-        />
-      </FormField>
-      <FormField label="Vitals" name="vitals">
-        <Input
-          name="vitals"
-          value={fields.vitals}
-          onChange={set('vitals')}
-          placeholder="e.g. HR 72bpm, Temp 37.2°C, Weight 280g"
-          disabled={loading}
-        />
-      </FormField>
-      <FormField label="Treatment" name="treatment">
-        <Input
-          name="treatment"
-          value={fields.treatment}
-          onChange={set('treatment')}
-          placeholder="e.g. Drug X — 10mg/kg oral"
-          disabled={loading}
-        />
-      </FormField>
-      <FormField label="Notes" name="notes">
-        <Textarea
-          name="notes"
-          value={fields.notes}
-          onChange={set('notes')}
-          placeholder="Any additional observations…"
-          disabled={loading}
-        />
-      </FormField>
-      <div className="flex justify-end gap-3 pt-2">
-        <Button variant="secondary" type="button" onClick={onCancel} disabled={loading}>
-          Cancel
-        </Button>
-        <Button type="submit" loading={loading}>
-          {existing ? 'Save Changes' : 'Log Status'}
-        </Button>
+
+      <div className="grid grid-cols-12 gap-x-3 gap-y-2 mb-4">
+        {/* Date — always full width */}
+        <div className="col-span-12 flex items-center gap-2">
+          <label htmlFor="date" className="text-xs font-medium text-gray-500 whitespace-nowrap w-28 shrink-0 text-right">Date <span className="text-red-400">*</span></label>
+          <div className="w-36">
+            <Input type="date" name="date" value={values.date} onChange={set('date')} required disabled={loading} />
+            {errors.date && <p role="alert" className="text-xs text-red-500 mt-0.5">{errors.date}</p>}
+          </div>
+        </div>
+
+        {/* Dynamic fields */}
+        {activeFields.map((field) => {
+          const isTextarea = field.type === 'textarea';
+          const span = isTextarea ? 12 : widthToSpan(field.width ?? 100);
+          const fieldTags = field.tags ?? [];
+          const currentValue = (values[field.key] ?? '').trim();
+          const canSaveTag = experimentId && onTemplateUpdate && currentValue && !fieldTags.includes(currentValue) && !field.tagsDisabled;
+          return (
+            <div key={field.key} className={`col-span-${span} flex items-start gap-2`}>
+              <label htmlFor={field.key} className="text-xs font-medium text-gray-500 whitespace-nowrap w-28 shrink-0 text-right pt-1.5" title={field.label}>
+                {field.abbr || field.label}{field.unit ? <span className="font-normal text-gray-400"> ({field.unit})</span> : null}
+              </label>
+              <div className="flex-1 min-w-0">
+                {isTextarea ? (
+                  <Textarea name={field.key} value={values[field.key] ?? ''} onChange={set(field.key)} disabled={loading} />
+                ) : (
+                  <Input name={field.key} value={values[field.key] ?? ''} onChange={set(field.key)} disabled={loading} />
+                )}
+                {(fieldTags.length > 0 || canSaveTag) && (
+                  <div className="flex flex-wrap items-center gap-1.5 mt-1">
+                    {fieldTags.map((tag) => (
+                      <button key={tag} type="button" title={`Quick-fill: ${tag}`}
+                        onClick={() => setValues((v) => ({ ...v, [field.key]: tag }))}
+                        className="inline-flex items-center px-2 py-0.5 rounded-full bg-indigo-50 border border-indigo-200 text-indigo-700 text-xs font-medium hover:bg-indigo-100 transition-colors">
+                        {tag}
+                      </button>
+                    ))}
+                    {canSaveTag && (
+                      <button type="button" onClick={() => saveTag(field)} disabled={savingTagFor === field.fieldId}
+                        title="Save current value as a quick-fill tag"
+                        className="inline-flex items-center gap-1 px-2 py-0.5 rounded-full border border-dashed border-indigo-300 text-indigo-500 text-xs hover:border-indigo-500 hover:text-indigo-700 transition-colors disabled:opacity-50">
+                        {savingTagFor === field.fieldId ? '…' : '+ Save as tag'}
+                      </button>
+                    )}
+                  </div>
+                )}
+              </div>
+            </div>
+          );
+        })}
+      </div>
+
+      {activeFields.length === 0 && (
+        <p className="text-sm text-gray-400 italic text-center py-2">
+          No fields configured. Edit the experiment's Record Template to add fields.
+        </p>
+      )}
+
+      <div className="flex items-center justify-between pt-2 border-t border-gray-100">
+        <div>
+          {existing && onRequestDelete && (
+            <Button variant="danger" type="button" onClick={onRequestDelete} disabled={loading}>Delete entry</Button>
+          )}
+        </div>
+        <div className="flex items-center gap-3">
+          {existing && onNavigate && (
+            <div className="flex gap-1">
+              <button type="button" onClick={() => handleNavigate('prev')} disabled={loading || !hasPrev}
+                title="Save & go to previous entry"
+                className="px-2 py-1 rounded border border-gray-300 text-gray-500 text-sm hover:bg-gray-50 disabled:opacity-30 disabled:cursor-not-allowed transition-colors">
+                ←
+              </button>
+              <button type="button" onClick={() => handleNavigate('next')} disabled={loading || !hasNext}
+                title="Save & go to next entry"
+                className="px-2 py-1 rounded border border-gray-300 text-gray-500 text-sm hover:bg-gray-50 disabled:opacity-30 disabled:cursor-not-allowed transition-colors">
+                →
+              </button>
+            </div>
+          )}
+          <Button variant="secondary" type="button" onClick={onCancel} disabled={loading}>Cancel</Button>
+          <Button type="submit" loading={loading}>{existing ? 'Save Changes' : 'Log Status'}</Button>
+        </div>
       </div>
     </form>
   );

frontend/src/components/ExperimentCalendar.jsx

@@ -0,0 +1,99 @@
+import React, { useState, useEffect, useMemo } from 'react';
+import {
+  format, startOfMonth, endOfMonth, eachDayOfInterval,
+  getDay, addMonths, subMonths,
+} from 'date-fns';
+import { useNavigate } from 'react-router-dom';
+import { experimentsApi } from '../api/client';
+
+export default function ExperimentCalendar({ experimentId, template }) {
+  const navigate = useNavigate();
+  const [currentMonth, setCurrentMonth] = useState(() => new Date());
+  const [selectedField, setSelectedField] = useState(null);
+  const [calendarDays, setCalendarDays] = useState({});
+
+  const fieldOptions = useMemo(
+    () => template.filter((f) => f.active).map((f) => ({ value: f.builtin ? f.key : f.fieldId, label: f.label })),
+    [template],
+  );
+
+  useEffect(() => {
+    if (fieldOptions.length === 0 || selectedField) return;
+    const weightField = fieldOptions.find((f) => f.label.toLowerCase().includes('weight'));
+    setSelectedField(weightField ? weightField.value : fieldOptions[0]?.value ?? null);
+  }, [fieldOptions]); // eslint-disable-line react-hooks/exhaustive-deps
+
+  useEffect(() => {
+    if (!selectedField) return;
+    let cancelled = false;
+    experimentsApi.getCalendar(experimentId, selectedField)
+      .then(({ days }) => { if (!cancelled) setCalendarDays(days); })
+      .catch(() => {});
+    return () => { cancelled = true; };
+  }, [experimentId, selectedField]);
+
+  const monthStart = startOfMonth(currentMonth);
+  const monthEnd   = endOfMonth(currentMonth);
+  const days       = eachDayOfInterval({ start: monthStart, end: monthEnd });
+  const leadingPad = getDay(monthStart);
+
+  return (
+    <div className="bg-white rounded-xl border border-gray-200 p-5 shadow-sm mt-6">
+      <h3 className="text-base font-semibold text-gray-900 mb-4">Daily Record Calendar</h3>
+
+      <div className="flex flex-wrap items-center gap-3 mb-5">
+        <span className="text-sm text-gray-600 font-medium">Count by field:</span>
+        <select
+          data-testid="field-select"
+          className="text-sm border border-gray-300 rounded-lg px-3 py-1.5 focus:outline-none focus:ring-2 focus:ring-blue-500 bg-white"
+          value={selectedField ?? ''}
+          onChange={(e) => setSelectedField(e.target.value)}
+          disabled={fieldOptions.length === 0}
+        >
+          {fieldOptions.map((f) => <option key={f.value} value={f.value}>{f.label}</option>)}
+          {fieldOptions.length === 0 && <option value="">No fields configured</option>}
+        </select>
+      </div>
+
+      <div className="flex items-center justify-between mb-4">
+        <button aria-label="Previous month" onClick={() => setCurrentMonth((m) => subMonths(m, 1))}
+          className="p-2 rounded-lg hover:bg-gray-100 text-gray-500 text-lg leading-none">&#8249;</button>
+        <span className="font-semibold text-gray-900 text-base">{format(currentMonth, 'MMMM yyyy')}</span>
+        <button aria-label="Next month" onClick={() => setCurrentMonth((m) => addMonths(m, 1))}
+          className="p-2 rounded-lg hover:bg-gray-100 text-gray-500 text-lg leading-none">&#8250;</button>
+      </div>
+
+      <div className="grid grid-cols-7 mb-1">
+        {['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'].map((d) => (
+          <div key={d} className="text-center text-xs font-medium text-gray-400 py-1 select-none">{d}</div>
+        ))}
+      </div>
+
+      <div className="grid grid-cols-7 gap-1">
+        {Array.from({ length: leadingPad }).map((_, i) => <div key={`pad-${i}`} />)}
+        {days.map((day) => {
+          const dateStr = format(day, 'yyyy-MM-dd');
+          const count   = calendarDays[dateStr] ?? 0;
+          const hasData = count > 0;
+          return (
+            <button
+              key={dateStr}
+              data-testid={`day-${dateStr}`}
+              disabled={!hasData}
+              onClick={() => navigate(`/experiments/${experimentId}/day/${dateStr}${selectedField ? `?field=${selectedField}` : ''}`)}
+              className={[
+                'relative flex flex-col items-center justify-center rounded-lg py-1.5 min-h-[2.75rem] text-sm select-none transition-all',
+                hasData ? 'bg-blue-50 border border-blue-200 hover:bg-blue-100 cursor-pointer' : 'text-gray-300 cursor-default',
+              ].join(' ')}
+            >
+              <span className={hasData ? 'font-semibold text-blue-900 text-xs' : 'text-xs'}>{day.getDate()}</span>
+              {hasData && (
+                <span data-testid={`count-${dateStr}`} className="text-[10px] leading-none font-bold text-blue-600 mt-0.5">{count}</span>
+              )}
+            </button>
+          );
+        })}
+      </div>
+    </div>
+  );
+}

frontend/src/components/ExportDataModal.jsx

@@ -0,0 +1,140 @@
+import React, { useEffect, useMemo, useState } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+import { listExportableParams, buildSubjectSeriesMatrix, toCSV, csvFilename } from '../lib/dataExport';
+
+const PARAM_GROUP_LABELS = { metrics: 'Session metrics', daily: 'Daily record fields' };
+
+function triggerDownload(filename, text) {
+  const blob = new Blob([text], { type: 'text/csv;charset=utf-8;' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url;
+  a.download = filename;
+  document.body.appendChild(a);
+  a.click();
+  document.body.removeChild(a);
+  setTimeout(() => URL.revokeObjectURL(url), 0);
+}
+
+export default function ExportDataModal({
+  experimentTitle, experimentId, dailyTemplate, animals, subjectTemplate = [], groupField = '__none__', onClose,
+}) {
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [statuses, setStatuses] = useState([]);
+
+  const [xField, setXField] = useState('__date__');
+  const [dataId, setDataId] = useState(null);
+  const [groupBy, setGroupBy] = useState(() => {
+    const valid = groupField === '__none__' || groupField === '__name__' || groupField === '__id__'
+      || subjectTemplate.some((f) => f.active && f.fieldId === groupField);
+    return valid ? groupField : '__none__';
+  });
+
+  useEffect(() => {
+    let alive = true;
+    setLoading(true);
+    setError(null);
+    experimentsApi.getDailyStatuses(experimentId, {})
+      .then((data) => { if (alive) setStatuses(data); })
+      .catch((err) => { if (alive) setError(err.message); })
+      .finally(() => { if (alive) setLoading(false); });
+    return () => { alive = false; };
+  }, [experimentId]);
+
+  const params = useMemo(() => listExportableParams(dailyTemplate ?? [], statuses), [dailyTemplate, statuses]);
+  const effDataId = dataId ?? params[0]?.id ?? null;
+  const dataParam = params.find((p) => p.id === effDataId) ?? params[0] ?? null;
+
+  const activeDaily = useMemo(() => (dailyTemplate ?? []).filter((f) => f.active), [dailyTemplate]);
+  const xOptions = useMemo(() => [
+    { id: '__date__', label: 'Date' },
+    { id: '__days__', label: '# Days Reach (ordinal)' },
+    ...activeDaily.map((f) => ({ id: f.fieldId, label: f.label })),
+  ], [activeDaily]);
+
+  const matrix = useMemo(
+    () => (dataParam
+      ? buildSubjectSeriesMatrix({ xField, dataParam, groupField: groupBy }, { statuses, animals, dailyTemplate })
+      : { columns: [], rows: [], context: { label: 'Data', value: '' }, corner: '', groupAxis: null }),
+    [xField, dataParam, groupBy, statuses, animals, dailyTemplate],
+  );
+  const hasData = matrix.rows.length > 0;
+
+  const groupedParams = useMemo(() => {
+    const out = [];
+    for (const p of params) {
+      let g = out.find((x) => x.group === p.group);
+      if (!g) { g = { group: p.group, items: [] }; out.push(g); }
+      g.items.push(p);
+    }
+    return out;
+  }, [params]);
+
+  function handleExport() {
+    if (!hasData || !dataParam) return;
+    triggerDownload(csvFilename(experimentTitle, dataParam.label), toCSV(matrix));
+    onClose();
+  }
+
+  if (loading) return <p className="text-sm text-gray-400" aria-live="polite">Loading data…</p>;
+  if (error) return (
+    <div className="space-y-4">
+      <Alert type="error" message={error} />
+      <div className="flex justify-end"><Button variant="secondary" onClick={onClose}>Close</Button></div>
+    </div>
+  );
+
+  const selectCls = 'w-full border border-gray-200 rounded px-2 py-1.5 text-sm bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400';
+
+  return (
+    <div className="space-y-4">
+      <p className="text-sm text-gray-500">
+        One value per subject over an X axis — each column is a subject, each row an X value. Blank where a subject has no value.
+      </p>
+
+      <div>
+        <label htmlFor="export-x" className="block text-xs font-medium text-gray-500 mb-1">X axis (rows)</label>
+        <select id="export-x" value={xField} onChange={(e) => setXField(e.target.value)} className={selectCls}>
+          {xOptions.map((o) => <option key={o.id} value={o.id}>{o.label}</option>)}
+        </select>
+      </div>
+
+      <div>
+        <label htmlFor="export-data" className="block text-xs font-medium text-gray-500 mb-1">Data (cells)</label>
+        <select id="export-data" value={effDataId ?? ''} onChange={(e) => setDataId(e.target.value)} className={selectCls}>
+          {groupedParams.map((g) => (
+            <optgroup key={g.group} label={PARAM_GROUP_LABELS[g.group] ?? g.group}>
+              {g.items.map((p) => <option key={p.id} value={p.id}>{p.label}</option>)}
+            </optgroup>
+          ))}
+        </select>
+      </div>
+
+      <div>
+        <label htmlFor="export-group" className="block text-xs font-medium text-gray-500 mb-1">Group by</label>
+        <select id="export-group" value={groupBy} onChange={(e) => setGroupBy(e.target.value)} className={selectCls}>
+          <option value="__none__">— None —</option>
+          <option value="__name__">Name</option>
+          <option value="__id__">Subject ID</option>
+          {subjectTemplate.filter((f) => f.active).map((f) => (
+            <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+          ))}
+        </select>
+      </div>
+
+      <p className="text-xs text-gray-400">
+        {hasData
+          ? `${matrix.rows.length} row${matrix.rows.length !== 1 ? 's' : ''} × ${matrix.columns.length} subject${matrix.columns.length !== 1 ? 's' : ''}`
+          : 'No data for this selection yet.'}
+      </p>
+
+      <div className="flex justify-end gap-2 pt-2">
+        <Button variant="secondary" onClick={onClose}>Cancel</Button>
+        <Button onClick={handleExport} disabled={!hasData}>Export CSV</Button>
+      </div>
+    </div>
+  );
+}

frontend/src/components/FileDropZone.jsx

@@ -0,0 +1,431 @@
+import React, { useCallback, useEffect, useRef, useState } from 'react';
+import { sessionFilesApi } from '../api/client';
+
+// ── Helpers ───────────────────────────────────────────────────────────────────
+
+function escapeRegex(str) {
+  return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+}
+
+/**
+ * Build a regex that matches an animal's identifier in a filename.
+ * Tries both animal_id_string and animal_name (OR logic).
+ *
+ * Rules:
+ *  - Match must not be preceded or followed by an alphanumeric char,
+ *    so "2852" matches "rat_2852_session" but not "28520" or "X2852Y".
+ *  - Multi-word names ("Rat A") allow any separator (space, dash, underscore)
+ *    between words, so "Rat A" matches "rat_a_session" and "Rat-A-data".
+ */
+function buildAnimalRegex(animal) {
+  const patterns = [];
+
+  if (animal.animal_id_string) {
+    patterns.push(escapeRegex(animal.animal_id_string));
+  }
+
+  if (animal.animal_name) {
+    const words = animal.animal_name.trim().split(/\s+/).map(escapeRegex);
+    // Single-word name: use as-is. Multi-word: allow space/dash/underscore between words.
+    patterns.push(words.length === 1 ? words[0] : words.join('[\\s_\\-]+'));
+  }
+
+  if (patterns.length === 0) return null;
+  return new RegExp(`(?<![a-zA-Z0-9])(${patterns.join('|')})(?![a-zA-Z0-9])`, 'i');
+}
+
+function classifyFile(filename) {
+  const ext = filename.split('.').pop().toLowerCase();
+  const MAP = { csv: 'CSV', tsv: 'TSV', h5: 'HDF5', hdf5: 'HDF5', nwb: 'NWB', bin: 'Binary', dat: 'Binary', raw: 'Binary', npy: 'NumPy', npz: 'NumPy', mat: 'MATLAB', pkl: 'Pickle' };
+  return MAP[ext] ?? 'Binary';
+}
+
+function fmtBytes(n) {
+  const num = typeof n === 'bigint' ? Number(n) : Number(n);
+  if (num >= 1e9)  return `${(num / 1e9).toFixed(1)} GB`;
+  if (num >= 1e6)  return `${(num / 1e6).toFixed(1)} MB`;
+  if (num >= 1e3)  return `${(num / 1e3).toFixed(1)} KB`;
+  return `${num} B`;
+}
+
+/**
+ * Match an array of File objects against animals.
+ * Returns {
+ *   matched:   Map<animalId, Array<{ file, matchedIdentifier }>>
+ *   unmatched: File[]
+ * }
+ * matchedIdentifier is the animal_id_string or animal_name value that triggered the match.
+ */
+function matchFilesToAnimals(files, animals) {
+  // Build patterns; each entry carries both alternatives so we know which one matched.
+  const entries = animals
+    .map((animal) => {
+      const alts = [];
+      if (animal.animal_id_string) alts.push({ value: animal.animal_id_string, re: new RegExp(`(?<![a-zA-Z0-9])${escapeRegex(animal.animal_id_string)}(?![a-zA-Z0-9])`, 'i') });
+      if (animal.animal_name) {
+        const words = animal.animal_name.trim().split(/\s+/).map(escapeRegex);
+        const pat   = words.length === 1 ? words[0] : words.join('[\\s_\\-]+');
+        alts.push({ value: animal.animal_name, re: new RegExp(`(?<![a-zA-Z0-9])${pat}(?![a-zA-Z0-9])`, 'i') });
+      }
+      return { animal, alts };
+    })
+    .filter((e) => e.alts.length > 0);
+
+  const matched  = new Map(animals.map((a) => [a.id, []]));
+  const unmatched = [];
+
+  for (const file of files) {
+    let found = false;
+    for (const { animal, alts } of entries) {
+      for (const { value, re } of alts) {
+        if (re.test(file.name)) {
+          matched.get(animal.id).push({ file, matchedIdentifier: value });
+          found = true;
+          break;
+        }
+      }
+      if (found) break;
+    }
+    if (!found) unmatched.push(file);
+  }
+  return { matched, unmatched };
+}
+
+// ── Sub-components ────────────────────────────────────────────────────────────
+
+function FileRow({ file, matchedIdentifier, onRemove }) {
+  return (
+    <div className="flex items-center justify-between py-1 gap-2 text-xs">
+      <span className="font-mono text-gray-700 truncate min-w-0 flex-1">{file.name}</span>
+      {matchedIdentifier && (
+        <span className="text-blue-400 shrink-0 font-mono" title="matched by">↳ {matchedIdentifier}</span>
+      )}
+      <span className="text-gray-400 shrink-0">{fmtBytes(file.size)}</span>
+      <span className="text-gray-400 shrink-0 w-12 text-right">{classifyFile(file.name)}</span>
+      {onRemove && (
+        <button type="button" onClick={onRemove}
+          className="text-red-300 hover:text-red-500 transition-colors shrink-0 ml-1">✕</button>
+      )}
+    </div>
+  );
+}
+
+function SavedFileRow({ file, onDelete, deleting }) {
+  const size = typeof file.file_size === 'string' ? BigInt(file.file_size) : file.file_size;
+  return (
+    <div className="flex items-center justify-between py-1 gap-2 text-xs">
+      <span className="font-mono text-gray-600 truncate min-w-0 flex-1">{file.filename}</span>
+      <span className="text-gray-400 shrink-0">{fmtBytes(size)}</span>
+      <span className="text-gray-400 shrink-0 w-12 text-right">{file.file_type ?? '?'}</span>
+      <button type="button" onClick={onDelete} disabled={deleting}
+        className="text-red-300 hover:text-red-500 transition-colors shrink-0 ml-1 disabled:opacity-40">✕</button>
+    </div>
+  );
+}
+
+// ── Main component ────────────────────────────────────────────────────────────
+
+/**
+ * FileDropZone
+ *
+ * Props:
+ *   rows      — array of { animal, status } from ExperimentDayView
+ *               (only rows with a status are shown; status.id is required to save files)
+ *   date      — YYYY-MM-DD string, shown in naming hint
+ */
+export default function FileDropZone({ rows, date }) {
+  const [isDragging, setIsDragging] = useState(false);
+  const [dropped, setDropped]       = useState(null);   // { matched: Map, unmatched: File[] } | null
+  const [saving, setSaving]         = useState(false);
+  const [saveError, setSaveError]   = useState(null);
+  const [savedByStatus, setSavedByStatus] = useState({}); // statusId → SavedFile[]
+  const [loadingIds, setLoadingIds]       = useState(new Set());
+  const [deletingId, setDeletingId]       = useState(null);
+  const dragCounter = useRef(0);
+
+  const statusRows = rows.filter((r) => r.status);
+  const animals    = statusRows.map((r) => r.animal);
+
+  // Load existing saved files for all statuses in this day view
+  useEffect(() => {
+    if (statusRows.length === 0) return;
+    const ids = statusRows.map((r) => r.status.id);
+    setLoadingIds(new Set(ids));
+    Promise.all(
+      ids.map((sid) => sessionFilesApi.list(sid).then((files) => ({ sid, files })))
+    ).then((results) => {
+      const map = {};
+      results.forEach(({ sid, files }) => { map[sid] = files; });
+      setSavedByStatus(map);
+      setLoadingIds(new Set());
+    }).catch(() => setLoadingIds(new Set()));
+  }, [statusRows.map((r) => r.status?.id).join(',')]); // eslint-disable-line react-hooks/exhaustive-deps
+
+  // ── Drag handlers ──────────────────────────────────────────────────────────
+
+  const onDragEnter = useCallback((e) => {
+    e.preventDefault();
+    dragCounter.current += 1;
+    if (dragCounter.current === 1) setIsDragging(true);
+  }, []);
+
+  const onDragLeave = useCallback((e) => {
+    e.preventDefault();
+    dragCounter.current -= 1;
+    if (dragCounter.current === 0) setIsDragging(false);
+  }, []);
+
+  const onDragOver = useCallback((e) => { e.preventDefault(); }, []);
+
+  const onDrop = useCallback((e) => {
+    e.preventDefault();
+    dragCounter.current = 0;
+    setIsDragging(false);
+    const files = Array.from(e.dataTransfer.files);
+    if (files.length === 0) return;
+    setDropped(matchFilesToAnimals(files, animals));
+    setSaveError(null);
+  }, [animals]);
+
+  function removeMatchedFile(animalId, fileIdx) {
+    setDropped((prev) => {
+      const next = new Map(prev.matched);
+      const arr = [...next.get(animalId)];
+      arr.splice(fileIdx, 1);
+      next.set(animalId, arr);
+      return { matched: next, unmatched: prev.unmatched };
+    });
+  }
+
+  function removeUnmatched(idx) {
+    setDropped((prev) => {
+      const u = [...prev.unmatched];
+      u.splice(idx, 1);
+      return { matched: prev.matched, unmatched: u };
+    });
+  }
+
+  // ── Save ───────────────────────────────────────────────────────────────────
+
+  async function save() {
+    if (!dropped) return;
+    setSaving(true);
+    setSaveError(null);
+    try {
+      const results = await Promise.all(
+        statusRows.map(async ({ animal, status }) => {
+          const entries = dropped.matched.get(animal.id) ?? [];
+          if (entries.length === 0) return { statusId: status.id, saved: [] };
+          const payload = entries.map(({ file, matchedIdentifier }) => ({
+            filename:              file.name,
+            file_size:             file.size,
+            file_type:             classifyFile(file.name),
+            last_modified:         file.lastModified ?? null,
+            matched_identifier:    matchedIdentifier,
+            animal_id_string_snap: animal.animal_id_string ?? null,
+            animal_name_snap:      animal.animal_name      ?? null,
+          }));
+          const saved = await sessionFilesApi.create(status.id, payload);
+          return { statusId: status.id, saved };
+        })
+      );
+      setSavedByStatus((prev) => {
+        const next = { ...prev };
+        results.forEach(({ statusId, saved }) => {
+          next[statusId] = [...(next[statusId] ?? []), ...saved];
+        });
+        return next;
+      });
+      setDropped(null);
+    } catch (err) {
+      setSaveError(err.message ?? 'Failed to save file metadata');
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  // ── Delete ─────────────────────────────────────────────────────────────────
+
+  async function deleteFile(fileId, statusId) {
+    setDeletingId(fileId);
+    try {
+      await sessionFilesApi.delete(fileId);
+      setSavedByStatus((prev) => ({
+        ...prev,
+        [statusId]: prev[statusId].filter((f) => f.id !== fileId),
+      }));
+    } catch {
+      // silently ignore — UI stays consistent, user can retry
+    } finally {
+      setDeletingId(null);
+    }
+  }
+
+  // ── Derived counts ─────────────────────────────────────────────────────────
+
+  const totalDropped       = dropped ? [...dropped.matched.values()].reduce((n, a) => n + a.length, 0) : 0;  // entries are { file, matchedIdentifier }
+  const totalUnmatched     = dropped?.unmatched.length ?? 0;
+  const totalSaved         = Object.values(savedByStatus).reduce((n, a) => n + a.length, 0);
+  const hasSaved           = totalSaved > 0;
+  const hasMatchedDropped  = totalDropped > 0;
+
+  // Hint string for naming convention
+  const sampleId = animals[0]?.animal_id_string || animals[0]?.animal_name || '<id>';
+  const namingHint = `${date}_${sampleId}_session1.csv`;
+
+  return (
+    <div className="mt-8">
+      <h3 className="text-sm font-semibold text-gray-700 mb-3">Session File Registry</h3>
+      <p className="text-xs text-gray-400 mb-4">
+        Drop all session files here. Filenames are matched to subjects by ID —
+        only metadata (name, size) is recorded; files are never uploaded.
+        <br />
+        Naming convention: <span className="font-mono text-gray-500">{namingHint}</span>
+      </p>
+
+      {/* Drop zone */}
+      <div
+        onDragEnter={onDragEnter}
+        onDragLeave={onDragLeave}
+        onDragOver={onDragOver}
+        onDrop={onDrop}
+        data-testid="drop-zone"
+        className={[
+          'border-2 border-dashed rounded-xl px-6 py-10 text-center transition-all cursor-default select-none',
+          isDragging
+            ? 'border-blue-400 bg-blue-50'
+            : 'border-gray-200 bg-gray-50 hover:border-gray-300',
+        ].join(' ')}
+      >
+        {isDragging ? (
+          <p className="text-blue-600 font-medium text-sm">Release to register files</p>
+        ) : (
+          <>
+            <p className="text-gray-400 text-sm">Drag &amp; drop session files here</p>
+            <p className="text-gray-300 text-xs mt-1">All subjects at once · files are not uploaded</p>
+          </>
+        )}
+      </div>
+
+      {/* Dropped files preview */}
+      {dropped && (
+        <div className="mt-4 space-y-4" data-testid="drop-preview">
+
+          {/* Per-subject matched files */}
+          {statusRows.map(({ animal, status }) => {
+            const entries = dropped.matched.get(animal.id) ?? [];
+            if (entries.length === 0) return null;
+            return (
+              <div key={animal.id} className="bg-white border border-gray-200 rounded-xl p-4">
+                <div className="flex items-center justify-between mb-2">
+                  <span className="text-sm font-semibold text-gray-800">
+                    {animal.animal_name}
+                    {animal.animal_id_string && (
+                      <span className="ml-1.5 text-xs font-normal text-gray-400">{animal.animal_id_string}</span>
+                    )}
+                  </span>
+                  <span className="text-xs text-gray-400">{entries.length} file{entries.length !== 1 ? 's' : ''}</span>
+                </div>
+                <div className="divide-y divide-gray-50">
+                  {entries.map(({ file, matchedIdentifier }, i) => (
+                    <FileRow key={file.name + i} file={file} matchedIdentifier={matchedIdentifier} onRemove={() => removeMatchedFile(animal.id, i)} />
+                  ))}
+                </div>
+              </div>
+            );
+          })}
+
+          {/* Subjects with no matched files */}
+          {statusRows.some(({ animal }) => (dropped.matched.get(animal.id) ?? []).length === 0) && (
+            <div className="bg-amber-50 border border-amber-100 rounded-xl p-4">
+              <p className="text-xs font-semibold text-amber-700 mb-1">No files matched for:</p>
+              {statusRows
+                .filter(({ animal }) => (dropped.matched.get(animal.id) ?? []).length === 0)
+                .map(({ animal }) => (
+                  <span key={animal.id} className="inline-block text-xs text-amber-600 bg-amber-100 rounded px-2 py-0.5 mr-1 mb-1 font-mono">
+                    {animal.animal_id_string || animal.animal_name}
+                  </span>
+                ))}
+            </div>
+          )}
+
+          {/* Unmatched files */}
+          {dropped.unmatched.length > 0 && (
+            <div className="bg-gray-50 border border-dashed border-gray-200 rounded-xl p-4">
+              <p className="text-xs font-semibold text-gray-500 mb-2">
+                Unmatched ({dropped.unmatched.length}) — no subject ID found in filename
+              </p>
+              <div className="divide-y divide-gray-100">
+                {dropped.unmatched.map((f, i) => (
+                  <FileRow key={f.name + i} file={f} onRemove={() => removeUnmatched(i)} />
+                ))}
+              </div>
+            </div>
+          )}
+
+          {saveError && (
+            <p className="text-xs text-red-500 px-1">{saveError}</p>
+          )}
+
+          {/* Action row */}
+          <div className="flex items-center gap-3 pt-1">
+            {hasMatchedDropped && (
+              <button
+                type="button"
+                onClick={save}
+                disabled={saving}
+                data-testid="save-btn"
+                className="px-4 py-2 rounded-lg text-sm font-medium bg-blue-600 text-white hover:bg-blue-700 disabled:opacity-50 transition-colors"
+              >
+                {saving ? 'Saving…' : `Register ${totalDropped} file${totalDropped !== 1 ? 's' : ''}`}
+              </button>
+            )}
+            <button
+              type="button"
+              onClick={() => { setDropped(null); setSaveError(null); }}
+              className="text-sm text-gray-400 hover:text-gray-600"
+            >
+              Clear
+            </button>
+          </div>
+        </div>
+      )}
+
+      {/* Saved files */}
+      {hasSaved && (
+        <div className="mt-6 space-y-3" data-testid="saved-files">
+          <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide">
+            Registered files ({totalSaved})
+          </p>
+          {statusRows.map(({ animal, status }) => {
+            const files = savedByStatus[status.id] ?? [];
+            if (files.length === 0) return null;
+            return (
+              <div key={animal.id} className="bg-white border border-gray-200 rounded-xl p-4">
+                <div className="flex items-center justify-between mb-2">
+                  <span className="text-sm font-semibold text-gray-800">
+                    {animal.animal_name}
+                    {animal.animal_id_string && (
+                      <span className="ml-1.5 text-xs font-normal text-gray-400">{animal.animal_id_string}</span>
+                    )}
+                  </span>
+                  <span className="text-xs text-gray-400">{files.length} file{files.length !== 1 ? 's' : ''}</span>
+                </div>
+                <div className="divide-y divide-gray-50">
+                  {files.map((f) => (
+                    <SavedFileRow
+                      key={f.id}
+                      file={f}
+                      onDelete={() => deleteFile(f.id, status.id)}
+                      deleting={deletingId === f.id}
+                    />
+                  ))}
+                </div>
+              </div>
+            );
+          })}
+        </div>
+      )}
+    </div>
+  );
+}

frontend/src/components/RunSequenceView.jsx

@@ -0,0 +1,343 @@
+import React, { useState, useEffect, useMemo } from 'react';
+
+// ── Colors ─────────────────────────────────────────────────────────────────────
+
+const BASE_COLORS = {
+  Success: { bg: 'bg-green-100', border: 'border-green-300', text: 'text-green-800', dot: 'bg-green-500', badge: 'bg-green-500' },
+  Failure: { bg: 'bg-red-100',   border: 'border-red-300',   text: 'text-red-800',   dot: 'bg-red-500',   badge: 'bg-red-500'   },
+  Other:   { bg: 'bg-gray-100',  border: 'border-gray-300',  text: 'text-gray-700',  dot: 'bg-gray-400',  badge: 'bg-gray-400'  },
+};
+const EXTRA_COLORS = [
+  { bg: 'bg-indigo-100', border: 'border-indigo-300', text: 'text-indigo-800', dot: 'bg-indigo-500', badge: 'bg-indigo-500' },
+  { bg: 'bg-yellow-100', border: 'border-yellow-300', text: 'text-yellow-800', dot: 'bg-yellow-500', badge: 'bg-yellow-500' },
+  { bg: 'bg-purple-100', border: 'border-purple-300', text: 'text-purple-800', dot: 'bg-purple-500', badge: 'bg-purple-500' },
+  { bg: 'bg-pink-100',   border: 'border-pink-300',   text: 'text-pink-800',   dot: 'bg-pink-500',   badge: 'bg-pink-500'   },
+];
+function getColors(cat, customCats = []) {
+  if (BASE_COLORS[cat]) return BASE_COLORS[cat];
+  return EXTRA_COLORS[Math.max(0, customCats.indexOf(cat)) % EXTRA_COLORS.length];
+}
+
+const ORDINALS = ['1st', '2nd', '3rd', '4th', '5th'];
+
+// ── Helpers ────────────────────────────────────────────────────────────────────
+
+/** Build display items from a sequence slice, respecting mode + collapsibility. */
+function buildItems(seqSlice, mode, collapsible) {
+  const categorised = seqSlice.filter(s => s.category);
+  if (mode === 'discrete') {
+    return categorised.map((s, i) => ({ id: i, category: s.category, count: 1 }));
+  }
+  // Rebuild runs within this slice, then apply collapsibility
+  const runs = [];
+  for (const s of categorised) {
+    if (runs.length === 0 || runs[runs.length - 1].category !== s.category) {
+      runs.push({ category: s.category, length: 1 });
+    } else {
+      runs[runs.length - 1].length++;
+    }
+  }
+  const items = [];
+  for (const run of runs) {
+    if (collapsible[run.category] === false) {
+      for (let i = 0; i < run.length; i++) items.push({ id: items.length, category: run.category, count: 1 });
+    } else {
+      items.push({ id: items.length, category: run.category, count: run.length });
+    }
+  }
+  return items;
+}
+
+/** Compute per-category counts and total for a sequence slice. */
+function segStats(seqSlice) {
+  const byCat = {};
+  for (const s of seqSlice) {
+    if (!s.category) continue;
+    byCat[s.category] = (byCat[s.category] || 0) + 1;
+  }
+  const total = Object.values(byCat).reduce((a, b) => a + b, 0);
+  return { byCat, total };
+}
+
+// ── Component ──────────────────────────────────────────────────────────────────
+
+/**
+ * Props:
+ *   runs            {category, length}[]   — global run-length-encoded sequence
+ *   sequence        {note, category, timestamp}[]
+ *   customCategories string[]
+ */
+export default function RunSequenceView({ runs = [], sequence = [], customCategories = [], sessionEndTs = null }) {
+  const [mode, setMode] = useState('grouped');
+  const [collapsible, setCollapsible] = useState({});
+  const [splitN, setSplitN] = useState(1);
+  const [durationMins, setDurationMins] = useState(20);
+  const [selectedSegment, setSelectedSegment] = useState(null);
+
+  // Initialise collapsibility for any new categories
+  const allCats = useMemo(() => [...new Set(runs.map(r => r.category))], [runs]);
+  useEffect(() => {
+    setCollapsible(prev => {
+      const next = { ...prev };
+      for (const cat of allCats) {
+        if (!(cat in next)) next[cat] = cat !== 'Success';
+      }
+      return next;
+    });
+  }, [allCats]);
+
+  // Reset selected segment when split changes
+  useEffect(() => { setSelectedSegment(null); }, [splitN]);
+
+  // ── Timestamp bounds ─────────────────────────────────────────────────────────
+
+  const { startTs, segSize, windowUnderrun } = useMemo(() => {
+    let endT = sessionEndTs != null ? sessionEndTs : null;
+    if (endT === null) {
+      const ts = sequence.map(s => parseFloat(s.timestamp)).filter(t => !isNaN(t));
+      endT = ts.length ? Math.max(...ts) : durationMins * 60;
+    }
+    const rawStart = endT - durationMins * 60;
+    return {
+      startTs: rawStart,
+      segSize: (durationMins * 60) / Math.max(splitN, 1),
+      windowUnderrun: rawStart < 0 ? Math.abs(rawStart) : 0,
+    };
+  }, [sequence, sessionEndTs, durationMins, splitN]);
+
+  function segIndexOf(timestamp) {
+    const t = parseFloat(timestamp);
+    if (isNaN(t)) return 0;
+    return Math.min(Math.max(Math.floor((t - startTs) / segSize), 0), splitN - 1);
+  }
+
+  // ── Segment data (only when split > 1) ───────────────────────────────────────
+
+  const segmentData = useMemo(() => {
+    if (splitN === 1) return null;
+    const groups = Array.from({ length: splitN }, () => []);
+    for (const s of sequence) {
+      groups[segIndexOf(s.timestamp)].push(s);
+    }
+    return groups.map((grp, i) => ({
+      index: i,
+      items: buildItems(grp, mode, collapsible),
+      stats: segStats(grp),
+    }));
+  }, [splitN, sequence, mode, collapsible, startTs, segSize]);
+
+  // ── Single-segment display items (split = 1) ─────────────────────────────────
+
+  const singleItems = useMemo(() => {
+    if (splitN !== 1) return [];
+    if (mode === 'discrete') {
+      const src = sequence.length > 0
+        ? sequence.filter(s => s.category)
+        : runs.flatMap(r => Array.from({ length: r.length }, () => ({ category: r.category })));
+      return src.map((s, i) => ({ id: i, category: s.category, count: 1 }));
+    }
+    const items = [];
+    for (const run of runs) {
+      if (collapsible[run.category] === false) {
+        for (let i = 0; i < run.length; i++) items.push({ id: items.length, category: run.category, count: 1 });
+      } else {
+        items.push({ id: items.length, category: run.category, count: run.length });
+      }
+    }
+    return items;
+  }, [splitN, mode, runs, sequence, collapsible]);
+
+  // ── Global totals ─────────────────────────────────────────────────────────────
+
+  const globalStats = useMemo(() => segStats(sequence), [sequence]);
+
+  if (runs.length === 0) return null;
+
+  const hasTimestamps = sequence.some(s => !isNaN(parseFloat(s.timestamp)));
+  const activeSegStats = selectedSegment !== null && segmentData ? segmentData[selectedSegment]?.stats ?? null : null;
+
+  // ── Render ────────────────────────────────────────────────────────────────────
+
+  return (
+    <div>
+      {/* ── Controls row ── */}
+      <div className="flex items-center flex-wrap gap-x-4 gap-y-1.5 mb-2">
+        {/* Title */}
+        <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide">
+          Run sequence ({runs.length} runs)
+        </p>
+
+        {/* Mode toggle */}
+        <div className="flex rounded border border-gray-200 overflow-hidden text-xs">
+          <button type="button" onClick={() => setMode('discrete')}
+            className={`px-2 py-0.5 transition-colors ${mode === 'discrete' ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+            Discrete
+          </button>
+          <button type="button" onClick={() => setMode('grouped')}
+            className={`px-2 py-0.5 border-l border-gray-200 transition-colors ${mode === 'grouped' ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+            Grouped
+          </button>
+        </div>
+
+        {/* Time split */}
+        {hasTimestamps && (
+          <div className="flex items-center gap-1.5 text-xs">
+            <span className="text-gray-400">Split:</span>
+            <select value={splitN} onChange={e => setSplitN(Number(e.target.value))}
+              className="border border-gray-200 rounded px-1.5 py-0.5 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400">
+              <option value={1}>None</option>
+              <option value={2}>½</option>
+              <option value={3}>⅓</option>
+              <option value={4}>¼</option>
+              <option value={5}>⅕</option>
+            </select>
+            <input
+              type="number" min={1} max={600} value={durationMins}
+              onChange={e => setDurationMins(Math.max(1, Number(e.target.value)))}
+              className="border border-gray-200 rounded px-1.5 py-0.5 w-14 text-xs text-right focus:outline-none focus:ring-1 focus:ring-indigo-400"
+              title="Experiment duration in minutes"
+            />
+            <span className="text-gray-400">min</span>
+          </div>
+        )}
+      </div>
+
+      {/* ── Per-category collapse toggles (grouped mode) ── */}
+      {mode === 'grouped' && allCats.length > 0 && (
+        <div className="flex flex-wrap gap-1.5 mb-2">
+          {allCats.map(cat => {
+            const c = getColors(cat, customCategories);
+            const isGrouped = collapsible[cat] !== false;
+            return (
+              <button key={cat} type="button"
+                onClick={() => setCollapsible(prev => ({ ...prev, [cat]: !prev[cat] }))}
+                title={isGrouped ? 'Grouped — click for discrete' : 'Discrete — click to group'}
+                className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs border transition-colors
+                  ${isGrouped ? `${c.bg} ${c.border} ${c.text}` : `bg-white ${c.border} ${c.text} opacity-70`}`}>
+                <span className={`w-1.5 h-1.5 rounded-full ${c.dot}`} />
+                {cat}: {isGrouped ? 'grouped' : 'discrete'}
+              </button>
+            );
+          })}
+        </div>
+      )}
+
+      {/* ── Underrun warning ── */}
+      {splitN > 1 && windowUnderrun > 0 && (() => {
+        const u = Math.round(windowUnderrun);
+        const m = Math.floor(u / 60), s = u % 60;
+        return (
+          <p className="text-[10px] text-amber-600 bg-amber-50 border border-amber-200 rounded px-2 py-1 mb-2">
+            The {durationMins}-min window starts {m}:{String(s).padStart(2,'0')} before the recording — the 1st segment includes unrecorded time.
+          </p>
+        );
+      })()}
+
+      {/* ── Segment buttons (when split > 1) ── */}
+      {splitN > 1 && segmentData && (
+        <div className="flex flex-wrap gap-1.5 mb-2">
+          {segmentData.map((seg, si) => {
+            const isActive = selectedSegment === si;
+            const segStart = startTs + si * segSize;
+            const segEnd   = startTs + (si + 1) * segSize;
+            const fmt = s => {
+              const t = Math.round(s);
+              const clamped = Math.max(0, t);
+              const m = Math.floor(clamped / 60);
+              const sec = clamped % 60;
+              const prefix = t < 0 ? '0:00*' : `${m}:${String(sec).padStart(2, '0')}`;
+              return prefix;
+            };
+            return (
+              <button key={si} type="button"
+                onClick={() => setSelectedSegment(prev => prev === si ? null : si)}
+                title={`${fmt(segStart)} – ${fmt(segEnd)}`}
+                className={`inline-flex flex-col items-center px-2.5 py-1 rounded-lg text-xs font-medium border transition-all
+                  ${isActive ? 'bg-gray-800 text-white border-gray-800' : 'bg-white text-gray-600 border-gray-300 hover:border-gray-400'}`}>
+                <span className="flex items-center gap-1.5">
+                  {ORDINALS[si]}
+                  <span className={`text-[10px] px-1 py-px rounded-full font-semibold
+                    ${isActive ? 'bg-white/20 text-white' : 'bg-gray-100 text-gray-500'}`}>
+                    {seg.stats.total}
+                  </span>
+                </span>
+                <span className={`text-[9px] font-normal tabular-nums ${isActive ? 'text-gray-300' : 'text-gray-400'}`}>
+                  {fmt(segStart)}–{fmt(segEnd)}
+                </span>
+              </button>
+            );
+          })}
+          {selectedSegment !== null && (
+            <button type="button" onClick={() => setSelectedSegment(null)}
+              className="text-xs text-gray-400 hover:text-gray-600 px-1">✕</button>
+          )}
+        </div>
+      )}
+
+      {/* ── Selected segment stats ── */}
+      {activeSegStats && (
+        <div className="flex flex-wrap items-center gap-3 mb-2 px-3 py-2 bg-gray-50 rounded-lg border border-gray-200 text-xs">
+          <span className="font-semibold text-gray-700">{ORDINALS[selectedSegment]} segment</span>
+          <span className="text-gray-500">{activeSegStats.total} attempt{activeSegStats.total !== 1 ? 's' : ''}</span>
+          {Object.entries(activeSegStats.byCat).sort(([, a], [, b]) => b - a).map(([cat, n]) => {
+            const c = getColors(cat, customCategories);
+            return (
+              <span key={cat} className={`inline-flex items-center gap-1 px-1.5 py-0.5 rounded-full ${c.bg} ${c.text}`}>
+                <span className={`w-1.5 h-1.5 rounded-full ${c.dot}`} />
+                {cat}: {n}
+              </span>
+            );
+          })}
+        </div>
+      )}
+
+      {/* ── Chip area ── */}
+      <div className="flex flex-wrap gap-1 items-center">
+        {splitN === 1
+          ? singleItems.map(item => <Chip key={item.id} item={item} customCategories={customCategories} dimmed={false} />)
+          : segmentData && segmentData.map((seg, si) => (
+              <React.Fragment key={si}>
+                {si > 0 && (
+                  <div className="flex flex-col items-center mx-0.5 self-stretch" aria-hidden>
+                    <div className="w-px flex-1 bg-gray-300" style={{ minHeight: 20 }} />
+                  </div>
+                )}
+                {seg.items.length === 0
+                  ? <span className="text-[10px] text-gray-300 italic px-1">empty</span>
+                  : seg.items.map(item => (
+                      <Chip key={`${si}-${item.id}`} item={item} customCategories={customCategories}
+                        dimmed={selectedSegment !== null && selectedSegment !== si} />
+                    ))}
+              </React.Fragment>
+            ))
+        }
+      </div>
+
+      {/* ── Global totals ── */}
+      <div className="flex flex-wrap items-center gap-3 mt-2 pt-2 border-t border-gray-100 text-xs text-gray-500">
+        <span className="font-medium text-gray-700">Total: {globalStats.total} attempt{globalStats.total !== 1 ? 's' : ''}</span>
+        {Object.entries(globalStats.byCat).sort(([, a], [, b]) => b - a).map(([cat, n]) => {
+          const c = getColors(cat, customCategories);
+          return (
+            <span key={cat} className={`inline-flex items-center gap-1 px-1.5 py-0.5 rounded-full ${c.bg} ${c.text}`}>
+              <span className={`w-1.5 h-1.5 rounded-full ${c.dot}`} />
+              {cat}: {n}
+            </span>
+          );
+        })}
+      </div>
+    </div>
+  );
+}
+
+function Chip({ item, customCategories, dimmed }) {
+  const c = getColors(item.category, customCategories);
+  return (
+    <span
+      title={item.count > 1 ? `${item.category} × ${item.count}` : item.category}
+      className={`inline-flex items-center px-1.5 py-0.5 rounded text-xs font-mono border transition-opacity
+        ${c.bg} ${c.text} ${c.border} ${dimmed ? 'opacity-25' : 'opacity-100'}`}>
+      {item.count > 1 ? `${item.count}×` : ''}{item.category.slice(0, 3)}
+    </span>
+  );
+}

frontend/src/components/SubjectInfoForm.jsx

@@ -0,0 +1,146 @@
+import React, { useState, useEffect } from 'react';
+import Button from './ui/Button';
+import { Input, Textarea } from './ui/FormField';
+
+function widthToSpan(pct) {
+  if (pct <= 8)  return 1;
+  if (pct <= 17) return 2;
+  if (pct <= 25) return 3;
+  if (pct <= 33) return 4;
+  if (pct <= 42) return 5;
+  if (pct <= 50) return 6;
+  if (pct <= 67) return 8;
+  if (pct <= 75) return 9;
+  return 12;
+}
+import Alert from './ui/Alert';
+import { animalsApi, experimentsApi } from '../api/client';
+
+export default function SubjectInfoForm({ animal, subjectTemplate = [], experimentId, onTemplateUpdate, onSaved, onCancel }) {
+  const activeFields = subjectTemplate.filter((f) => f.active);
+
+  function buildInitialValues() {
+    const vals = {};
+    for (const f of activeFields) {
+      vals[f.key] = animal?.subject_info?.[f.fieldId] ?? '';
+    }
+    return vals;
+  }
+
+  const [values, setValues] = useState(buildInitialValues);
+  const [apiError, setApiError] = useState(null);
+  const [loading, setLoading] = useState(false);
+  const [savingTagFor, setSavingTagFor] = useState(null);
+
+  useEffect(() => {
+    setValues(buildInitialValues());
+    setApiError(null);
+  }, [animal, subjectTemplate]);
+
+  const set = (key) => (e) => setValues((v) => ({ ...v, [key]: e.target.value }));
+
+  async function saveTag(field) {
+    const value = (values[field.key] ?? '').trim();
+    if (!value || !experimentId || !onTemplateUpdate) return;
+    setSavingTagFor(field.fieldId);
+    try {
+      const updatedTemplate = subjectTemplate.map((f) =>
+        f.fieldId === field.fieldId
+          ? { ...f, tags: [...(f.tags ?? []), value] }
+          : f
+      );
+      await experimentsApi.updateSubjectTemplate(experimentId, updatedTemplate);
+      onTemplateUpdate(updatedTemplate);
+    } catch (_) {
+    } finally {
+      setSavingTagFor(null);
+    }
+  }
+
+  async function handleSubmit(e) {
+    e.preventDefault();
+    setLoading(true);
+    setApiError(null);
+    try {
+      // Preserve any fields not in the current active template
+      const existing = animal?.subject_info ?? {};
+      const updates = {};
+      for (const f of activeFields) {
+        updates[f.fieldId] = values[f.key] || null;
+      }
+      const merged = { ...existing, ...updates };
+
+      const updated = await animalsApi.update(animal.id, { subject_info: merged });
+      onSaved(updated);
+    } catch (err) {
+      setApiError(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  if (activeFields.length === 0) {
+    return (
+      <div className="text-center py-6">
+        <p className="text-sm text-gray-400 italic">No subject info fields configured for this experiment.</p>
+        <p className="text-xs text-gray-400 mt-1">Use "Subject Template" on the experiment page to add fields.</p>
+        <div className="flex justify-end mt-4">
+          <Button variant="secondary" type="button" onClick={onCancel}>Close</Button>
+        </div>
+      </div>
+    );
+  }
+
+  return (
+    <form onSubmit={handleSubmit} noValidate>
+      {apiError && (
+        <Alert type="error" message={apiError.message} details={apiError.details} onDismiss={() => setApiError(null)} />
+      )}
+
+      <div className="grid grid-cols-12 gap-x-3 gap-y-2 mb-4">
+        {activeFields.map((field) => {
+          const isTextarea = field.type === 'textarea';
+          const span = isTextarea ? 12 : widthToSpan(field.width ?? 100);
+          const fieldTags = field.tags ?? [];
+          const currentValue = (values[field.key] ?? '').trim();
+          const canSaveTag = experimentId && onTemplateUpdate && currentValue && !fieldTags.includes(currentValue) && !field.tagsDisabled;
+          return (
+            <div key={field.fieldId} className={`col-span-${span} flex items-start gap-2`}>
+              <label className="text-xs font-medium text-gray-500 whitespace-nowrap w-28 shrink-0 text-right pt-1.5">{field.label}</label>
+              <div className="flex-1 min-w-0">
+                {isTextarea ? (
+                  <Textarea name={field.key} value={values[field.key] ?? ''} onChange={set(field.key)} disabled={loading} />
+                ) : (
+                  <Input name={field.key} value={values[field.key] ?? ''} onChange={set(field.key)} disabled={loading} />
+                )}
+                {(fieldTags.length > 0 || canSaveTag) && (
+                  <div className="flex flex-wrap items-center gap-1.5 mt-1">
+                    {fieldTags.map((tag) => (
+                      <button key={tag} type="button" title={`Quick-fill: ${tag}`}
+                        onClick={() => setValues((v) => ({ ...v, [field.key]: tag }))}
+                        className="inline-flex items-center px-2 py-0.5 rounded-full bg-indigo-50 border border-indigo-200 text-indigo-700 text-xs font-medium hover:bg-indigo-100 transition-colors">
+                        {tag}
+                      </button>
+                    ))}
+                    {canSaveTag && (
+                      <button type="button" onClick={() => saveTag(field)} disabled={savingTagFor === field.fieldId}
+                        title="Save current value as a quick-fill tag"
+                        className="inline-flex items-center gap-1 px-2 py-0.5 rounded-full border border-dashed border-indigo-300 text-indigo-500 text-xs hover:border-indigo-500 hover:text-indigo-700 transition-colors disabled:opacity-50">
+                        {savingTagFor === field.fieldId ? '…' : '+ Save as tag'}
+                      </button>
+                    )}
+                  </div>
+                )}
+              </div>
+            </div>
+          );
+        })}
+      </div>
+
+      <div className="flex justify-end gap-3 pt-2 border-t border-gray-100">
+        <Button variant="secondary" type="button" onClick={onCancel} disabled={loading}>Cancel</Button>
+        <Button type="submit" loading={loading}>Save</Button>
+      </div>
+    </form>
+  );
+}

frontend/src/components/SubjectSidebar.jsx

@@ -0,0 +1,59 @@
+import React from 'react';
+import { groupLines, groupVisibilityState } from '../lib/crossSubjectChart';
+
+// Presentational panel listing subjects grouped by their group, with per-subject
+// and per-group visibility checkboxes. All state lives in the parent; this component
+// only renders and calls handlers.
+export function SubjectSidebar({
+  lines, hiddenSubjects, onToggleSubject, onToggleGroup, onShowAll, onHighlight,
+}) {
+  const groups = groupLines(lines);
+  const anyHidden = lines.some((l) => hiddenSubjects.has(l.id));
+
+  return (
+    <div className="w-[210px] shrink-0 border-l border-gray-100 pl-3">
+      <div className="flex items-center justify-between mb-2">
+        <span className="text-xs font-semibold text-gray-500 uppercase tracking-wide">Subjects</span>
+        {anyHidden && (
+          <button type="button" onClick={onShowAll} aria-label="Show all subjects"
+            className="text-xs text-indigo-500 hover:text-indigo-700">Show all</button>
+        )}
+      </div>
+      <div className="space-y-3 max-h-[320px] overflow-y-auto pr-1">
+        {groups.map(({ group, subjects }) => {
+          const ids = subjects.map((s) => s.id);
+          const state = groupVisibilityState(ids, hiddenSubjects);
+          return (
+            <div key={group}>
+              <label className="flex items-center gap-1.5 text-xs font-medium text-gray-600 cursor-pointer">
+                <input type="checkbox"
+                  checked={state === 'all'}
+                  ref={(el) => { if (el) el.indeterminate = state === 'some'; }}
+                  onChange={() => onToggleGroup(ids, state === 'all')}
+                  className="accent-indigo-500" />
+                <span className="truncate">{group}</span>
+                <span className="text-gray-400">({subjects.length})</span>
+              </label>
+              <div className="mt-1 space-y-0.5 pl-1">
+                {subjects.map((s) => (
+                  <label key={s.id}
+                    onMouseEnter={() => onHighlight(s.id)}
+                    onMouseLeave={() => onHighlight(null)}
+                    className="flex items-center gap-1.5 text-xs text-gray-600 cursor-pointer hover:bg-gray-50 rounded px-1 py-0.5">
+                    <input type="checkbox"
+                      checked={!hiddenSubjects.has(s.id)}
+                      onChange={() => onToggleSubject(s.id)}
+                      className="accent-indigo-500" />
+                    <span className="inline-block w-2.5 h-2.5 rounded-full shrink-0"
+                      style={{ backgroundColor: s.color }} />
+                    <span className="truncate">{s.name}</span>
+                  </label>
+                ))}
+              </div>
+            </div>
+          );
+        })}
+      </div>
+    </div>
+  );
+}

frontend/src/components/TemplateEditor.jsx

@@ -0,0 +1,465 @@
+import React, { useState, useEffect, useRef } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+
+// ── helpers ────────────────────────────────────────────────────────────────────
+
+function toKey(label) {
+  return label.toLowerCase().trim()
+    .replace(/[^a-z0-9]+/g, '_').replace(/^_+|_+$/g, '').slice(0, 64);
+}
+
+// ── Tag chip ───────────────────────────────────────────────────────────────────
+
+function TagChip({ value, onRemove }) {
+  return (
+    <span className="inline-flex items-center gap-1 px-2 py-0.5 rounded-full bg-indigo-50 border border-indigo-200 text-indigo-700 text-xs font-medium">
+      {value}
+      <button
+        type="button"
+        aria-label={`Remove tag ${value}`}
+        onClick={onRemove}
+        className="text-indigo-400 hover:text-indigo-700 leading-none"
+      >✕</button>
+    </span>
+  );
+}
+
+// ── Inline tag editor (expanded panel below a field row) ──────────────────────
+
+function TagPanel({ field, onChange, onAddTag, onRemoveTag }) {
+  const [draft, setDraft] = useState('');
+  const [err, setErr] = useState('');
+  const disabled = !!field.tagsDisabled;
+
+  function commit() {
+    const v = draft.trim();
+    if (!v) { setErr('Tag cannot be empty'); return; }
+    if (v.length > 512) { setErr('Tag must be ≤512 characters'); return; }
+    if ((field.tags ?? []).includes(v)) { setErr('Tag already exists'); return; }
+    setErr('');
+    onAddTag(field.fieldId, v);
+    setDraft('');
+  }
+
+  return (
+    <div className="px-4 pb-3 pt-2 bg-indigo-50/40 border-t border-indigo-100 rounded-b-lg">
+      <div className="flex items-center justify-between mb-2">
+        <p className="text-xs font-semibold text-indigo-600 uppercase tracking-wide">Quick-fill tags</p>
+        <label className="flex items-center gap-1.5 text-xs text-gray-500 cursor-pointer select-none">
+          <input
+            type="checkbox"
+            checked={disabled}
+            onChange={(e) => onChange({ ...field, tagsDisabled: e.target.checked })}
+            className="w-3.5 h-3.5 accent-indigo-600"
+          />
+          Disable tagging
+        </label>
+      </div>
+
+      {!disabled && (
+        <>
+          <div className="flex flex-wrap gap-1.5 mb-2 min-h-[24px]">
+            {(field.tags ?? []).length === 0 && (
+              <span className="text-xs text-gray-400 italic">No tags yet.</span>
+            )}
+            {(field.tags ?? []).map((t) => (
+              <TagChip key={t} value={t} onRemove={() => onRemoveTag(field.fieldId, t)} />
+            ))}
+          </div>
+
+          <div className="flex gap-2 items-start">
+            <div className="flex-1">
+              <input
+                aria-label={`Add tag for ${field.label}`}
+                className={`w-full text-sm rounded border px-2 py-1 focus:outline-none focus:ring-2 focus:ring-indigo-400 ${err ? 'border-red-400' : 'border-gray-300'}`}
+                placeholder="Type a tag value…"
+                value={draft}
+                onChange={(e) => { setDraft(e.target.value); setErr(''); }}
+                onKeyDown={(e) => { if (e.key === 'Enter') { e.preventDefault(); commit(); } }}
+              />
+              {err && <p className="text-xs text-red-500 mt-0.5">{err}</p>}
+            </div>
+            <Button size="sm" type="button" onClick={commit}>+ Add</Button>
+          </div>
+        </>
+      )}
+
+      {disabled && (
+        <p className="text-xs text-gray-400 italic">Tagging is disabled for this field. Existing tags are preserved.</p>
+      )}
+    </div>
+  );
+}
+
+// ── Single field row (draggable) ───────────────────────────────────────────────
+
+function FieldRow({
+  field, index, total,
+  onChange, onToggle, onRemove, onAddTag, onRemoveTag,
+  allKeys,
+  // drag props
+  onDragStart, onDragEnter, onDragEnd,
+  isDragOver,
+}) {
+  const [labelDraft, setLabelDraft] = useState(field.label);
+  const [labelError, setLabelError] = useState('');
+  const [showTags, setShowTags] = useState(false);
+
+  useEffect(() => { setLabelDraft(field.label); }, [field.label]);
+
+  function commitLabel() {
+    const trimmed = labelDraft.trim();
+    if (!trimmed) { setLabelError('Label cannot be empty'); return; }
+    if (trimmed.length > 128) { setLabelError('Label must be ≤128 characters'); return; }
+    if (!field.builtin) {
+      const newKey = toKey(trimmed);
+      if (!newKey) { setLabelError('Label must contain at least one alphanumeric character'); return; }
+      if (allKeys.find((k) => k !== field.key && k === newKey)) {
+        setLabelError('A field with this name already exists'); return;
+      }
+    }
+    setLabelError('');
+    onChange({ ...field, label: trimmed, key: field.builtin ? field.key : toKey(trimmed) });
+  }
+
+  const tagCount = (field.tags ?? []).length;
+
+  return (
+    <div
+      className={`rounded-lg border transition-all ${isDragOver ? 'border-blue-400 shadow-md scale-[1.01]' : 'border-gray-200'} ${field.active ? 'bg-white' : 'bg-gray-50 opacity-60'}`}
+      draggable
+      onDragStart={() => onDragStart(index)}
+      onDragEnter={() => onDragEnter(index)}
+      onDragEnd={onDragEnd}
+      onDragOver={(e) => e.preventDefault()}
+    >
+      {/* Main row */}
+      <div className="flex items-center gap-3 px-3 py-2.5">
+        {/* Drag handle */}
+        <span
+          className="text-gray-300 hover:text-gray-500 cursor-grab active:cursor-grabbing select-none text-lg leading-none"
+          title="Drag to reorder"
+          aria-label="Drag handle"
+        >⠿</span>
+
+        {/* Label input */}
+        <div className="flex-1 min-w-0">
+          <input
+            aria-label={`Field label for ${field.key}`}
+            className={`w-full text-sm rounded border px-2 py-1 focus:outline-none focus:ring-2 focus:ring-blue-500 ${labelError ? 'border-red-400' : 'border-gray-300'} ${!field.active ? 'bg-gray-100' : 'bg-white'}`}
+            value={labelDraft}
+            disabled={!field.active}
+            onChange={(e) => { setLabelDraft(e.target.value); setLabelError(''); }}
+            onBlur={commitLabel}
+            onKeyDown={(e) => { if (e.key === 'Enter') { e.preventDefault(); commitLabel(); } }}
+          />
+          {labelError && <p className="text-xs text-red-500 mt-0.5">{labelError}</p>}
+          <p className="text-xs text-gray-400 mt-0.5 font-mono">
+            key: {field.key}
+            {field.fieldId && (
+              <span className="ml-2 text-gray-300" title={`Stable field ID: ${field.fieldId}`}>
+                · id: {field.fieldId.slice(0, 8)}…
+              </span>
+            )}
+          </p>
+        </div>
+
+        {/* Type selector */}
+        <select
+          aria-label={`Field type for ${field.key}`}
+          className="text-xs border border-gray-200 rounded px-2 py-1 bg-white focus:outline-none focus:ring-1 focus:ring-blue-400 disabled:bg-gray-100"
+          value={field.type}
+          disabled={!field.active}
+          onChange={(e) => onChange({ ...field, type: e.target.value })}
+        >
+          <option value="text">Short text</option>
+          <option value="textarea">Long text</option>
+        </select>
+
+        {/* Width (text fields only) */}
+        {field.type === 'text' && (
+          <select
+            aria-label={`Width for ${field.key}`}
+            title="Input width in the entry form"
+            className="text-xs border border-gray-200 rounded px-2 py-1 bg-white focus:outline-none focus:ring-1 focus:ring-blue-400 disabled:bg-gray-100"
+            value={field.width ?? 100}
+            disabled={!field.active}
+            onChange={(e) => onChange({ ...field, width: Number(e.target.value) })}
+          >
+            <option value={100}>Full</option>
+            <option value={75}>3/4</option>
+            <option value={67}>2/3</option>
+            <option value={50}>1/2</option>
+            <option value={42}>5/12</option>
+            <option value={33}>1/3</option>
+            <option value={25}>1/4</option>
+            <option value={17}>1/6</option>
+            <option value={8}>1/12</option>
+          </select>
+        )}
+
+        {/* Abbreviation */}
+        <input
+          aria-label={`Abbreviation for ${field.key}`}
+          className="text-xs border border-gray-200 rounded px-2 py-1 w-20 focus:outline-none focus:ring-1 focus:ring-blue-400 disabled:bg-gray-100"
+          placeholder="Abbr"
+          title="Column abbreviation (≤10 chars)"
+          maxLength={10}
+          value={field.abbr ?? ''}
+          disabled={!field.active}
+          onChange={(e) => onChange({ ...field, abbr: e.target.value })}
+        />
+
+        {/* Unit */}
+        <input
+          aria-label={`Unit for ${field.key}`}
+          className="text-xs border border-gray-200 rounded px-2 py-1 w-20 focus:outline-none focus:ring-1 focus:ring-blue-400 disabled:bg-gray-100"
+          placeholder="Unit"
+          title="Measurement unit (≤10 chars)"
+          maxLength={10}
+          value={field.unit ?? ''}
+          disabled={!field.active}
+          onChange={(e) => onChange({ ...field, unit: e.target.value })}
+        />
+
+        {/* Tags toggle */}
+        <button
+          type="button"
+          title={showTags ? 'Hide tags' : 'Manage quick-fill tags'}
+          aria-label={`Manage tags for ${field.label}`}
+          onClick={() => setShowTags((v) => !v)}
+          className={`relative text-sm px-2 py-1 rounded border transition-colors ${
+            showTags
+              ? 'border-indigo-400 bg-indigo-50 text-indigo-700'
+              : 'border-gray-200 text-gray-500 hover:bg-indigo-50 hover:border-indigo-300 hover:text-indigo-700'
+          }`}
+        >
+          🏷
+          {tagCount > 0 && (
+            <span className="absolute -top-1.5 -right-1.5 bg-indigo-600 text-white text-[10px] font-bold rounded-full w-4 h-4 flex items-center justify-center leading-none">
+              {tagCount > 9 ? '9+' : tagCount}
+            </span>
+          )}
+        </button>
+
+        {/* Hide / Show */}
+        <button
+          type="button"
+          title={field.active ? 'Hide field' : 'Show field'}
+          aria-label={field.active ? `Hide ${field.label}` : `Show ${field.label}`}
+          onClick={() => onToggle(field.fieldId)}
+          className={`text-sm px-2 py-1 rounded border transition-colors ${
+            field.active
+              ? 'border-gray-200 text-gray-500 hover:bg-yellow-50 hover:border-yellow-300 hover:text-yellow-700'
+              : 'border-green-200 text-green-600 hover:bg-green-50'
+          }`}
+        >
+          {field.active ? 'Hide' : 'Show'}
+        </button>
+
+        {/* Remove (custom fields only) */}
+        {!field.builtin && (
+          <button
+            type="button"
+            title="Remove field permanently"
+            aria-label={`Remove ${field.label}`}
+            onClick={() => onRemove(field.fieldId)}
+            className="text-sm px-2 py-1 rounded border border-red-200 text-red-500 hover:bg-red-50 transition-colors"
+          >✕</button>
+        )}
+      </div>
+
+      {/* Tag panel (collapsible) */}
+      {showTags && (
+        <TagPanel field={field} onChange={onChange} onAddTag={onAddTag} onRemoveTag={onRemoveTag} />
+      )}
+    </div>
+  );
+}
+
+// ── Main TemplateEditor ────────────────────────────────────────────────────────
+
+export default function TemplateEditor({ experimentId, onClose, loadFn, saveFn }) {
+  const [fields, setFields] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState(null);
+  const [success, setSuccess] = useState(false);
+
+  // Add-field form
+  const [newLabel, setNewLabel] = useState('');
+  const [newType, setNewType] = useState('text');
+  const [addError, setAddError] = useState('');
+
+  // Drag state
+  const dragIndex = useRef(null);
+  const [dragOverIndex, setDragOverIndex] = useState(null);
+
+  useEffect(() => {
+    const fn = loadFn ?? (() => experimentsApi.getTemplate(experimentId));
+    fn().then(setFields).catch((e) => setError(e.message)).finally(() => setLoading(false));
+  }, [experimentId]);
+
+  // ── field mutation helpers ─────────────────────────────────────────────────
+
+  function updateField(updated) {
+    setFields((prev) => prev.map((f) => f.fieldId === updated.fieldId ? updated : f));
+  }
+  function toggleField(fieldId) {
+    setFields((prev) => prev.map((f) => f.fieldId === fieldId ? { ...f, active: !f.active } : f));
+  }
+  function removeField(fieldId) {
+    setFields((prev) => prev.filter((f) => f.fieldId !== fieldId));
+  }
+
+  // ── tag helpers ────────────────────────────────────────────────────────────
+
+  function addTag(fieldId, value) {
+    setFields((prev) => prev.map((f) =>
+      f.fieldId === fieldId
+        ? { ...f, tags: [...(f.tags ?? []), value] }
+        : f
+    ));
+  }
+  function removeTag(fieldId, value) {
+    setFields((prev) => prev.map((f) =>
+      f.fieldId === fieldId
+        ? { ...f, tags: (f.tags ?? []).filter((t) => t !== value) }
+        : f
+    ));
+  }
+
+  // ── drag handlers ──────────────────────────────────────────────────────────
+
+  function handleDragStart(index) {
+    dragIndex.current = index;
+  }
+  function handleDragEnter(index) {
+    setDragOverIndex(index);
+  }
+  function handleDragEnd() {
+    const from = dragIndex.current;
+    const to   = dragOverIndex;
+    if (from !== null && to !== null && from !== to) {
+      setFields((prev) => {
+        const next = [...prev];
+        const [moved] = next.splice(from, 1);
+        next.splice(to, 0, moved);
+        return next;
+      });
+    }
+    dragIndex.current = null;
+    setDragOverIndex(null);
+  }
+
+  // ── add new field ──────────────────────────────────────────────────────────
+
+  function addField() {
+    const trimmed = newLabel.trim();
+    if (!trimmed) { setAddError('Field name is required'); return; }
+    const key = toKey(trimmed);
+    if (!key) { setAddError('Name must contain at least one alphanumeric character'); return; }
+    if (fields.some((f) => f.key === key)) { setAddError(`A field with key "${key}" already exists`); return; }
+    setAddError('');
+    const fieldId = crypto.randomUUID();
+    setFields((prev) => [...prev, { fieldId, key, label: trimmed, type: newType, builtin: false, active: true, tags: [] }]);
+    setNewLabel('');
+    setNewType('text');
+  }
+
+  // ── save ───────────────────────────────────────────────────────────────────
+
+  async function save() {
+    setSaving(true);
+    setError(null);
+    try {
+      const fn = saveFn ?? ((f) => experimentsApi.updateTemplate(experimentId, f));
+      await fn(fields);
+      setSuccess(true);
+      setTimeout(() => { setSuccess(false); onClose(fields); }, 700);
+    } catch (e) {
+      setError(e.message);
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  const allKeys = fields.map((f) => f.key);
+
+  return (
+    <div className="space-y-4">
+      {loading && <p className="text-sm text-gray-400">Loading template…</p>}
+      {error   && <Alert type="error"   message={error}          onDismiss={() => setError(null)} />}
+      {success && <Alert type="success" message="Template saved!" />}
+
+      {!loading && (
+        <>
+          {/* Field list */}
+          <div className="space-y-2">
+            {fields.length === 0 && (
+              <p className="text-sm text-gray-400 italic text-center py-4">No fields yet. Add one below.</p>
+            )}
+            {fields.map((field, index) => (
+              <FieldRow
+                key={field.fieldId}
+                field={field}
+                index={index}
+                total={fields.length}
+                onChange={updateField}
+                onToggle={toggleField}
+                onRemove={removeField}
+                onAddTag={addTag}
+                onRemoveTag={removeTag}
+                allKeys={allKeys}
+                onDragStart={handleDragStart}
+                onDragEnter={handleDragEnter}
+                onDragEnd={handleDragEnd}
+                isDragOver={dragOverIndex === index}
+              />
+            ))}
+          </div>
+
+          {/* Add new field */}
+          <div className="border-t pt-4">
+            <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-2">Add New Field</p>
+            <div className="flex gap-2 items-start">
+              <div className="flex-1">
+                <input
+                  aria-label="New field name"
+                  className={`w-full text-sm rounded border px-3 py-2 focus:outline-none focus:ring-2 focus:ring-blue-500 ${addError ? 'border-red-400' : 'border-gray-300'}`}
+                  placeholder="Field name, e.g. Blood Pressure"
+                  value={newLabel}
+                  onChange={(e) => { setNewLabel(e.target.value); setAddError(''); }}
+                  onKeyDown={(e) => { if (e.key === 'Enter') { e.preventDefault(); addField(); } }}
+                />
+                {addError && <p className="text-xs text-red-500 mt-0.5">{addError}</p>}
+              </div>
+              <select
+                aria-label="New field type"
+                className="text-sm border border-gray-300 rounded px-2 py-2 bg-white focus:outline-none focus:ring-1 focus:ring-blue-400"
+                value={newType}
+                onChange={(e) => setNewType(e.target.value)}
+              >
+                <option value="text">Short text</option>
+                <option value="textarea">Long text</option>
+              </select>
+              <Button size="sm" type="button" onClick={addField}>+ Add</Button>
+            </div>
+          </div>
+
+          <p className="text-xs text-gray-400">
+            Drag <span className="font-mono">⠿</span> to reorder · <strong>Hide</strong> removes a builtin field from forms while preserving its data · <strong>🏷</strong> manages quick-fill tags
+          </p>
+
+          {/* Actions */}
+          <div className="flex justify-end gap-3 border-t pt-4">
+            <Button variant="secondary" onClick={() => onClose(null)} disabled={saving}>Cancel</Button>
+            <Button onClick={save} loading={saving}>Save Template</Button>
+          </div>
+        </>
+      )}
+    </div>
+  );
+}

frontend/src/components/ui/ConfirmDialog.jsx

@@ -1,16 +1,37 @@
-import React from 'react';
+import React, { useState, useEffect } from 'react';
 import Modal from './Modal';
 import Button from './Button';
 
-export default function ConfirmDialog({ isOpen, onClose, onConfirm, title, message, loading }) {
+export default function ConfirmDialog({ isOpen, onClose, onConfirm, title, message, loading, confirmWord }) {
+  const [typed, setTyped] = useState('');
+
+  useEffect(() => { if (!isOpen) setTyped(''); }, [isOpen]);
+
+  const ready = confirmWord ? typed === confirmWord : true;
+
   return (
     <Modal isOpen={isOpen} onClose={onClose} title={title} size="sm">
-      <p className="text-sm text-gray-600 mb-6">{message}</p>
+      <p className="text-sm text-gray-600 mb-4">{message}</p>
+      {confirmWord && (
+        <div className="mb-5">
+          <label className="block text-xs text-gray-500 mb-1">
+            Type <span className="font-mono font-semibold text-gray-700">{confirmWord}</span> to confirm
+          </label>
+          <input
+            type="text"
+            value={typed}
+            onChange={(e) => setTyped(e.target.value)}
+            autoFocus
+            className="w-full border border-gray-300 rounded-lg px-3 py-1.5 text-sm focus:outline-none focus:ring-2 focus:ring-red-300 focus:border-red-400"
+            placeholder={confirmWord}
+          />
+        </div>
+      )}
       <div className="flex justify-end gap-3">
         <Button variant="secondary" onClick={onClose} disabled={loading}>
           Cancel
         </Button>
-        <Button variant="danger" onClick={onConfirm} loading={loading}>
+        <Button variant="danger" onClick={onConfirm} loading={loading} disabled={!ready}>
           Delete
         </Button>
       </div>

frontend/src/components/ui/Modal.jsx

@@ -10,7 +10,7 @@ export default function Modal({ isOpen, onClose, title, children, size = 'md' })
 
   if (!isOpen) return null;
 
-  const widths = { sm: 'max-w-md', md: 'max-w-lg', lg: 'max-w-2xl', xl: 'max-w-4xl' };
+  const widths = { sm: 'max-w-md', md: 'max-w-lg', lg: 'max-w-2xl', xl: 'max-w-4xl', full: 'w-[75vw] max-w-none' };
 
   return (
     <div

frontend/src/lib/crossSubjectChart.js

@@ -0,0 +1,111 @@
+// Pure helpers for the cross-subject metrics plot interactions. No React, no I/O.
+
+// Sort a Recharts tooltip payload by numeric value descending, dropping entries
+// whose value is null/undefined. Returns a NEW array (does not mutate input).
+export function sortPayloadByValueDesc(payload) {
+  if (!Array.isArray(payload)) return [];
+  return payload
+    .filter((p) => p && p.value != null)
+    .sort((a, b) => b.value - a.value);
+}
+
+// Toggle an id's membership in a Set, returning a NEW Set.
+export function toggleInSet(set, id) {
+  const next = new Set(set);
+  if (next.has(id)) next.delete(id);
+  else next.add(id);
+  return next;
+}
+
+// Add (hidden=true) or remove (hidden=false) a list of ids from a hidden-set.
+// Returns a NEW Set.
+export function setIdsHidden(set, ids, hidden) {
+  const next = new Set(set);
+  for (const id of ids) {
+    if (hidden) next.add(id);
+    else next.delete(id);
+  }
+  return next;
+}
+
+// Tri-state for a group checkbox given which subject ids are hidden.
+// 'all' = all visible, 'none' = all hidden, 'some' = mixed.
+export function groupVisibilityState(subjectIds, hiddenSet) {
+  if (subjectIds.length === 0) return 'none';
+  const hiddenCount = subjectIds.filter((id) => hiddenSet.has(id)).length;
+  if (hiddenCount === 0) return 'all';
+  if (hiddenCount === subjectIds.length) return 'none';
+  return 'some';
+}
+
+// Group chart "lines" by their .group field, preserving first-seen group order
+// and line order within each group. Returns [{ group, subjects: [line...] }].
+export function groupLines(lines) {
+  const order = [];
+  const byGroup = new Map();
+  for (const line of lines) {
+    const g = line.group ?? '—';
+    if (!byGroup.has(g)) { byGroup.set(g, []); order.push(g); }
+    byGroup.get(g).push(line);
+  }
+  return order.map((group) => ({ group, subjects: byGroup.get(group) }));
+}
+
+// ── Plot config (de)serialization ───────────────────────────────────────────────
+// Translate between ExperimentAnalysisCharts React state and the stored JSONB blob.
+// readPlotConfig is defensive: it never throws and fills safe defaults for missing
+// or malformed input (unknown keys are ignored).
+
+// Symmetric with readChart so a serialize→read round-trip is lossless.
+function snapshotChart(s = {}) {
+  const str = (v) => (typeof v === 'string' ? v : '');
+  return {
+    height:         Number.isFinite(s.height) ? s.height : undefined,
+    yMin:           str(s.yMin),
+    yMax:           str(s.yMax),
+    xZoomMin:       str(s.xZoomMin),
+    xZoomMax:       str(s.xZoomMax),
+    xFieldOverride: typeof s.xFieldOverride === 'string' ? s.xFieldOverride : null,
+  };
+}
+
+export function serializePlotConfig(state = {}) {
+  const { xField, groupBy, tickStep, metric, hiddenSubjects, sidebarOpen, counts, rate } = state;
+  return {
+    xField,
+    groupBy,
+    tickStep,
+    metric,
+    hiddenSubjects: [...(hiddenSubjects ?? [])].sort(),
+    sidebarOpen: !!sidebarOpen,
+    counts: snapshotChart(counts),
+    rate:   snapshotChart(rate),
+  };
+}
+
+function readChart(c) {
+  const o = c && typeof c === 'object' && !Array.isArray(c) ? c : {};
+  const str = (v) => (typeof v === 'string' ? v : '');
+  return {
+    height:         Number.isFinite(o.height) ? o.height : undefined,
+    yMin:           str(o.yMin),
+    yMax:           str(o.yMax),
+    xZoomMin:       str(o.xZoomMin),
+    xZoomMax:       str(o.xZoomMax),
+    xFieldOverride: typeof o.xFieldOverride === 'string' ? o.xFieldOverride : null,
+  };
+}
+
+export function readPlotConfig(raw) {
+  const c = raw && typeof raw === 'object' && !Array.isArray(raw) ? raw : {};
+  return {
+    xField:   typeof c.xField === 'string' ? c.xField : undefined,
+    groupBy:  typeof c.groupBy === 'string' ? c.groupBy : undefined,
+    tickStep: Number.isFinite(c.tickStep) ? c.tickStep : undefined,
+    metric:   typeof c.metric === 'string' ? c.metric : undefined,
+    hiddenSubjects: Array.isArray(c.hiddenSubjects) ? c.hiddenSubjects.filter((x) => typeof x === 'string') : [],
+    sidebarOpen: c.sidebarOpen === true,
+    counts: readChart(c.counts),
+    rate:   readChart(c.rate),
+  };
+}

frontend/src/lib/csvAnalysis.js

@@ -0,0 +1,265 @@
+/**
+ * CSV Analysis Library
+ *
+ * Method summary:
+ *
+ * 1. PARSING
+ *    - parseCSVHeaders(text): reads only the first line, splits on comma
+ *      (handles double-quoted fields with embedded commas).
+ *    - parseCSV(text): full parse into array-of-objects. Each row is
+ *      { [headerName]: value, ... }. Empty trailing fields are preserved as ''.
+ *
+ * 2. UNIQUE VALUES
+ *    - getUniqueNoteValues(rows, noteCol): scans each row's noteCol,
+ *      trims whitespace, ignores empty strings, returns sorted unique values.
+ *
+ * 3. ANALYSIS  (runAnalysis)
+ *    Input:
+ *      rows          — full parsed rows
+ *      timestampCol  — column name to sort by (numeric sort; falls back to row order)
+ *      noteCol       — column containing note values
+ *      classifications — plain object: { noteValue: categoryName }
+ *                        unclassified notes are included in the sequence
+ *                        but excluded from category counts and run stats.
+ *
+ *    Steps:
+ *      a) Filter to rows where noteCol is non-empty.
+ *      b) Sort by timestampCol (parseFloat; NaN values go to the end).
+ *      c) Map each row to { note, category, timestamp }.
+ *      d) CATEGORY COUNTS: for each category, count total occurrences
+ *         and per-note-value breakdown.
+ *      e) RUN-LENGTH ENCODING (consecutive stat):
+ *         Walk the category sequence. Each time the category changes,
+ *         start a new run. Uncategorised notes are skipped (do not break
+ *         or continue a run). This gives an ordered list of
+ *         { category, length } objects representing every streak.
+ *      f) CONSECUTIVE STATS per category:
+ *         From the runs list, group run lengths per category and compute
+ *         totalRuns, maxRun, avgRun, and the full runLengths array.
+ *
+ *    Output: { totalNoteRows, sequence, categoryCounts, runs, consecutiveStats }
+ */
+
+// ── CSV parsing ────────────────────────────────────────────────────────────────
+
+function splitCSVLine(line) {
+  const fields = [];
+  let field = '';
+  let inQuotes = false;
+  for (let i = 0; i < line.length; i++) {
+    const ch = line[i];
+    if (ch === '"') {
+      if (inQuotes && line[i + 1] === '"') { field += '"'; i++; }
+      else { inQuotes = !inQuotes; }
+    } else if (ch === ',' && !inQuotes) {
+      fields.push(field);
+      field = '';
+    } else {
+      field += ch;
+    }
+  }
+  fields.push(field);
+  return fields;
+}
+
+/** Return column names from the first line of a CSV string. */
+export function parseCSVHeaders(text) {
+  const firstLine = text.split(/\r?\n/)[0];
+  return splitCSVLine(firstLine);
+}
+
+/** Parse the full CSV into { headers, rows }. */
+export function parseCSV(text) {
+  const lines = text.split(/\r?\n/);
+  const headers = splitCSVLine(lines[0]);
+  const rows = [];
+  for (let i = 1; i < lines.length; i++) {
+    const line = lines[i];
+    if (!line.trim()) continue;
+    const values = splitCSVLine(line);
+    const row = {};
+    for (let j = 0; j < headers.length; j++) {
+      row[headers[j]] = values[j] ?? '';
+    }
+    rows.push(row);
+  }
+  return { headers, rows };
+}
+
+// ── Unique note values ─────────────────────────────────────────────────────────
+
+/** Return sorted unique non-empty values found in noteCol. */
+export function getUniqueNoteValues(rows, noteCol) {
+  const seen = new Set();
+  for (const row of rows) {
+    const v = (row[noteCol] ?? '').trim();
+    if (v) seen.add(v);
+  }
+  return [...seen].sort();
+}
+
+// ── Frame gap detection ────────────────────────────────────────────────────────
+
+/**
+ * Check whether a numeric column is strictly consecutive (no gaps, no duplicates).
+ * Returns { consecutive: bool, gaps: [{index, expected, actual, jump}], duplicates: [{index, value}] }
+ * Only examines rows where the column value parses as an integer.
+ */
+export function checkFrameConsecutive(rows, frameCol) {
+  const entries = [];
+  for (let i = 0; i < rows.length; i++) {
+    const v = rows[i][frameCol];
+    if (v == null || String(v).trim() === '') continue;
+    const n = parseInt(v, 10);
+    if (isNaN(n)) continue;
+    entries.push({ rowIndex: i, value: n });
+  }
+
+  const gaps = [];
+  const duplicates = [];
+  for (let i = 1; i < entries.length; i++) {
+    const diff = entries[i].value - entries[i - 1].value;
+    if (diff === 0) {
+      duplicates.push({ rowIndex: entries[i].rowIndex, value: entries[i].value });
+    } else if (diff !== 1) {
+      gaps.push({
+        rowIndex: entries[i].rowIndex,
+        expected: entries[i - 1].value + 1,
+        actual:   entries[i].value,
+        jump:     diff,
+      });
+    }
+  }
+
+  return { consecutive: gaps.length === 0 && duplicates.length === 0, gaps, duplicates, total: entries.length };
+}
+
+// ── Analysis ───────────────────────────────────────────────────────────────────
+
+/**
+ * Run the full analysis.
+ *
+ * @param {object[]} rows              - Parsed CSV rows
+ * @param {string}   timestampCol      - Column to sort by
+ * @param {string}   noteCol           - Column with note values
+ * @param {object}   classifications   - { noteValue: categoryName }
+ * @returns {object} Analysis result
+ */
+export function runAnalysis(rows, timestampCol, noteCol, classifications) {
+  // Compute session end from ALL rows (not just note rows)
+  let sessionEndTs = null;
+  for (const r of rows) {
+    const t = parseFloat(r[timestampCol]);
+    if (!isNaN(t) && (sessionEndTs === null || t > sessionEndTs)) sessionEndTs = t;
+  }
+
+  // a) Filter non-empty notes
+  const noteRows = rows.filter(r => (r[noteCol] ?? '').trim() !== '');
+
+  // b) Sort by timestamp (numeric); preserve original order for equal/NaN timestamps
+  noteRows.sort((a, b) => {
+    const ta = parseFloat(a[timestampCol]);
+    const tb = parseFloat(b[timestampCol]);
+    if (isNaN(ta) && isNaN(tb)) return 0;
+    if (isNaN(ta)) return 1;
+    if (isNaN(tb)) return -1;
+    return ta - tb;
+  });
+
+  // c) Build sequence
+  const sequence = noteRows.map(r => ({
+    note:      r[noteCol].trim(),
+    category:  classifications[r[noteCol].trim()] ?? null,
+    timestamp: r[timestampCol],
+  }));
+
+  // d) Category counts
+  const categoryCounts = {};
+  for (const { note, category } of sequence) {
+    if (!category) continue;
+    if (!categoryCounts[category]) categoryCounts[category] = { total: 0, byNote: {} };
+    categoryCounts[category].total++;
+    categoryCounts[category].byNote[note] = (categoryCounts[category].byNote[note] || 0) + 1;
+  }
+
+  // e) Run-length encoding (skip uncategorised entries — they neither break nor extend a run)
+  const runs = [];
+  for (const { category } of sequence) {
+    if (!category) continue;
+    if (runs.length === 0 || runs[runs.length - 1].category !== category) {
+      runs.push({ category, length: 1 });
+    } else {
+      runs[runs.length - 1].length++;
+    }
+  }
+
+  // f) Consecutive stats per category
+  const consecutiveStats = {};
+  for (const { category, length } of runs) {
+    if (!consecutiveStats[category]) {
+      consecutiveStats[category] = { runLengths: [], totalRuns: 0, maxRun: 0, avgRun: 0 };
+    }
+    const s = consecutiveStats[category];
+    s.runLengths.push(length);
+    s.totalRuns++;
+    if (length > s.maxRun) s.maxRun = length;
+  }
+  for (const cat of Object.keys(consecutiveStats)) {
+    const s = consecutiveStats[cat];
+    s.avgRun = s.runLengths.reduce((a, b) => a + b, 0) / s.runLengths.length;
+  }
+
+  return {
+    totalNoteRows: noteRows.length,
+    sessionEndTs,
+    sequence,
+    categoryCounts,
+    runs,
+    consecutiveStats,
+  };
+}
+
+// ── Numeric extraction (for numerical buckets) ────────────────────────────────
+
+/**
+ * Extract the first signed decimal from a string. Returns null if none found.
+ * Examples: "L25.5" -> 25.5, "R-12" -> -12, "abc" -> null
+ */
+export function extractNumber(str) {
+  if (str == null) return null;
+  const m = String(str).match(/-?\d+(\.\d+)?/);
+  return m ? parseFloat(m[0]) : null;
+}
+
+/**
+ * Build a numeric-vs-x series for a numerical bucket.
+ *
+ * @param {object[]} rows       - Parsed CSV rows
+ * @param {string}   xColName   - Column to plot on the x-axis (frame col, or timestamp as fallback)
+ * @param {string}   noteCol    - Column containing note values
+ * @param {object}   bucket     - { name, type:'numerical', notes: string[] }
+ * @returns {{points: {x:number,value:number,raw:string}[], avg:number|null, skipped:number, total:number, xLabel:string}}
+ */
+export function computeNumericSeries(rows, xColName, noteCol, bucket) {
+  const noteSet = new Set(bucket.notes);
+  const points = [];
+  let skipped = 0;
+  let total = 0;
+
+  for (const r of rows) {
+    const note = String(r[noteCol] ?? '').trim();
+    if (!noteSet.has(note)) continue;
+    total++;
+    const value = extractNumber(note);
+    const x = parseFloat(r[xColName]);
+    if (value == null || Number.isNaN(x)) { skipped++; continue; }
+    points.push({ x, value, raw: note });
+  }
+
+  points.sort((a, b) => a.x - b.x);
+  const avg = points.length === 0
+    ? null
+    : points.reduce((s, p) => s + p.value, 0) / points.length;
+
+  return { points, avg, skipped, total, xLabel: xColName };
+}

frontend/src/lib/dataExport.js

@@ -0,0 +1,247 @@
+// Pure helpers for exporting daily-parameter data as a CSV matrix. The export is a
+// subject-series matrix: subjects are always columns, the chosen X coordinate
+// (Date / # Days Reach / a daily field) provides the rows, and one Data
+// parameter supplies the cell values.
+// No React, no I/O — mirrors the crossSubjectChart.js pure-helper pattern.
+
+// Read a single parameter's raw value from one daily status.
+// Returns null when the value is absent. Note: 0 and '' are returned as-is
+// (real values); only genuinely-missing lookups become null.
+export function extractValue(status, param) {
+  if (!status || !param) return null;
+  switch (param.kind) {
+    case 'total':
+      return status.analysis_summary?.total ?? null;
+    case 'success_rate':
+      return status.analysis_summary?.success_rate ?? null;
+    case 'category':
+      return status.analysis_summary?.counts?.[param.category] ?? null;
+    case 'builtin':
+      return status[param.statusKey] ?? null;
+    case 'custom':
+      return status.custom_fields?.[param.fieldId] ?? null;
+    default:
+      return null;
+  }
+}
+
+// Build the grouped, ordered list of exportable parameters.
+// Session metrics (total, success_rate, then each dynamic count category found
+// in the data) come first; then every field defined in the daily template,
+// including inactive ones (historical data may exist).
+export function listExportableParams(dailyTemplate, statuses) {
+  const params = [
+    { id: '__total__', label: 'Total attempts', group: 'metrics', kind: 'total' },
+    { id: '__success_rate__', label: 'Success rate', group: 'metrics', kind: 'success_rate' },
+  ];
+
+  const cats = new Set();
+  for (const s of statuses ?? []) {
+    const counts = s?.analysis_summary?.counts;
+    if (counts && typeof counts === 'object') {
+      for (const k of Object.keys(counts)) cats.add(k);
+    }
+  }
+  for (const cat of [...cats].sort()) {
+    params.push({ id: `__cat__${cat}`, label: cat, group: 'metrics', kind: 'category', category: cat });
+  }
+
+  for (const f of dailyTemplate ?? []) {
+    if (f.builtin) {
+      params.push({ id: `b:${f.fieldId}`, label: f.label, group: 'daily', kind: 'builtin', statusKey: f.key });
+    } else {
+      params.push({ id: `c:${f.fieldId}`, label: f.label, group: 'daily', kind: 'custom', fieldId: f.fieldId });
+    }
+  }
+
+  return params;
+}
+
+// Numeric value of a daily field on one status (mirrors the metrics plot's helper).
+export function numericFieldVal(status, field) {
+  if (!field) return null;
+  const raw = field.builtin ? status?.[field.key] : status?.custom_fields?.[field.fieldId];
+  const n = parseFloat(raw);
+  return Number.isNaN(n) ? null : n;
+}
+
+// Ordered row members for the chosen X coordinate.
+// xField: '__date__' | '__days__' | <daily fieldId>
+export function listSampleMembers(statuses, xField, dailyTemplate) {
+  const list = statuses ?? [];
+  if (xField === '__date__') {
+    const keys = new Set();
+    for (const s of list) if (s?.date) keys.add(dateKey(s.date));
+    return [...keys].sort().map((k) => ({ id: k, label: k, sampleValue: k }));
+  }
+  if (xField === '__days__') {
+    const counts = new Map();
+    for (const s of list) {
+      if (s?.animal_id == null || !s?.date) continue;
+      counts.set(s.animal_id, (counts.get(s.animal_id) ?? 0) + 1);
+    }
+    const max = counts.size ? Math.max(...counts.values()) : 0;
+    return Array.from({ length: max }, (_, i) => ({ id: String(i + 1), label: String(i + 1), sampleValue: i + 1 }));
+  }
+  const field = (dailyTemplate ?? []).find((f) => f.fieldId === xField);
+  const vals = new Set();
+  for (const s of list) {
+    const v = numericFieldVal(s, field);
+    if (v !== null) vals.add(v);
+  }
+  return [...vals].sort((a, b) => a - b).map((v) => ({ id: String(v), label: String(v), sampleValue: v }));
+}
+
+// animalId -> Map(sampleValue -> status). First status per (subject, sampleValue) wins,
+// scanning each subject's statuses in ascending date order.
+export function buildSampleIndex(statuses, xField, dailyTemplate) {
+  const bySubject = new Map();
+  for (const s of statuses ?? []) {
+    if (s?.animal_id == null || !s?.date) continue;
+    if (!bySubject.has(s.animal_id)) bySubject.set(s.animal_id, []);
+    bySubject.get(s.animal_id).push(s);
+  }
+  const field = xField !== '__date__' && xField !== '__days__'
+    ? (dailyTemplate ?? []).find((f) => f.fieldId === xField)
+    : null;
+
+  const index = new Map();
+  for (const [animalId, subjStatuses] of bySubject) {
+    const ordered = [...subjStatuses].sort((a, b) => dateKey(a.date).localeCompare(dateKey(b.date)));
+    const m = new Map();
+    ordered.forEach((s, i) => {
+      let key;
+      if (xField === '__date__') key = dateKey(s.date);
+      else if (xField === '__days__') key = i + 1;
+      else { const v = numericFieldVal(s, field); if (v === null) return; key = v; }
+      if (!m.has(key)) m.set(key, s);
+    });
+    index.set(animalId, m);
+  }
+  return index;
+}
+
+function xFieldLabel(xField, dailyTemplate) {
+  if (xField === '__date__') return 'Date';
+  if (xField === '__days__') return '# Days Reach (ordinal)';
+  return (dailyTemplate ?? []).find((f) => f.fieldId === xField)?.label ?? '';
+}
+
+// Subjects as columns, X-field values as rows, one Data value per cell.
+// Returns the { context, corner, groupAxis, columns, rows } shape toCSV consumes.
+export function buildSubjectSeriesMatrix({ xField, dataParam, groupField }, { statuses, animals, dailyTemplate }) {
+  const columns = listSubjectMembers(animals, groupField);
+  const rowMembers = listSampleMembers(statuses, xField, dailyTemplate);
+  const index = buildSampleIndex(statuses, xField, dailyTemplate);
+
+  const cellValue = (sampleValue, animalId) => {
+    const status = index.get(animalId)?.get(sampleValue);
+    if (!status || !dataParam) return '';
+    const v = extractValue(status, dataParam);
+    return hasValue(v) ? v : '';
+  };
+
+  let rows = rowMembers.map((rm) => ({
+    member: rm,
+    values: columns.map((c) => cellValue(rm.sampleValue, c.animalId)),
+  }));
+  rows = rows.filter((r) => r.values.some((v) => v !== '')); // drop entirely-blank sample rows
+
+  const grouped = !!groupField && groupField !== '__none__';
+  return {
+    corner: xFieldLabel(xField, dailyTemplate),
+    context: { label: 'Data', value: dataParam?.label ?? '' },
+    groupAxis: grouped ? 'col' : null,
+    columns,
+    rows,
+  };
+}
+
+// Resolve a subject's group value for a given group field id.
+// null  -> no grouping (field is falsy or '__none__')
+// '—'   -> grouping is on but this subject has no value
+export function subjectGroupValue(animal, groupField) {
+  if (!groupField || groupField === '__none__') return null;
+  if (groupField === '__name__') return animal?.animal_name ?? '—';
+  if (groupField === '__id__') return animal?.animal_id_string ?? '—';
+  const v = animal?.subject_info?.[groupField];
+  return v === null || v === undefined || v === '' ? '—' : v;
+}
+
+export function listSubjectMembers(animals, groupField) {
+  const list = [...(animals ?? [])];
+  const nameCounts = new Map();
+  for (const a of list) {
+    const n = a?.animal_name ?? '';
+    nameCounts.set(n, (nameCounts.get(n) ?? 0) + 1);
+  }
+  const members = list.map((a) => {
+    const name = a?.animal_name ?? '';
+    const label = nameCounts.get(name) > 1 ? `${name} (${a?.animal_id_string ?? ''})` : name;
+    return { id: a?.id, label, animalId: a?.id, group: subjectGroupValue(a, groupField) };
+  });
+  const grouped = !!groupField && groupField !== '__none__';
+  members.sort((x, y) => {
+    if (grouped) {
+      const g = String(x.group ?? '').localeCompare(String(y.group ?? ''));
+      if (g !== 0) return g;
+    }
+    return String(x.label).localeCompare(String(y.label));
+  });
+  return members;
+}
+
+// A cell has a value unless it is null, undefined, or the empty string.
+// (0 and false are real values.)
+function hasValue(v) {
+  return v !== null && v !== undefined && v !== '';
+}
+
+function dateKey(date) {
+  return String(date).slice(0, 10); // ISO datetime or date → YYYY-MM-DD
+}
+
+function escapeCsvCell(value) {
+  const s = value === null || value === undefined ? '' : String(value);
+  return /[",\n]/.test(s) ? `"${s.replace(/"/g, '""')}"` : s;
+}
+
+// Serialize a matrix to an RFC-4180-ish CSV string (LF line endings):
+//   Data,<metric>
+//   (blank line)
+//   [Group,<group per subject column>]    -- only when groupAxis === 'col'
+//   <corner>[,Group?],<column headers...>
+//   <row label>[,group?],<values...>
+export function toCSV(matrix) {
+  const lines = [];
+  lines.push([matrix.context.label, matrix.context.value].map(escapeCsvCell).join(','));
+  lines.push('');
+
+  if (matrix.groupAxis === 'col') {
+    const groupRow = ['Group', ...matrix.columns.map((c) => c.group ?? '—')];
+    lines.push(groupRow.map(escapeCsvCell).join(','));
+  }
+
+  // toCSV is a general serializer; the subject-series builder never emits groupAxis
+  // === 'row' (only 'col' or null), but the branch is retained for that generality.
+  const header = matrix.groupAxis === 'row'
+    ? ['Group', matrix.corner, ...matrix.columns.map((c) => c.label)]
+    : [matrix.corner, ...matrix.columns.map((c) => c.label)];
+  lines.push(header.map(escapeCsvCell).join(','));
+
+  for (const r of matrix.rows) {
+    const lead = matrix.groupAxis === 'row'
+      ? [r.member.group ?? '—', r.member.label]
+      : [r.member.label];
+    lines.push([...lead, ...r.values].map(escapeCsvCell).join(','));
+  }
+
+  return lines.join('\n');
+}
+
+// Build a download filename from the experiment title and parameter label.
+export function csvFilename(title, label) {
+  const slug = (s) => String(s ?? '').replace(/[^a-z0-9]+/gi, '-').replace(/^-+|-+$/g, '');
+  const base = [slug(title), slug(label)].filter(Boolean).join('-');
+  return `${base || 'export'}.csv`;
+}

frontend/src/pages/AnimalDetail.jsx

@@ -1,20 +1,119 @@
-import React, { useEffect, useState } from 'react';
-import { useParams, useNavigate, Link } from 'react-router-dom';
-import { animalsApi, dailyStatusesApi } from '../api/client';
+import React, { useEffect, useRef, useState, useCallback } from 'react';
+import { useParams, useNavigate, Link, useLocation } from 'react-router-dom';
+import { animalsApi, dailyStatusesApi, experimentsApi } from '../api/client';
 import { format } from 'date-fns';
 import Button from '../components/ui/Button';
 import Modal from '../components/ui/Modal';
 import ConfirmDialog from '../components/ui/ConfirmDialog';
 import DailyStatusForm from '../components/DailyStatusForm';
+import SubjectInfoForm from '../components/SubjectInfoForm';
 import Alert from '../components/ui/Alert';
 import AuditLogSection from '../components/AuditLogSection';
+import { SubjectAnalysisCharts } from '../components/AnalysisCharts';
+
+/** Read the value for a template field from a status record.
+ *  Custom fields are keyed by fieldId, not by the display key. */
+function getFieldValue(status, field) {
+  if (field.builtin) return status[field.key];
+  return status.custom_fields?.[field.fieldId];
+}
+
+// ── Inline cell editor ─────────────────────────────────────────────────────────
+
+function InlineCell({ statusId, field, value, currentStatus, onSaved }) {
+  const [editing, setEditing]     = useState(false);
+  const [draft, setDraft]         = useState('');
+  const [saving, setSaving]       = useState(false);
+  const [saveError, setSaveError] = useState(null);
+  const inputRef = useRef(null);
+  const isTextarea = field.type === 'textarea';
+
+  function startEdit(e) {
+    e.preventDefault();
+    e.stopPropagation();
+    setDraft(value ?? '');
+    setSaveError(null);
+    setEditing(true);
+  }
+
+  useEffect(() => {
+    if (editing && inputRef.current) {
+      inputRef.current.focus();
+      if (inputRef.current.select) inputRef.current.select();
+    }
+  }, [editing]);
+
+  async function commit() {
+    setEditing(false);
+    const newValue = draft.trim() || null;
+    if (newValue === (value?.trim() || null)) return;
+    setSaving(true);
+    setSaveError(null);
+    try {
+      let body;
+      if (field.builtin) {
+        body = { [field.key]: newValue };
+      } else {
+        body = { custom_fields: { ...currentStatus.custom_fields, [field.fieldId]: newValue } };
+      }
+      const updated = await dailyStatusesApi.update(statusId, body);
+      onSaved(updated);
+    } catch (err) {
+      setSaveError(err.message ?? 'Save failed');
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  function cancel() { setEditing(false); }
+
+  if (editing) {
+    const sharedProps = {
+      ref: inputRef,
+      value: draft,
+      onChange: (e) => setDraft(e.target.value),
+      onBlur: commit,
+      onClick: (e) => e.stopPropagation(),
+      onKeyDown: (e) => {
+        if (e.key === 'Escape') { e.preventDefault(); cancel(); }
+        if (e.key === 'Enter' && !isTextarea) { e.preventDefault(); commit(); }
+      },
+      className: 'w-full border border-indigo-400 rounded px-1.5 py-0.5 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-300 bg-white',
+    };
+    return isTextarea
+      ? <textarea {...sharedProps} rows={3} className={sharedProps.className + ' resize-none'} />
+      : <input type="text" {...sharedProps} />;
+  }
+
+  return (
+    <div
+      onDoubleClick={startEdit}
+      title={editing ? '' : 'Double-click to edit'}
+      className={`min-h-[1.25rem] cursor-default rounded transition-colors px-0.5 -mx-0.5
+        ${saving ? 'opacity-40' : 'hover:bg-indigo-50/60 group/ic'}`}
+    >
+      {saveError
+        ? <span className="text-red-500 text-xs">{saveError}</span>
+        : value
+          ? isTextarea
+            ? <span className="line-clamp-2 whitespace-pre-wrap">{value}</span>
+            : <span className="truncate block">{value}</span>
+          : <span className="text-gray-200 group-hover/ic:text-gray-400 select-none text-xs">· · ·</span>
+      }
+    </div>
+  );
+}
 
 export default function AnimalDetail() {
   const { id } = useParams();
   const navigate = useNavigate();
+  const location = useLocation();
 
   const [animal, setAnimal] = useState(null);
   const [statuses, setStatuses] = useState([]);
+  const [template, setTemplate] = useState([]);
+  const [subjectTemplate, setSubjectTemplate] = useState([]);
+  const [showSubjectInfo, setShowSubjectInfo] = useState(false);
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState(null);
   const [successMsg, setSuccessMsg] = useState(null);
@@ -23,6 +122,40 @@ export default function AnimalDetail() {
   const [editStatus, setEditStatus] = useState(null);
   const [deleteStatus, setDeleteStatus] = useState(null);
   const [deleteLoading, setDeleteLoading] = useState(false);
+  const [showDeleteSubject, setShowDeleteSubject] = useState(false);
+  const [deleteSubjectLoading, setDeleteSubjectLoading] = useState(false);
+  const [fillingGaps, setFillingGaps] = useState(false);
+
+  // Column visibility — persisted per experiment
+  const [hiddenCols, setHiddenCols] = useState(new Set());
+  const [showColPicker, setShowColPicker] = useState(false);
+  const colPickerRef = useRef(null);
+
+  useEffect(() => {
+    if (!animal) return;
+    const stored = localStorage.getItem(`col-vis-${animal.id}`);
+    setHiddenCols(stored ? new Set(JSON.parse(stored)) : new Set());
+  }, [animal?.id]);
+
+  function toggleCol(fieldId) {
+    setHiddenCols((prev) => {
+      const next = new Set(prev);
+      next.has(fieldId) ? next.delete(fieldId) : next.add(fieldId);
+      localStorage.setItem(`col-vis-${animal.id}`, JSON.stringify([...next]));
+      return next;
+    });
+  }
+
+  useEffect(() => {
+    if (!showColPicker) return;
+    function handleClick(e) {
+      if (colPickerRef.current && !colPickerRef.current.contains(e.target)) {
+        setShowColPicker(false);
+      }
+    }
+    document.addEventListener('mousedown', handleClick);
+    return () => document.removeEventListener('mousedown', handleClick);
+  }, [showColPicker]);
 
   async function load() {
     setLoading(true);
@@ -34,6 +167,13 @@ export default function AnimalDetail() {
       ]);
       setAnimal(animalData);
       setStatuses(statusData);
+
+      const [tmpl, subjTmpl] = await Promise.all([
+        experimentsApi.getTemplate(animalData.experiment_id),
+        experimentsApi.getSubjectTemplate(animalData.experiment_id),
+      ]);
+      setTemplate(tmpl);
+      setSubjectTemplate(subjTmpl);
     } catch (err) {
       setError(err.message);
     } finally {
@@ -60,6 +200,7 @@ export default function AnimalDetail() {
     try {
       await dailyStatusesApi.delete(deleteStatus.id);
       setDeleteStatus(null);
+      setEditStatus(null);
       load();
       flash('Daily status removed.');
     } catch (err) {
@@ -70,7 +211,33 @@ export default function AnimalDetail() {
     }
   }
 
-  if (loading) return <div className="max-w-5xl mx-auto px-4 py-8 text-gray-400">Loading…</div>;
+  async function fillGaps() {
+    setFillingGaps(true);
+    try {
+      await Promise.all(missingDates.map((date) => dailyStatusesApi.create({ date, animal_id: id })));
+      load();
+      flash(`Created ${missingDates.length} missing entr${missingDates.length === 1 ? 'y' : 'ies'}.`);
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setFillingGaps(false);
+    }
+  }
+
+  async function handleDeleteSubject() {
+    setDeleteSubjectLoading(true);
+    try {
+      await animalsApi.delete(animal.id);
+      navigate(`/experiments/${animal.experiment_id}`, { replace: true });
+    } catch (err) {
+      setError(err.message);
+      setShowDeleteSubject(false);
+    } finally {
+      setDeleteSubjectLoading(false);
+    }
+  }
+
+  if (loading) return <div className="max-w-5xl mx-auto px-4 py-8 text-gray-400" aria-live="polite" aria-busy="true">Loading…</div>;
   if (error) return (
     <div className="max-w-5xl mx-auto px-4 py-8">
       <Alert type="error" message={error} />
@@ -78,15 +245,32 @@ export default function AnimalDetail() {
     </div>
   );
 
+  const activeFields = template.filter((f) => f.active);
+  const visibleFields = activeFields.filter((f) => !hiddenCols.has(f.fieldId));
+
+  // Dates with entries
+  const existingDateSet = new Set(statuses.map((s) => String(s.date).slice(0, 10)));
+  const missingDates = (() => {
+    if (statuses.length < 2) return [];
+    const sorted = [...existingDateSet].sort();
+    const missing = [];
+    const cur = new Date(sorted[0] + 'T12:00:00');
+    const end = new Date(sorted[sorted.length - 1] + 'T12:00:00');
+    while (cur < end) {
+      cur.setDate(cur.getDate() + 1);
+      const d = cur.toISOString().slice(0, 10);
+      if (!existingDateSet.has(d)) missing.push(d);
+    }
+    return missing;
+  })();
+
   return (
     <div className="max-w-5xl mx-auto px-4 py-8">
       {/* Breadcrumb */}
       <nav className="text-sm text-gray-500 mb-4">
         <Link to="/" className="hover:text-blue-600">Experiments</Link>
         <span className="mx-2">/</span>
-        <Link to={`/experiments/${animal.experiment_id}`} className="hover:text-blue-600">
-          Experiment
-        </Link>
+        <Link to={`/experiments/${animal.experiment_id}`} className="hover:text-blue-600">Experiment</Link>
         <span className="mx-2">/</span>
         <span className="text-gray-900 font-medium">{animal.animal_name}</span>
       </nav>
@@ -106,69 +290,267 @@ export default function AnimalDetail() {
       {successMsg && <Alert type="success" message={successMsg} />}
       {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
 
+      {/* Subject information card */}
+      {subjectTemplate.filter((f) => f.active).length > 0 && (
+        <div className="bg-white border border-gray-200 rounded-xl p-5 mb-6">
+          <div className="flex items-center justify-between mb-3">
+            <h2 className="text-sm font-semibold text-gray-700 uppercase tracking-wide">Subject Information</h2>
+            <button
+              type="button"
+              onClick={() => setShowSubjectInfo(true)}
+              className="text-xs text-gray-400 hover:text-blue-600 transition-colors inline-flex items-center gap-1"
+            >
+              <svg className="w-3.5 h-3.5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15.232 5.232l3.536 3.536M9 13l6.586-6.586a2 2 0 112.828 2.828L11.828 15.828A2 2 0 0110 16.414V19h2.586a2 2 0 001.414-.586l6.5-6.5" />
+              </svg>
+              Edit
+            </button>
+          </div>
+          {(() => {
+            const filled = subjectTemplate.filter((f) => f.active && animal.subject_info?.[f.fieldId]);
+            if (filled.length === 0) {
+              return (
+                <button
+                  type="button"
+                  onClick={() => setShowSubjectInfo(true)}
+                  className="text-sm text-gray-400 italic hover:text-blue-600 transition-colors"
+                >
+                  No information recorded yet — click to add
+                </button>
+              );
+            }
+            return (
+              <dl className="grid grid-cols-1 sm:grid-cols-2 gap-x-6 gap-y-2 text-sm">
+                {filled.map((f) => (
+                  <div key={f.fieldId} className={f.type === 'textarea' ? 'sm:col-span-2' : ''}>
+                    <dt className="text-xs font-medium text-gray-500 uppercase tracking-wide">{f.label}</dt>
+                    <dd className="text-gray-800 mt-0.5 whitespace-pre-wrap">{animal.subject_info[f.fieldId]}</dd>
+                  </div>
+                ))}
+              </dl>
+            );
+          })()}
+        </div>
+      )}
+
       {statuses.length === 0 ? (
         <div className="text-center py-16 border-2 border-dashed border-gray-200 rounded-xl">
           <p className="text-gray-400 mb-3">No daily statuses logged yet.</p>
           <Button onClick={() => setShowAddStatus(true)}>+ Log First Status</Button>
         </div>
       ) : (
-        <div className="space-y-3">
-          {statuses.map((s) => (
-            <div key={s.id} className="bg-white border border-gray-200 rounded-xl p-5">
-              <div className="flex items-center justify-between mb-3">
-                <span className="font-semibold text-gray-900">
-                  {format(new Date(s.date), 'MMMM d, yyyy')}
-                </span>
-                <div className="flex gap-2">
-                  <Button size="sm" variant="secondary" onClick={() => setEditStatus(s)}>Edit</Button>
-                  <Button size="sm" variant="danger" onClick={() => setDeleteStatus(s)}>Delete</Button>
-                </div>
+        <div className="border border-gray-200 rounded-xl overflow-hidden">
+          {/* Column picker toolbar */}
+          {activeFields.length > 0 && (
+            <div className="flex justify-end px-3 py-1.5 border-b border-gray-100 bg-gray-50/60">
+              <div className="relative" ref={colPickerRef}>
+                <button
+                  type="button"
+                  onClick={() => setShowColPicker((v) => !v)}
+                  className="inline-flex items-center gap-1 text-xs text-gray-500 hover:text-gray-800 px-2 py-1 rounded hover:bg-gray-100 transition-colors"
+                >
+                  <svg className="w-3.5 h-3.5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+                    <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 17V7m0 10a2 2 0 01-2 2H5a2 2 0 01-2-2V7a2 2 0 012-2h2a2 2 0 012 2m0 10a2 2 0 002 2h2a2 2 0 002-2M9 7a2 2 0 012-2h2a2 2 0 012 2m0 10V7m0 10a2 2 0 002 2h2a2 2 0 002-2V7a2 2 0 00-2-2h-2a2 2 0 00-2 2" />
+                  </svg>
+                  Columns
+                  {hiddenCols.size > 0 && (
+                    <span className="ml-0.5 bg-indigo-100 text-indigo-700 rounded-full px-1.5 py-px text-[10px] font-medium leading-none">
+                      {activeFields.length - hiddenCols.size}/{activeFields.length}
+                    </span>
+                  )}
+                </button>
+                {showColPicker && (
+                  <div className="absolute right-0 top-full mt-1 z-30 bg-white border border-gray-200 rounded-lg shadow-lg p-2 min-w-[180px]">
+                    <p className="text-[10px] font-semibold text-gray-400 uppercase tracking-wide px-1 mb-1">Show / hide columns</p>
+                    {activeFields.map((f) => {
+                      const visible = !hiddenCols.has(f.fieldId);
+                      return (
+                        <label key={f.fieldId} className="flex items-center gap-2 px-1 py-0.5 rounded hover:bg-gray-50 cursor-pointer select-none text-xs text-gray-700">
+                          <input
+                            type="checkbox"
+                            checked={visible}
+                            onChange={() => toggleCol(f.fieldId)}
+                            className="w-3.5 h-3.5 accent-indigo-600"
+                          />
+                          <span className="truncate" title={f.label}>{f.label}</span>
+                        </label>
+                      );
+                    })}
+                    {hiddenCols.size > 0 && (
+                      <button
+                        type="button"
+                        onClick={() => {
+                          setHiddenCols(new Set());
+                          localStorage.removeItem(`col-vis-${animal.id}`);
+                        }}
+                        className="mt-1 w-full text-left text-[10px] text-indigo-500 hover:text-indigo-700 px-1 py-0.5"
+                      >
+                        Show all
+                      </button>
+                    )}
+                  </div>
+                )}
               </div>
-              <dl className="grid grid-cols-1 sm:grid-cols-2 gap-x-6 gap-y-2 text-sm">
-                {[
-                  ['Experiment Description', s.experiment_description],
-                  ['Vitals', s.vitals],
-                  ['Treatment', s.treatment],
-                  ['Notes', s.notes],
-                ]
-                  .filter(([, v]) => v)
-                  .map(([label, value]) => (
-                    <div key={label} className="flex flex-col">
-                      <dt className="text-xs font-medium text-gray-500 uppercase tracking-wide">{label}</dt>
-                      <dd className="text-gray-800 mt-0.5 whitespace-pre-wrap">{value}</dd>
-                    </div>
-                  ))}
-              </dl>
-              {!s.experiment_description && !s.vitals && !s.treatment && !s.notes && (
-                <p className="text-sm text-gray-400 italic">No details recorded for this date.</p>
-              )}
             </div>
-          ))}
+          )}
+
+          <div className="overflow-x-auto">
+            <table className="text-sm border-collapse min-w-full">
+              <thead>
+                <tr className="bg-gray-50 border-b border-gray-200">
+                  <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide whitespace-nowrap sticky left-0 bg-gray-50 z-10 border-r border-gray-200 min-w-[110px]">
+                    Date
+                  </th>
+                  {visibleFields.map((f) => {
+                    const header = f.abbr ? (f.unit ? `${f.abbr} (${f.unit})` : f.abbr) : (f.unit ? `${f.label} (${f.unit})` : f.label);
+                    const tooltip = f.unit ? `${f.label} (${f.unit})` : f.label;
+                    const minW = Math.max(80, header.length * 7.5 + 24);
+                    return (
+                      <th key={f.key} title={tooltip} style={{ minWidth: minW }} className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide whitespace-nowrap max-w-[220px] cursor-default">
+                        {header}
+                      </th>
+                    );
+                  })}
+                  {activeFields.length === 0 && (
+                    <>
+                      {['Experiment Description', 'Vitals', 'Treatment', 'Notes'].map((l) => (
+                        <th key={l} className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide whitespace-nowrap min-w-[120px]">{l}</th>
+                      ))}
+                    </>
+                  )}
+                  <th className="sticky right-0 bg-gray-50 z-10 border-l border-gray-200 px-3 py-2 min-w-[96px]" />
+                </tr>
+              </thead>
+              <tbody>
+                {statuses.map((s, i) => {
+                  const rowBg = i % 2 === 0 ? 'bg-white' : 'bg-gray-50/40';
+                  const renderFields = activeFields.length > 0 ? visibleFields : [
+                    { fieldId: '__exp_desc__', key: 'experiment_description', label: 'Experiment Description', type: 'textarea', builtin: true, active: true },
+                    { fieldId: '__vitals__',   key: 'vitals',                 label: 'Vitals',                 type: 'text',     builtin: true, active: true },
+                    { fieldId: '__treatment__',key: 'treatment',              label: 'Treatment',              type: 'text',     builtin: true, active: true },
+                    { fieldId: '__notes__',    key: 'notes',                  label: 'Notes',                  type: 'textarea', builtin: true, active: true },
+                  ];
+                  return (
+                    <tr key={s.id} className={`border-b border-gray-100 last:border-0 ${rowBg}`}>
+                      <td
+                        className={`px-3 py-2 font-medium text-gray-700 whitespace-nowrap sticky left-0 z-10 border-r border-gray-100 cursor-pointer hover:text-blue-600 hover:bg-blue-50/40 transition-colors ${rowBg}`}
+                        onClick={() => navigate(`/daily-statuses/${s.id}`)}
+                      >
+                        {format(new Date(String(s.date).slice(0, 10) + 'T12:00:00'), 'MMM d, yyyy')}
+                      </td>
+                      {renderFields.map((f) => (
+                        <td key={f.fieldId} className="px-3 py-1.5 text-gray-700 max-w-[220px]">
+                          <InlineCell
+                            statusId={s.id}
+                            field={f}
+                            value={getFieldValue(s, f)}
+                            currentStatus={s}
+                            onSaved={(updated) => setStatuses((prev) => prev.map((x) => x.id === s.id ? { ...x, ...updated } : x))}
+                          />
+                        </td>
+                      ))}
+                      <td className={`px-2 py-1.5 sticky right-0 z-10 border-l border-gray-100 ${rowBg}`}>
+                        <div className="flex gap-1 justify-end">
+                          <Button size="sm" variant="secondary" onClick={() => setEditStatus(s)}>Edit</Button>
+                        </div>
+                      </td>
+                    </tr>
+                  );
+                })}
+              </tbody>
+            </table>
+          </div>
         </div>
       )}
 
-      <AuditLogSection tableName="daily_statuses" recordId={undefined} />
+      {missingDates.length > 0 && (
+        <div className="mt-3 flex items-center justify-between px-4 py-3 bg-amber-50 border border-amber-200 rounded-xl">
+          <p className="text-sm text-amber-800">
+            <span className="font-semibold">{missingDates.length}</span> date{missingDates.length !== 1 ? 's' : ''} between the earliest and latest entries have no record.
+          </p>
+          <Button variant="secondary" size="sm" onClick={fillGaps} loading={fillingGaps}>
+            Create {missingDates.length} empty entr{missingDates.length === 1 ? 'y' : 'ies'}
+          </Button>
+        </div>
+      )}
 
-      <Modal isOpen={showAddStatus} onClose={() => setShowAddStatus(false)} title="Log Daily Status" size="lg">
-        <DailyStatusForm animalId={id} onSuccess={handleStatusSaved} onCancel={() => setShowAddStatus(false)} />
-      </Modal>
+      <SubjectAnalysisCharts statuses={statuses} dailyTemplate={template} />
 
-      <Modal isOpen={!!editStatus} onClose={() => setEditStatus(null)} title="Edit Daily Status" size="lg">
-        <DailyStatusForm
-          existing={editStatus}
-          animalId={id}
-          onSuccess={handleStatusSaved}
-          onCancel={() => setEditStatus(null)}
+      <AuditLogSection tableName="daily_statuses" limit={5} />
+
+      {/* Danger zone */}
+      <div className="mt-10 border border-red-200 rounded-xl p-4 bg-red-50/40">
+        <h2 className="text-xs font-semibold text-red-600 uppercase tracking-wide mb-2">Danger Zone</h2>
+        <div className="flex items-center justify-between">
+          <p className="text-sm text-gray-600">Permanently delete this subject and all its daily status records.</p>
+          <Button variant="danger" onClick={() => setShowDeleteSubject(true)}>Delete Subject</Button>
+        </div>
+      </div>
+
+      <Modal isOpen={showSubjectInfo} onClose={() => setShowSubjectInfo(false)} title="Subject Information" size="full">
+        <SubjectInfoForm
+          animal={animal}
+          subjectTemplate={subjectTemplate}
+          experimentId={animal?.experiment_id}
+          onTemplateUpdate={setSubjectTemplate}
+          onSaved={(updated) => { setAnimal(updated); setShowSubjectInfo(false); flash('Subject information saved.'); }}
+          onCancel={() => setShowSubjectInfo(false)}
         />
       </Modal>
 
+      <Modal isOpen={showAddStatus} onClose={() => setShowAddStatus(false)} title="Log Daily Status" size="full">
+        <DailyStatusForm
+          animalId={id}
+          experimentId={animal?.experiment_id}
+          template={template}
+          onTemplateUpdate={setTemplate}
+          onSuccess={handleStatusSaved}
+          onCancel={() => setShowAddStatus(false)}
+        />
+      </Modal>
+
+      {(() => {
+        const editIdx = editStatus ? statuses.findIndex((s) => s.id === editStatus.id) : -1;
+        return (
+          <Modal isOpen={!!editStatus} onClose={() => setEditStatus(null)} title="Edit Daily Status" size="full">
+            <DailyStatusForm
+              existing={editStatus}
+              animalId={id}
+              experimentId={animal?.experiment_id}
+              template={template}
+              onTemplateUpdate={setTemplate}
+              onSuccess={handleStatusSaved}
+              onCancel={() => setEditStatus(null)}
+              onRequestDelete={() => setDeleteStatus(editStatus)}
+              hasPrev={editIdx > 0}
+              hasNext={editIdx < statuses.length - 1}
+              onNavigate={(direction, savedResult) => {
+                setStatuses((prev) => prev.map((s) => s.id === savedResult.id ? savedResult : s));
+                setEditStatus(statuses[direction === 'prev' ? editIdx - 1 : editIdx + 1]);
+              }}
+            />
+          </Modal>
+        );
+      })()}
+
       <ConfirmDialog
         isOpen={!!deleteStatus}
         onClose={() => setDeleteStatus(null)}
         onConfirm={handleDeleteStatus}
         loading={deleteLoading}
         title="Delete Daily Status"
-        message={`Delete the status entry for ${deleteStatus ? format(new Date(deleteStatus.date), 'MMMM d, yyyy') : ''}?`}
+        message={`Delete the status entry for ${deleteStatus ? format(new Date(String(deleteStatus.date).slice(0, 10) + 'T12:00:00'), 'MMMM d, yyyy') : ''}? This cannot be undone.`}
+        confirmWord="delete"
+      />
+
+      <ConfirmDialog
+        isOpen={showDeleteSubject}
+        onClose={() => setShowDeleteSubject(false)}
+        onConfirm={handleDeleteSubject}
+        loading={deleteSubjectLoading}
+        title="Delete Subject"
+        message={`This will permanently delete "${animal.animal_name}" and all ${statuses.length} daily status record${statuses.length !== 1 ? 's' : ''}. This cannot be undone.`}
+        confirmWord="delete"
       />
     </div>
   );

frontend/src/pages/DailyStatusDetail.jsx

@@ -0,0 +1,764 @@
+import React, { useEffect, useState } from 'react';
+import { useParams, useNavigate, Link } from 'react-router-dom';
+import { format } from 'date-fns';
+import { dailyStatusesApi, experimentsApi, analysesApi } from '../api/client';
+import Button from '../components/ui/Button';
+import Modal from '../components/ui/Modal';
+import ConfirmDialog from '../components/ui/ConfirmDialog';
+import DailyStatusForm from '../components/DailyStatusForm';
+import Alert from '../components/ui/Alert';
+import CsvAnalysis from '../components/CsvAnalysis';
+import AuditLogSection from '../components/AuditLogSection';
+import RunSequenceView from '../components/RunSequenceView';
+import FileDropZone from '../components/FileDropZone';
+
+function fmtDate(raw) {
+  return format(new Date(String(raw).slice(0, 10) + 'T12:00:00'), 'MMMM d, yyyy');
+}
+
+function fmtDateTime(raw) {
+  return format(new Date(raw), 'MMM d, yyyy · h:mm a');
+}
+
+function getFieldValue(status, field) {
+  if (field.builtin) return status[field.key];
+  return status.custom_fields?.[field.fieldId];
+}
+
+// ── Analysis summary card ─────────────────────────────────────────────────────
+
+function AnalysisSummaryCard({ summary, statusId, onSummaryUpdated }) {
+  const { counts = {}, total, success_rate, computed_at } = summary;
+  const COLORS = {
+    Success: 'bg-green-100 text-green-800',
+    Failure: 'bg-red-100 text-red-800',
+    Other:   'bg-gray-100 text-gray-700',
+  };
+  const EXTRA = ['bg-indigo-100 text-indigo-800', 'bg-yellow-100 text-yellow-800', 'bg-purple-100 text-purple-800', 'bg-pink-100 text-pink-800'];
+  const catList = Object.entries(counts).sort(([, a], [, b]) => b - a);
+  let extraIdx = 0;
+
+  const [showForm, setShowForm] = useState(false);
+
+  return (
+    <div className="bg-white border border-gray-200 rounded-xl px-5 py-4 mb-6">
+      <div className="flex items-center justify-between mb-3">
+        <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide">Session metrics</p>
+        <div className="flex items-center gap-3">
+          {computed_at && <p className="text-[10px] text-gray-400">Updated {fmtDateTime(computed_at)}</p>}
+          {!showForm && (
+            <button
+              type="button"
+              onClick={() => setShowForm(true)}
+              className="text-[10px] text-gray-400 hover:text-indigo-600 border border-dashed border-gray-200 hover:border-indigo-300 rounded px-2 py-0.5 transition-colors"
+            >
+              Edit manually
+            </button>
+          )}
+        </div>
+      </div>
+
+      {showForm ? (
+        <ManualMetricsForm
+          statusId={statusId}
+          existing={summary}
+          onSaved={(updated) => {
+            onSummaryUpdated({ ...updated, computed_at: new Date().toISOString() });
+            setShowForm(false);
+          }}
+          onClose={() => setShowForm(false)}
+        />
+      ) : (
+        <div className="flex flex-wrap gap-3 items-center">
+          {catList.map(([cat, n]) => {
+            const cls = COLORS[cat] ?? EXTRA[extraIdx++ % EXTRA.length];
+            return (
+              <div key={cat} className={`flex flex-col items-center px-3 py-2 rounded-lg ${cls}`}>
+                <span className="text-xs font-medium">{cat}</span>
+                <span className="text-xl font-bold leading-tight">{n}</span>
+              </div>
+            );
+          })}
+          <div className="flex flex-col items-center px-3 py-2 rounded-lg bg-blue-50 text-blue-800">
+            <span className="text-xs font-medium">Total</span>
+            <span className="text-xl font-bold leading-tight">{total}</span>
+          </div>
+          {success_rate != null && (
+            <div className="flex flex-col items-center px-3 py-2 rounded-lg bg-indigo-50 text-indigo-800">
+              <span className="text-xs font-medium">Success rate</span>
+              <span className="text-xl font-bold leading-tight">{(success_rate * 100).toFixed(1)}%</span>
+            </div>
+          )}
+        </div>
+      )}
+    </div>
+  );
+}
+
+// ── Manual metrics form ───────────────────────────────────────────────────────
+
+const DEFAULT_CATS = ['Success', 'Failure', 'Other'];
+
+function ManualMetricsForm({ statusId, existing, onSaved, onClose }) {
+  const initCounts = () => {
+    const base = { ...existing?.counts };
+    for (const c of DEFAULT_CATS) if (!(c in base)) base[c] = 0;
+    return base;
+  };
+
+  const [counts, setCounts] = useState(initCounts);
+  const [newCat, setNewCat] = useState('');
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState(null);
+
+  const total = Object.values(counts).reduce((a, b) => a + (Number(b) || 0), 0);
+  const successRate = total > 0 && counts['Success'] != null
+    ? (Number(counts['Success']) || 0) / total
+    : null;
+
+  function setCount(cat, raw) {
+    const v = Math.max(0, parseInt(raw, 10) || 0);
+    setCounts((prev) => ({ ...prev, [cat]: v }));
+  }
+
+  function addCat() {
+    const name = newCat.trim();
+    if (!name || name in counts) return;
+    setCounts((prev) => ({ ...prev, [name]: 0 }));
+    setNewCat('');
+  }
+
+  function removeCat(cat) {
+    if (DEFAULT_CATS.includes(cat)) return;
+    setCounts((prev) => { const n = { ...prev }; delete n[cat]; return n; });
+  }
+
+  async function save() {
+    setSaving(true);
+    setError(null);
+    try {
+      const finalCounts = Object.fromEntries(
+        Object.entries(counts).map(([k, v]) => [k, Number(v) || 0])
+      );
+      await dailyStatusesApi.updateAnalysisSummary(statusId, {
+        counts: finalCounts,
+        total,
+        success_rate: successRate,
+        source_analysis_id: null,
+      });
+      onSaved({ counts: finalCounts, total, success_rate: successRate });
+    } catch (err) {
+      setError(err.message ?? 'Failed to save');
+    } finally {
+      setSaving(false);
+    }
+  }
+
+  return (
+    <div className="bg-white border border-gray-200 rounded-xl px-5 py-4 mb-6">
+      <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-3">Set metrics manually</p>
+      <div className="flex flex-wrap gap-3 items-end mb-3">
+        {Object.entries(counts).map(([cat, val]) => (
+          <div key={cat} className="flex flex-col items-center gap-1">
+            <span className="text-xs text-gray-500">{cat}</span>
+            <input
+              type="number" min={0} value={val}
+              onChange={(e) => setCount(cat, e.target.value)}
+              className="w-20 text-center border border-gray-300 rounded px-2 py-1 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-400"
+            />
+            {!DEFAULT_CATS.includes(cat) && (
+              <button type="button" onClick={() => removeCat(cat)}
+                className="text-[10px] text-red-400 hover:text-red-600">remove</button>
+            )}
+          </div>
+        ))}
+
+        {/* Add custom category inline */}
+        <div className="flex flex-col items-center gap-1">
+          <span className="text-xs text-gray-400">+ category</span>
+          <div className="flex gap-1">
+            <input value={newCat} onChange={(e) => setNewCat(e.target.value)}
+              onKeyDown={(e) => { if (e.key === 'Enter') addCat(); }}
+              placeholder="Name…"
+              className="w-24 border border-dashed border-gray-300 rounded px-2 py-1 text-xs focus:outline-none focus:ring-1 focus:ring-indigo-400" />
+            <button type="button" onClick={addCat}
+              className="text-xs text-indigo-500 hover:text-indigo-700 px-1">Add</button>
+          </div>
+        </div>
+      </div>
+
+      <div className="flex items-center gap-4 text-xs text-gray-500 mb-3">
+        <span>Total: <strong className="text-gray-800">{total}</strong></span>
+        {successRate != null && (
+          <span>Success rate: <strong className="text-gray-800">{(successRate * 100).toFixed(1)}%</strong></span>
+        )}
+      </div>
+
+      {error && <p className="text-xs text-red-500 mb-2">{error}</p>}
+      <div className="flex gap-2">
+        <button type="button" onClick={save} disabled={saving}
+          className="px-3 py-1.5 rounded-lg text-sm font-medium bg-indigo-600 text-white hover:bg-indigo-700 disabled:opacity-50 transition-colors">
+          {saving ? 'Saving…' : 'Save'}
+        </button>
+        <button type="button" onClick={onClose}
+          className="px-3 py-1.5 rounded-lg text-sm text-gray-500 hover:text-gray-700 border border-gray-200 transition-colors">
+          Cancel
+        </button>
+      </div>
+    </div>
+  );
+}
+
+// ── Past analysis row (expandable) ────────────────────────────────────────────
+
+function AnalysisRow({ analysis, onDelete }) {
+  const [expanded, setExpanded] = useState(false);
+  const [full, setFull] = useState(null);
+  const [loadingFull, setLoadingFull] = useState(false);
+  const [confirmDelete, setConfirmDelete] = useState(false);
+  const [deleting, setDeleting] = useState(false);
+
+  async function expand() {
+    if (expanded) { setExpanded(false); return; }
+    setExpanded(true);
+    if (full) return;
+    setLoadingFull(true);
+    try {
+      const data = await analysesApi.get(analysis.id);
+      setFull(data);
+    } finally {
+      setLoadingFull(false);
+    }
+  }
+
+  async function handleDelete() {
+    setDeleting(true);
+    try {
+      await analysesApi.delete(analysis.id);
+      onDelete(analysis.id);
+    } finally {
+      setDeleting(false);
+    }
+  }
+
+  const counts = analysis.category_counts ?? {};
+  const summary = Object.entries(counts)
+    .sort(([, a], [, b]) => b.total - a.total)
+    .map(([cat, d]) => `${cat}: ${d.total}`)
+    .join(' · ');
+
+  return (
+    <div className="border border-gray-200 rounded-lg overflow-hidden">
+      <div
+        className="flex items-center justify-between px-4 py-3 cursor-pointer hover:bg-gray-50 transition-colors"
+        onClick={expand}
+      >
+        <div className="flex items-center gap-3 min-w-0">
+          <span className="text-gray-400 text-xs">{expanded ? '▾' : '▸'}</span>
+          <div className="min-w-0">
+            <p className="text-sm font-medium text-gray-800 truncate">
+              {analysis.file_name ?? 'Unnamed file'}
+            </p>
+            <p className="text-xs text-gray-400">
+              {fmtDateTime(analysis.created_at)}
+              {' · '}
+              <span className="font-mono">{analysis.note_col}</span>
+              {' · '}
+              {analysis.total_note_rows} note rows
+            </p>
+          </div>
+        </div>
+        <div className="flex items-center gap-3 ml-4 shrink-0">
+          <span className="text-xs text-gray-500 hidden sm:block">{summary}</span>
+          <button type="button" onClick={(e) => { e.stopPropagation(); setConfirmDelete(true); }}
+            className="text-xs text-red-400 hover:text-red-600 transition-colors">Delete</button>
+        </div>
+      </div>
+
+      {expanded && (
+        <div className="border-t border-gray-100 px-4 py-4 bg-gray-50/40">
+          {loadingFull && <p className="text-sm text-gray-400">Loading…</p>}
+          {full && <AnalysisResultsView analysis={full} />}
+        </div>
+      )}
+
+      <ConfirmDialog
+        isOpen={confirmDelete}
+        onClose={() => setConfirmDelete(false)}
+        onConfirm={handleDelete}
+        loading={deleting}
+        title="Delete Analysis"
+        message="Remove this analysis record? The raw CSV is not affected."
+      />
+    </div>
+  );
+}
+
+// ── Analysis results display (reused by both live and past) ───────────────────
+
+export function AnalysisResultsView({ analysis }) {
+  const { timestamp_col, note_col, total_note_rows,
+          category_counts, consecutive_stats, runs } = analysis;
+  const customCategories = [];
+
+  function colorsFor(cat) {
+    const COLORS = {
+      Success: { bg: 'bg-green-100', text: 'text-green-800', dot: 'bg-green-500', border: 'border-green-300' },
+      Failure: { bg: 'bg-red-100',   text: 'text-red-800',   dot: 'bg-red-500',   border: 'border-red-300'   },
+      Other:   { bg: 'bg-gray-100',  text: 'text-gray-700',  dot: 'bg-gray-400',  border: 'border-gray-300'  },
+    };
+    const EXTRA = [
+      { bg: 'bg-indigo-100', text: 'text-indigo-800', dot: 'bg-indigo-500', border: 'border-indigo-300' },
+      { bg: 'bg-yellow-100', text: 'text-yellow-800', dot: 'bg-yellow-500', border: 'border-yellow-300' },
+      { bg: 'bg-purple-100', text: 'text-purple-800', dot: 'bg-purple-500', border: 'border-purple-300' },
+    ];
+    if (COLORS[cat]) return COLORS[cat];
+    const idx = customCategories.indexOf(cat) % EXTRA.length;
+    return EXTRA[Math.max(0, idx)];
+  }
+
+  return (
+    <div className="space-y-5 text-sm">
+      <p className="text-xs text-gray-400">
+        {total_note_rows} note rows · timestamp: <span className="font-mono">{timestamp_col}</span>
+        {' '}/ note: <span className="font-mono">{note_col}</span>
+      </p>
+
+      {/* Category counts */}
+      <div>
+        <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1.5">Category Counts</p>
+        <table className="w-full border-collapse text-sm">
+          <thead>
+            <tr className="bg-white border-b border-gray-200">
+              <th className="text-left px-3 py-1.5 text-xs font-semibold text-gray-500">Category</th>
+              <th className="text-left px-3 py-1.5 text-xs font-semibold text-gray-500">Breakdown</th>
+              <th className="text-right px-3 py-1.5 text-xs font-semibold text-gray-500">Total</th>
+            </tr>
+          </thead>
+          <tbody>
+            {Object.entries(category_counts ?? {})
+              .sort(([, a], [, b]) => b.total - a.total)
+              .map(([cat, data]) => {
+                const c = colorsFor(cat);
+                const bd = Object.entries(data.byNote ?? {})
+                  .sort(([, a], [, b]) => b - a)
+                  .map(([n, cnt]) => `${n}: ${cnt}`).join(' · ');
+                return (
+                  <tr key={cat} className="border-b border-gray-100">
+                    <td className="px-3 py-1.5">
+                      <span className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-semibold ${c.bg} ${c.text}`}>
+                        <span className={`w-1.5 h-1.5 rounded-full ${c.dot}`} />
+                        {cat}
+                      </span>
+                    </td>
+                    <td className="px-3 py-1.5 text-gray-500 font-mono text-xs">{bd}</td>
+                    <td className="px-3 py-1.5 text-right font-semibold text-gray-800">{data.total}</td>
+                  </tr>
+                );
+              })}
+          </tbody>
+        </table>
+      </div>
+
+      {/* Consecutive stats */}
+      {Object.keys(consecutive_stats ?? {}).length > 0 && (
+        <div>
+          <p className="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1.5">Consecutive Runs</p>
+          <table className="w-full border-collapse text-sm">
+            <thead>
+              <tr className="bg-white border-b border-gray-200">
+                <th className="text-left px-3 py-1.5 text-xs font-semibold text-gray-500">Category</th>
+                <th className="text-right px-3 py-1.5 text-xs font-semibold text-gray-500">Runs</th>
+                <th className="text-right px-3 py-1.5 text-xs font-semibold text-gray-500">Max</th>
+                <th className="text-right px-3 py-1.5 text-xs font-semibold text-gray-500">Avg</th>
+                <th className="text-left px-3 py-1.5 text-xs font-semibold text-gray-500">Lengths</th>
+              </tr>
+            </thead>
+            <tbody>
+              {Object.entries(consecutive_stats).map(([cat, s]) => {
+                const c = colorsFor(cat);
+                const summary = Object.entries(
+                  s.runLengths.reduce((acc, l) => { acc[l] = (acc[l] || 0) + 1; return acc; }, {})
+                ).sort(([a], [b]) => Number(a) - Number(b))
+                  .map(([l, cnt]) => `${l}×${cnt}`).join(', ');
+                return (
+                  <tr key={cat} className="border-b border-gray-100">
+                    <td className="px-3 py-1.5">
+                      <span className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-semibold ${c.bg} ${c.text}`}>
+                        <span className={`w-1.5 h-1.5 rounded-full ${c.dot}`} />
+                        {cat}
+                      </span>
+                    </td>
+                    <td className="px-3 py-1.5 text-right text-gray-700">{s.totalRuns}</td>
+                    <td className="px-3 py-1.5 text-right text-gray-700">{s.maxRun}</td>
+                    <td className="px-3 py-1.5 text-right text-gray-700">{s.avgRun.toFixed(2)}</td>
+                    <td className="px-3 py-1.5 text-gray-500 font-mono text-xs">{summary}</td>
+                  </tr>
+                );
+              })}
+            </tbody>
+          </table>
+        </div>
+      )}
+
+      <RunSequenceView runs={runs ?? []} sequence={analysis.sequence ?? []} sessionEndTs={analysis.session_end_ts ?? null} />
+    </div>
+  );
+}
+
+// ── Past analyses inline viewer ───────────────────────────────────────────────
+
+function PastAnalysesViewer({ analyses, onDelete, onNewAnalysis }) {
+  const [selectedId, setSelectedId]   = useState(() => analyses[0]?.id ?? null);
+  const [cache, setCache]             = useState({});
+  const [loadingId, setLoadingId]     = useState(null);
+  const [confirmDelete, setConfirmDelete] = useState(null);
+  const [deleting, setDeleting]       = useState(false);
+
+  // Load full data whenever the selected id changes
+  useEffect(() => {
+    if (!selectedId || cache[selectedId]) return;
+    setLoadingId(selectedId);
+    analysesApi.get(selectedId)
+      .then((data) => setCache((prev) => ({ ...prev, [selectedId]: data })))
+      .catch(() => {})
+      .finally(() => setLoadingId(null));
+  }, [selectedId]);
+
+  // If the list changes (new analysis added / deleted), keep selection valid
+  useEffect(() => {
+    if (!analyses.length) { setSelectedId(null); return; }
+    if (!analyses.find((a) => a.id === selectedId)) setSelectedId(analyses[0].id);
+  }, [analyses]);
+
+  async function handleDelete(id) {
+    setDeleting(true);
+    try {
+      await analysesApi.delete(id);
+      setCache((prev) => { const n = { ...prev }; delete n[id]; return n; });
+      onDelete(id);
+    } finally {
+      setDeleting(false);
+      setConfirmDelete(null);
+    }
+  }
+
+  if (!analyses.length) return null;
+
+  const selected  = analyses.find((a) => a.id === selectedId) ?? null;
+  const fullData  = selectedId ? (cache[selectedId] ?? null) : null;
+  const isLoading = loadingId === selectedId;
+
+  const categorySummary = (a) =>
+    Object.entries(a.category_counts ?? {})
+      .sort(([, x], [, y]) => y.total - x.total)
+      .map(([cat, d]) => `${cat}: ${d.total}`)
+      .join(' · ');
+
+  return (
+    <div className="mt-8 border-t border-gray-200 pt-6">
+      {/* Header */}
+      <div className="flex items-center justify-between mb-4">
+        <h2 className="text-sm font-semibold text-gray-700 uppercase tracking-wide">
+          Past Analyses ({analyses.length})
+        </h2>
+      </div>
+
+      {/* Tab selector — scrollable if many */}
+      {analyses.length > 1 && (
+        <div className="flex gap-1.5 overflow-x-auto pb-2 mb-4 scrollbar-thin">
+          {analyses.map((a) => {
+            const active = a.id === selectedId;
+            return (
+              <button
+                key={a.id}
+                type="button"
+                onClick={() => setSelectedId(a.id)}
+                className={`shrink-0 flex flex-col items-start px-3 py-2 rounded-lg border text-left transition-colors
+                  ${active
+                    ? 'bg-indigo-50 border-indigo-300 text-indigo-800'
+                    : 'bg-white border-gray-200 text-gray-600 hover:border-gray-300 hover:bg-gray-50'}`}
+              >
+                <span className="text-xs font-medium truncate max-w-[160px]">
+                  {a.file_name ?? 'Unnamed file'}
+                </span>
+                <span className={`text-[10px] mt-0.5 ${active ? 'text-indigo-500' : 'text-gray-400'}`}>
+                  {fmtDateTime(a.created_at)}
+                </span>
+              </button>
+            );
+          })}
+        </div>
+      )}
+
+      {/* Selected analysis panel */}
+      {selected && (
+        <div className="bg-white border border-gray-200 rounded-xl overflow-hidden">
+          {/* Panel header */}
+          <div className="flex items-start justify-between px-4 py-3 border-b border-gray-100 bg-gray-50/50">
+            <div>
+              <p className="text-sm font-medium text-gray-800">
+                {selected.file_name ?? 'Unnamed file'}
+              </p>
+              <p className="text-xs text-gray-400 mt-0.5">
+                {fmtDateTime(selected.created_at)}
+                {' · '}
+                <span className="font-mono">{selected.note_col}</span>
+                {' · '}
+                {selected.total_note_rows} note rows
+                {categorySummary(selected) && (
+                  <span className="ml-2 text-gray-500">{categorySummary(selected)}</span>
+                )}
+              </p>
+            </div>
+            <button
+              type="button"
+              onClick={() => setConfirmDelete(selected.id)}
+              className="text-xs text-red-400 hover:text-red-600 transition-colors shrink-0 ml-4 mt-0.5"
+            >
+              Delete
+            </button>
+          </div>
+
+          {/* Panel body */}
+          <div className="px-4 py-4">
+            {isLoading && (
+              <p className="text-sm text-gray-400 py-4 text-center">Loading…</p>
+            )}
+            {!isLoading && fullData && <AnalysisResultsView analysis={fullData} />}
+          </div>
+        </div>
+      )}
+
+      <ConfirmDialog
+        isOpen={!!confirmDelete}
+        onClose={() => setConfirmDelete(null)}
+        onConfirm={() => handleDelete(confirmDelete)}
+        loading={deleting}
+        title="Delete Analysis"
+        message="Remove this analysis record? The raw CSV is not affected."
+      />
+    </div>
+  );
+}
+
+// ── Page ──────────────────────────────────────────────────────────────────────
+
+export default function DailyStatusDetail() {
+  const { id } = useParams();
+  const navigate = useNavigate();
+
+  const [status, setStatus] = useState(null);
+  const [template, setTemplate] = useState([]);
+  const [allStatuses, setAllStatuses] = useState([]);
+  const [analyses, setAnalyses] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+
+  const [showEdit, setShowEdit] = useState(false);
+  const [showDelete, setShowDelete] = useState(false);
+  const [deleteLoading, setDeleteLoading] = useState(false);
+  const [showManualForm, setShowManualForm] = useState(false);
+
+  async function load(statusId = id) {
+    setLoading(true);
+    setError(null);
+    try {
+      const s = await dailyStatusesApi.get(statusId);
+      const [tmpl, siblings, pastAnalyses] = await Promise.all([
+        experimentsApi.getTemplate(s.animal.experiment_id),
+        dailyStatusesApi.list(s.animal_id),
+        analysesApi.listForStatus(statusId),
+      ]);
+      setStatus(s);
+      setTemplate(tmpl);
+      setAllStatuses(siblings);
+      setAnalyses(pastAnalyses);
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  useEffect(() => { load(); }, [id]);
+
+  async function handleDelete() {
+    setDeleteLoading(true);
+    try {
+      await dailyStatusesApi.delete(status.id);
+      navigate(`/animals/${status.animal_id}`, { replace: true });
+    } catch (err) {
+      setError(err.message);
+      setShowDelete(false);
+    } finally {
+      setDeleteLoading(false);
+    }
+  }
+
+  if (loading) return <div className="max-w-3xl mx-auto px-4 py-8 text-gray-400">Loading…</div>;
+  if (error) return (
+    <div className="max-w-3xl mx-auto px-4 py-8">
+      <Alert type="error" message={error} />
+      <Button variant="secondary" className="mt-4" onClick={() => navigate(-1)}>← Back</Button>
+    </div>
+  );
+
+  const animal = status.animal;
+  const activeFields = template.filter((f) => f.active);
+
+  const currentIdx = allStatuses.findIndex((s) => s.id === status.id);
+  const prevStatus = currentIdx > 0 ? allStatuses[currentIdx - 1] : null;
+  const nextStatus = currentIdx < allStatuses.length - 1 ? allStatuses[currentIdx + 1] : null;
+
+  return (
+    <div className="max-w-3xl mx-auto px-4 py-8">
+      {/* Breadcrumb */}
+      <nav className="text-sm text-gray-500 mb-4">
+        <Link to="/" className="hover:text-blue-600">Experiments</Link>
+        <span className="mx-2">/</span>
+        <Link to={`/experiments/${animal.experiment_id}`} className="hover:text-blue-600">Experiment</Link>
+        <span className="mx-2">/</span>
+        <Link to={`/animals/${animal.id}`} className="hover:text-blue-600">{animal.animal_name}</Link>
+        <span className="mx-2">/</span>
+        <span className="text-gray-900 font-medium">{fmtDate(status.date)}</span>
+      </nav>
+
+      {/* Header */}
+      <div className="flex items-start justify-between mb-6">
+        <div>
+          <h1 className="text-2xl font-bold text-gray-900">{fmtDate(status.date)}</h1>
+          <p className="text-sm text-gray-500 mt-0.5">
+            {animal.animal_name}
+            {animal.animal_id_string && <> · <span className="font-mono">{animal.animal_id_string}</span></>}
+          </p>
+        </div>
+        <Button variant="secondary" onClick={() => setShowEdit(true)}>Edit entry</Button>
+      </div>
+
+      {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
+
+      {/* Field values */}
+      <div className="bg-white border border-gray-200 rounded-xl p-6 mb-6">
+        {activeFields.length === 0 ? (
+          <p className="text-sm text-gray-400 italic">No template fields configured.</p>
+        ) : (
+          <dl className="grid grid-cols-1 sm:grid-cols-2 gap-x-8 gap-y-4">
+            {activeFields.map((f) => {
+              const value = getFieldValue(status, f);
+              const label = f.unit ? `${f.label} (${f.unit})` : f.label;
+              return (
+                <div key={f.fieldId} className={f.type === 'textarea' ? 'sm:col-span-2' : ''}>
+                  <dt className="text-xs font-semibold text-gray-400 uppercase tracking-wide mb-0.5">{label}</dt>
+                  <dd className="text-gray-800 whitespace-pre-wrap break-words">
+                    {value ?? <span className="text-gray-300 italic">—</span>}
+                  </dd>
+                </div>
+              );
+            })}
+          </dl>
+        )}
+      </div>
+
+      {/* Analysis summary (pinned metrics) */}
+      {status.analysis_summary ? (
+        <AnalysisSummaryCard
+          summary={status.analysis_summary}
+          statusId={status.id}
+          onSummaryUpdated={(summary) => setStatus((prev) => ({ ...prev, analysis_summary: summary }))}
+        />
+      ) : (
+        <div className="mb-4">
+          <button
+            type="button"
+            onClick={() => setShowManualForm(true)}
+            className="text-xs text-gray-400 hover:text-indigo-600 border border-dashed border-gray-200 hover:border-indigo-300 rounded-lg px-3 py-1.5 transition-colors"
+          >
+            Set metrics manually
+          </button>
+        </div>
+      )}
+      {showManualForm && !status.analysis_summary && (
+        <ManualMetricsForm
+          statusId={status.id}
+          existing={null}
+          onSaved={(summary) => {
+            setStatus((prev) => ({ ...prev, analysis_summary: { ...summary, computed_at: new Date().toISOString() } }));
+            setShowManualForm(false);
+          }}
+          onClose={() => setShowManualForm(false)}
+        />
+      )}
+
+      {/* Past analyses — inline viewer */}
+      <PastAnalysesViewer
+        analyses={analyses}
+        onDelete={(deletedId) => setAnalyses((prev) => prev.filter((x) => x.id !== deletedId))}
+      />
+
+      {/* CSV Analysis — after past analyses */}
+      <CsvAnalysis
+        dailyStatusId={status.id}
+        animal={status.animal}
+        onSaved={(saved) => setAnalyses((prev) => [saved, ...prev])}
+        onSummaryPushed={(summary) => setStatus((prev) => ({ ...prev, analysis_summary: { ...summary, computed_at: new Date().toISOString() } }))}
+      />
+
+      {/* Session file registry */}
+      <FileDropZone
+        rows={[{ animal, status }]}
+        date={String(status.date).slice(0, 10)}
+      />
+
+      {/* Full modification history for this entry */}
+      <AuditLogSection tableName="daily_statuses" recordId={status.id} />
+
+      {/* Prev / Next navigation */}
+      <div className="flex justify-between items-center mt-8 mb-6">
+        <div>
+          {prevStatus && (
+            <button type="button" onClick={() => navigate(`/daily-statuses/${prevStatus.id}`)}
+              className="text-sm text-blue-600 hover:text-blue-800 hover:underline">
+              ← {fmtDate(prevStatus.date)}
+            </button>
+          )}
+        </div>
+        <Link to={`/animals/${animal.id}`} className="text-sm text-gray-500 hover:text-gray-800">
+          All entries
+        </Link>
+        <div>
+          {nextStatus && (
+            <button type="button" onClick={() => navigate(`/daily-statuses/${nextStatus.id}`)}
+              className="text-sm text-blue-600 hover:text-blue-800 hover:underline">
+              {fmtDate(nextStatus.date)} →
+            </button>
+          )}
+        </div>
+      </div>
+
+      {/* Edit modal */}
+      <Modal isOpen={showEdit} onClose={() => setShowEdit(false)} title="Edit Daily Status" size="full">
+        <DailyStatusForm
+          existing={status}
+          animalId={animal.id}
+          experimentId={animal.experiment_id}
+          template={template}
+          onTemplateUpdate={setTemplate}
+          onSuccess={(updated) => { setStatus({ ...updated, animal }); setShowEdit(false); }}
+          onCancel={() => setShowEdit(false)}
+          onRequestDelete={() => { setShowEdit(false); setShowDelete(true); }}
+        />
+      </Modal>
+
+      <ConfirmDialog
+        isOpen={showDelete}
+        onClose={() => setShowDelete(false)}
+        onConfirm={handleDelete}
+        loading={deleteLoading}
+        title="Delete Daily Status"
+        message={`Delete the entry for ${fmtDate(status.date)}? This cannot be undone.`}
+        confirmWord="delete"
+      />
+    </div>
+  );
+}

frontend/src/pages/Dashboard.jsx

@@ -83,7 +83,7 @@ export default function Dashboard() {
       {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
 
       {loading && (
-        <div className="text-center py-16 text-gray-400">Loading experiments…</div>
+        <div className="text-center py-16 text-gray-400" aria-live="polite" aria-busy="true">Loading experiments…</div>
       )}
 
       {!loading && experiments.length === 0 && (

frontend/src/pages/ExperimentDayView.jsx

@@ -0,0 +1,397 @@
+import React, { useEffect, useMemo, useRef, useState } from 'react';
+import { useParams, useNavigate, useSearchParams, Link } from 'react-router-dom';
+import { format } from 'date-fns';
+import {
+  ResponsiveContainer, BarChart, Bar, XAxis, YAxis,
+  CartesianGrid, Tooltip, Legend,
+} from 'recharts';
+import { experimentsApi, dailyStatusesApi } from '../api/client';
+import Button from '../components/ui/Button';
+import Modal from '../components/ui/Modal';
+import DailyStatusForm from '../components/DailyStatusForm';
+import Alert from '../components/ui/Alert';
+import FileDropZone from '../components/FileDropZone';
+
+const BUILTIN_KEYS_SET = new Set(['experiment_description', 'vitals', 'treatment', 'notes']);
+
+function getFieldValue(status, field) {
+  if (field.builtin) return status[field.key];
+  return status.custom_fields?.[field.fieldId];
+}
+
+function cellText(value) {
+  if (value === null || value === undefined || String(value).trim() === '') return null;
+  return String(value);
+}
+
+// ── Inline cell editor ────────────────────────────────────────────────────────
+
+function CellEdit({ value, field, saving, onSave, onCancel }) {
+  const [val, setVal] = useState(value ?? '');
+  const ref = useRef(null);
+
+  useEffect(() => {
+    ref.current?.focus();
+    ref.current?.select();
+  }, []);
+
+  function handleKey(e) {
+    if (e.key === 'Escape') { e.preventDefault(); onCancel(); }
+    if (e.key === 'Enter' && field.type !== 'textarea') { e.preventDefault(); onSave(val); }
+  }
+
+  const cls = 'w-full text-sm border border-blue-400 rounded px-1.5 py-0.5 focus:outline-none focus:ring-2 focus:ring-blue-500 bg-white disabled:opacity-60';
+
+  if (field.type === 'textarea') {
+    return (
+      <textarea
+        ref={ref} value={val} rows={3} disabled={saving}
+        onChange={(e) => setVal(e.target.value)}
+        onBlur={() => onSave(val)}
+        onKeyDown={handleKey}
+        className={cls}
+      />
+    );
+  }
+  return (
+    <input
+      ref={ref} type="text" value={val} disabled={saving}
+      onChange={(e) => setVal(e.target.value)}
+      onBlur={() => onSave(val)}
+      onKeyDown={handleKey}
+      className={cls}
+    />
+  );
+}
+
+// ── Page ──────────────────────────────────────────────────────────────────────
+
+export default function ExperimentDayView() {
+  const { id, date } = useParams();
+  const [searchParams] = useSearchParams();
+  const navigate = useNavigate();
+
+  const [experiment, setExperiment] = useState(null);
+  const [statuses, setStatuses] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [editStatus, setEditStatus] = useState(null);
+
+  // Inline cell editing
+  const [editingCell, setEditingCell] = useState(null); // { statusId, fieldId }
+  const [cellSaving, setCellSaving] = useState(false);
+  const [cellError, setCellError] = useState(null);
+
+  // Day navigation
+  const [dayList, setDayList] = useState([]);
+
+  const selectedField = searchParams.get('field') ?? null;
+
+  useEffect(() => {
+    setLoading(true);
+    Promise.all([
+      experimentsApi.get(id),
+      experimentsApi.getDayStatuses(id, date),
+    ])
+      .then(([exp, s]) => {
+        setExperiment(exp);
+        setStatuses(s);
+      })
+      .catch((err) => setError(err.message ?? 'Failed to load'))
+      .finally(() => setLoading(false));
+  }, [id, date]);
+
+  // Fetch ordered list of days with data for this field, for prev/next nav
+  useEffect(() => {
+    if (!id || !selectedField) return;
+    experimentsApi.getCalendar(id, selectedField)
+      .then(({ days }) => setDayList(Object.keys(days).sort()))
+      .catch(() => {});
+  }, [id, selectedField]);
+
+  const dailyTemplate = useMemo(() => {
+    if (!experiment) return [];
+    return (experiment.template ?? []).filter((f) => f.active);
+  }, [experiment]);
+
+  const animals = useMemo(() => experiment?.animals ?? [], [experiment]);
+
+  const statusByAnimal = useMemo(() => {
+    const map = {};
+    statuses.forEach((s) => { map[s.animal_id] = s; });
+    return map;
+  }, [statuses]);
+
+  const rows = useMemo(() => {
+    return animals
+      .map((animal) => ({ animal, status: statusByAnimal[animal.id] }))
+      .filter(({ status }) => {
+        if (!status) return false;
+        if (!selectedField) return true;
+        const isBuiltin = BUILTIN_KEYS_SET.has(selectedField);
+        const val = isBuiltin ? status[selectedField] : status.custom_fields?.[selectedField];
+        return val !== null && val !== undefined && String(val).trim() !== '';
+      });
+  }, [animals, statusByAnimal, selectedField]);
+
+  const barData = useMemo(() => {
+    return rows
+      .map(({ animal, status }) => {
+        const summary = status?.analysis_summary;
+        if (!summary || summary.total === 0) return null;
+        return {
+          name: animal.animal_name || animal.animal_id_string || animal.id.slice(0, 8),
+          total: summary.total,
+          success: summary.counts?.Success ?? 0,
+          failure: summary.counts?.Failure ?? 0,
+        };
+      })
+      .filter(Boolean);
+  }, [rows]);
+
+  // Prev / next days with data
+  const currentDayIdx = dayList.indexOf(date);
+  const prevDay = currentDayIdx > 0 ? dayList[currentDayIdx - 1] : null;
+  const nextDay = currentDayIdx < dayList.length - 1 ? dayList[currentDayIdx + 1] : null;
+
+  function dayNavUrl(d) {
+    return `/experiments/${id}/day/${d}${selectedField ? `?field=${selectedField}` : ''}`;
+  }
+
+  // Inline cell save
+  async function saveCell(status, field, rawValue) {
+    const value = rawValue?.trim() || null;
+    // Skip save if unchanged
+    const current = getFieldValue(status, field);
+    const currentNorm = current == null ? null : String(current).trim() || null;
+    if (value === currentNorm) { setEditingCell(null); return; }
+
+    setCellSaving(true);
+    setCellError(null);
+    try {
+      let payload;
+      if (field.builtin) {
+        payload = { [field.key]: value };
+      } else {
+        payload = { custom_fields: { ...status.custom_fields, [field.fieldId]: value } };
+      }
+      const updated = await dailyStatusesApi.update(status.id, payload);
+      setStatuses((prev) => prev.map((s) => s.id === updated.id ? updated : s));
+      setEditingCell(null);
+    } catch (err) {
+      setCellError(err.message ?? 'Save failed');
+    } finally {
+      setCellSaving(false);
+    }
+  }
+
+  const displayDate = date
+    ? format(new Date(date + 'T12:00:00'), 'MMMM d, yyyy')
+    : date;
+
+  if (loading) {
+    return <div className="max-w-5xl mx-auto px-4 py-10 text-center text-gray-400">Loading…</div>;
+  }
+  if (error) {
+    return (
+      <div className="max-w-5xl mx-auto px-4 py-10">
+        <Alert type="error" message={error} />
+      </div>
+    );
+  }
+
+  return (
+    <div className="max-w-6xl mx-auto px-4 py-6">
+      {/* Breadcrumb */}
+      <nav className="text-sm text-gray-400 mb-4 flex items-center gap-1.5">
+        <Link to="/" className="hover:text-blue-600 transition-colors">Dashboard</Link>
+        <span>/</span>
+        <Link to={`/experiments/${id}`} className="hover:text-blue-600 transition-colors">
+          {experiment?.title ?? id}
+        </Link>
+        <span>/</span>
+        <span className="text-gray-700 font-medium">{displayDate}</span>
+      </nav>
+
+      <div className="flex items-center justify-between mb-6">
+        <h1 className="text-xl font-bold text-gray-900">{displayDate}</h1>
+        <Button variant="secondary" onClick={() => navigate(`/experiments/${id}`)}>
+          ← Back to experiment
+        </Button>
+      </div>
+
+      {cellError && (
+        <Alert type="error" message={cellError} onDismiss={() => setCellError(null)} className="mb-4" />
+      )}
+
+      {/* Status table */}
+      {rows.length === 0 ? (
+        <div className="text-center py-16 border-2 border-dashed border-gray-200 rounded-xl text-gray-400">
+          No data recorded for this day.
+        </div>
+      ) : (
+        <div className="bg-white rounded-xl border border-gray-200 shadow-sm overflow-hidden mb-8">
+          <div className="overflow-x-auto">
+            <table className="text-sm border-collapse min-w-full">
+              <thead>
+                <tr className="bg-gray-50 border-b border-gray-200">
+                  <th className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide whitespace-nowrap sticky left-0 bg-gray-50 z-10 border-r border-gray-200 min-w-[140px]">
+                    Subject
+                  </th>
+                  {dailyTemplate.map((f) => {
+                    const header = f.abbr
+                      ? (f.unit ? `${f.abbr} (${f.unit})` : f.abbr)
+                      : (f.unit ? `${f.label} (${f.unit})` : f.label);
+                    return (
+                      <th
+                        key={f.fieldId}
+                        title={f.unit ? `${f.label} (${f.unit})` : f.label}
+                        className="text-left px-3 py-2 text-xs font-semibold text-gray-500 uppercase tracking-wide whitespace-nowrap max-w-[220px]"
+                        style={{ minWidth: Math.max(80, header.length * 7.5 + 24) }}
+                      >
+                        {header}
+                      </th>
+                    );
+                  })}
+                  <th className="sticky right-0 bg-gray-50 z-10 border-l border-gray-200 px-3 py-2 min-w-[80px]" />
+                </tr>
+              </thead>
+              <tbody>
+                {rows.map(({ animal, status }, i) => {
+                  const rowBg = i % 2 === 0 ? 'bg-white' : 'bg-gray-50/40';
+                  return (
+                    <tr key={animal.id} className={`border-b border-gray-100 last:border-0 ${rowBg}`}>
+                      {/* Subject name → daily status detail */}
+                      <td
+                        className={`px-3 py-2 font-medium whitespace-nowrap sticky left-0 z-10 border-r border-gray-100 ${rowBg} ${
+                          status
+                            ? 'text-blue-600 cursor-pointer hover:text-blue-800 hover:bg-blue-50/40 transition-colors'
+                            : 'text-gray-500'
+                        }`}
+                        onClick={() => status && navigate(`/daily-statuses/${status.id}`)}
+                      >
+                        {animal.animal_name ?? animal.animal_id_string ?? animal.id.slice(0, 8)}
+                        {animal.animal_id_string && animal.animal_name && (
+                          <span className="ml-1.5 text-xs text-gray-400 font-normal">
+                            {animal.animal_id_string}
+                          </span>
+                        )}
+                      </td>
+
+                      {/* Field cells — click to edit inline */}
+                      {dailyTemplate.map((f) => {
+                        const isEditing = editingCell?.statusId === status?.id && editingCell?.fieldId === f.fieldId;
+                        const text = status ? cellText(getFieldValue(status, f)) : null;
+                        return (
+                          <td key={f.fieldId} className="px-3 py-1.5 text-gray-700 max-w-[220px] align-top">
+                            {isEditing ? (
+                              <CellEdit
+                                value={text}
+                                field={f}
+                                saving={cellSaving}
+                                onSave={(val) => saveCell(status, f, val)}
+                                onCancel={() => setEditingCell(null)}
+                              />
+                            ) : (
+                              <span
+                                className="whitespace-pre-wrap break-words block rounded px-0.5 -mx-0.5 cursor-pointer hover:bg-blue-50 transition-colors"
+                                title="Click to edit"
+                                onClick={() => status && setEditingCell({ statusId: status.id, fieldId: f.fieldId })}
+                              >
+                                {text ?? <span className="text-gray-300">—</span>}
+                              </span>
+                            )}
+                          </td>
+                        );
+                      })}
+
+                      <td className={`px-2 py-1.5 sticky right-0 z-10 border-l border-gray-100 ${rowBg}`}>
+                        {status && (
+                          <Button size="sm" variant="secondary" onClick={() => setEditStatus(status)}>
+                            Edit
+                          </Button>
+                        )}
+                      </td>
+                    </tr>
+                  );
+                })}
+              </tbody>
+            </table>
+          </div>
+        </div>
+      )}
+
+      {/* Session metrics bar chart */}
+      {barData.length > 0 && (
+        <div className="bg-white rounded-xl border border-gray-200 shadow-sm p-5 mb-8">
+          <h3 className="text-sm font-semibold text-gray-700 mb-3">Session metrics</h3>
+          <ResponsiveContainer width="100%" height={220}>
+            <BarChart data={barData} margin={{ top: 4, right: 16, left: 0, bottom: 4 }}>
+              <CartesianGrid strokeDasharray="3 3" stroke="#f0f0f0" />
+              <XAxis dataKey="name" tick={{ fontSize: 11 }} />
+              <YAxis tick={{ fontSize: 11 }} allowDecimals={false} />
+              <Tooltip />
+              <Legend wrapperStyle={{ fontSize: 11 }} />
+              <Bar dataKey="total" name="Total" fill="#94a3b8" radius={[3, 3, 0, 0]} />
+              <Bar dataKey="success" name="Success" fill="#22c55e" radius={[3, 3, 0, 0]} />
+              <Bar dataKey="failure" name="Failure" fill="#f87171" radius={[3, 3, 0, 0]} minPointSize={2} />
+            </BarChart>
+          </ResponsiveContainer>
+        </div>
+      )}
+
+      {/* Prev / next day navigation */}
+      {(prevDay || nextDay) && (
+        <div className="flex justify-between items-center mt-2 mb-4">
+          <div>
+            {prevDay && (
+              <button
+                type="button"
+                onClick={() => navigate(dayNavUrl(prevDay))}
+                className="text-sm text-blue-600 hover:text-blue-800 hover:underline"
+              >
+                ← {format(new Date(prevDay + 'T12:00:00'), 'MMMM d, yyyy')}
+              </button>
+            )}
+          </div>
+          <div>
+            {nextDay && (
+              <button
+                type="button"
+                onClick={() => navigate(dayNavUrl(nextDay))}
+                className="text-sm text-blue-600 hover:text-blue-800 hover:underline"
+              >
+                {format(new Date(nextDay + 'T12:00:00'), 'MMMM d, yyyy')} →
+              </button>
+            )}
+          </div>
+        </div>
+      )}
+
+      {/* Session file drop zone */}
+      <FileDropZone rows={rows} date={date} />
+
+      {/* Edit modal (full row) */}
+      {editStatus && (
+        <Modal
+          isOpen={!!editStatus}
+          onClose={() => setEditStatus(null)}
+          title="Edit daily status"
+          size="lg"
+        >
+          <DailyStatusForm
+            existing={editStatus}
+            animalId={editStatus.animal_id}
+            experimentId={id}
+            template={dailyTemplate}
+            onSuccess={(updated) => {
+              setStatuses((prev) => prev.map((s) => s.id === updated.id ? updated : s));
+              setEditStatus(null);
+            }}
+            onCancel={() => setEditStatus(null)}
+          />
+        </Modal>
+      )}
+    </div>
+  );
+}

frontend/src/pages/ExperimentDetail.jsx

@@ -1,12 +1,53 @@
-import React, { useEffect, useState } from 'react';
+import React, { useEffect, useState, useMemo } from 'react';
 import { useParams, useNavigate, Link } from 'react-router-dom';
 import { experimentsApi, animalsApi } from '../api/client';
+import { ExperimentAnalysisCharts } from '../components/AnalysisCharts';
 import Button from '../components/ui/Button';
 import Modal from '../components/ui/Modal';
-import ConfirmDialog from '../components/ui/ConfirmDialog';
 import AnimalForm from '../components/AnimalForm';
+import TemplateEditor from '../components/TemplateEditor';
 import Alert from '../components/ui/Alert';
 import AuditLogSection from '../components/AuditLogSection';
+import ExperimentCalendar from '../components/ExperimentCalendar';
+import ExportDataModal from '../components/ExportDataModal';
+
+function AnimalCardList({ animals, subjectTemplate, onNavigate, onEdit }) {
+  return (
+    <div className="grid gap-3">
+      {animals.map((animal) => {
+        const infoFields = subjectTemplate.filter((f) => f.active && animal.subject_info?.[f.fieldId] != null);
+        return (
+          <div
+            key={animal.id}
+            className="bg-white border border-gray-200 rounded-xl p-4 flex items-center justify-between hover:border-blue-300 hover:shadow-sm transition-all cursor-pointer group"
+            onClick={() => onNavigate(animal)}
+          >
+            <div>
+              <div className="font-semibold text-gray-900 group-hover:text-blue-700 transition-colors">
+                {animal.animal_name}
+              </div>
+              <div className="text-sm text-gray-500">
+                ID: {animal.animal_id_string} · {animal._count?.daily_statuses ?? 0} daily status entries
+              </div>
+              {infoFields.length > 0 && (
+                <div className="flex flex-wrap gap-x-3 gap-y-0.5 mt-1">
+                  {infoFields.map((f) => (
+                    <span key={f.fieldId} className="text-xs text-gray-400">
+                      <span className="font-medium text-gray-500">{f.label}:</span> {animal.subject_info[f.fieldId]}
+                    </span>
+                  ))}
+                </div>
+              )}
+            </div>
+            <div className="flex gap-2" onClick={(e) => e.stopPropagation()}>
+              <Button size="sm" variant="secondary" onClick={() => onEdit(animal)}>Edit</Button>
+            </div>
+          </div>
+        );
+      })}
+    </div>
+  );
+}
 
 export default function ExperimentDetail() {
   const { id } = useParams();
@@ -20,19 +61,51 @@ export default function ExperimentDetail() {
 
   const [showAddAnimal, setShowAddAnimal] = useState(false);
   const [editAnimal, setEditAnimal] = useState(null);
-  const [deleteAnimal, setDeleteAnimal] = useState(null);
-  const [deleteLoading, setDeleteLoading] = useState(false);
+  const [showTemplate, setShowTemplate] = useState(false);
+  const [showSubjectTemplate, setShowSubjectTemplate] = useState(false);
+  const [showExport, setShowExport] = useState(false);
+  const [subjectTemplate, setSubjectTemplate] = useState([]);
+  const [dailyTemplate, setDailyTemplate] = useState([]);
+  const [experimentStatuses, setExperimentStatuses] = useState([]);
+
+  const [displayMode, setDisplayMode] = useState(() => localStorage.getItem(`exp-display-mode-${id}`) ?? 'list');
+  const [sortField,   setSortField]   = useState(() => localStorage.getItem(`exp-subject-sort-${id}`) ?? '__name__');
+  const [sortDir,     setSortDir]     = useState(() => localStorage.getItem(`exp-subject-sort-dir-${id}`) ?? 'asc');
+  const [groupField,  setGroupField]  = useState(() => localStorage.getItem(`exp-subject-group-${id}`) ?? '__name__');
+
+  function updateDisplayMode(mode) {
+    setDisplayMode(mode);
+    localStorage.setItem(`exp-display-mode-${id}`, mode);
+  }
+  function updateSort(field, dir) {
+    setSortField(field);
+    setSortDir(dir);
+    localStorage.setItem(`exp-subject-sort-${id}`, field);
+    localStorage.setItem(`exp-subject-sort-dir-${id}`, dir);
+  }
+  function updateGroupField(field) {
+    setGroupField(field);
+    localStorage.setItem(`exp-subject-group-${id}`, field);
+  }
 
   async function load() {
     setLoading(true);
     setError(null);
     try {
-      const [exp, anims] = await Promise.all([
+      const [exp, anims, subjTmpl, dailyTmpl, expStatuses] = await Promise.all([
         experimentsApi.get(id),
         animalsApi.list(id),
+        experimentsApi.getSubjectTemplate(id),
+        experimentsApi.getTemplate(id),
+        // Only fetch statuses that have saved analysis_summary — charts are the only consumer,
+        // and they filter for analysis_summary.total != null anyway.
+        experimentsApi.getDailyStatuses(id, { analysisOnly: true }),
       ]);
       setExperiment(exp);
       setAnimals(anims);
+      setSubjectTemplate(subjTmpl);
+      setDailyTemplate(dailyTmpl);
+      setExperimentStatuses(expStatuses);
     } catch (err) {
       setError(err.message);
     } finally {
@@ -54,22 +127,59 @@ export default function ExperimentDetail() {
     flash(editAnimal ? `Animal "${animal.animal_name}" updated.` : `Animal "${animal.animal_name}" added.`);
   }
 
-  async function handleDeleteAnimal() {
-    setDeleteLoading(true);
-    try {
-      await animalsApi.delete(deleteAnimal.id);
-      setDeleteAnimal(null);
-      load();
-      flash('Animal removed.');
-    } catch (err) {
-      setError(err.message);
-      setDeleteAnimal(null);
-    } finally {
-      setDeleteLoading(false);
+  function handleTemplateSaved(updatedTemplate) {
+    setShowTemplate(false);
+    if (updatedTemplate) {
+      // Update local experiment state so everything downstream re-renders
+      setExperiment((prev) => ({ ...prev, template: updatedTemplate }));
+      flash('Record template updated.');
     }
   }
 
-  if (loading) return <div className="max-w-5xl mx-auto px-4 py-8 text-gray-400">Loading…</div>;
+  const sortedAnimals = useMemo(() => {
+    const sorted = [...animals].sort((a, b) => {
+      let av, bv;
+      if (sortField === '__name__') {
+        av = a.animal_name ?? '';
+        bv = b.animal_name ?? '';
+      } else if (sortField === '__id__') {
+        av = a.animal_id_string ?? '';
+        bv = b.animal_id_string ?? '';
+      } else {
+        av = a.subject_info?.[sortField] ?? '';
+        bv = b.subject_info?.[sortField] ?? '';
+      }
+      // numeric-aware comparison
+      const an = parseFloat(av), bn = parseFloat(bv);
+      const cmp = (!isNaN(an) && !isNaN(bn)) ? an - bn : String(av).localeCompare(String(bv));
+      return sortDir === 'asc' ? cmp : -cmp;
+    });
+    return sorted;
+  }, [animals, sortField, sortDir, subjectTemplate]);
+
+  // Group mode: bucket sortedAnimals by the groupField value
+  const groupedAnimals = useMemo(() => {
+    if (displayMode !== 'group') return null;
+    const getVal = (animal) => {
+      if (groupField === '__name__') return animal.animal_name ?? '—';
+      if (groupField === '__id__')   return animal.animal_id_string ?? '—';
+      const v = animal.subject_info?.[groupField];
+      return v != null && v !== '' ? String(v) : '—';
+    };
+    const buckets = new Map();
+    for (const animal of sortedAnimals) {
+      const key = getVal(animal);
+      if (!buckets.has(key)) buckets.set(key, []);
+      buckets.get(key).push(animal);
+    }
+    // Sort bucket keys numerically-aware
+    return [...buckets.entries()].sort(([a], [b]) => {
+      const an = parseFloat(a), bn = parseFloat(b);
+      return (!isNaN(an) && !isNaN(bn)) ? an - bn : a.localeCompare(b);
+    });
+  }, [sortedAnimals, displayMode, groupField]);
+
+  if (loading) return <div className="max-w-5xl mx-auto px-4 py-8 text-gray-400" aria-live="polite" aria-busy="true">Loading…</div>;
   if (error) return (
     <div className="max-w-5xl mx-auto px-4 py-8">
       <Alert type="error" message={error} />
@@ -93,65 +203,225 @@ export default function ExperimentDetail() {
             {animals.length} animal{animals.length !== 1 ? 's' : ''} enrolled
           </p>
         </div>
-        <Button onClick={() => setShowAddAnimal(true)}>+ Add Animal</Button>
+        <div className="flex gap-2">
+          <Button variant="secondary" onClick={() => setShowExport(true)}>Export data</Button>
+          <Button onClick={() => setShowAddAnimal(true)}>+ Add Animal</Button>
+        </div>
       </div>
 
       {successMsg && <Alert type="success" message={successMsg} />}
       {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
 
+      {/* Template strips */}
+      <div className="mb-5 space-y-2">
+        {/* Daily record template */}
+        <div className="flex flex-wrap items-center gap-1.5">
+          <span className="text-xs font-semibold text-gray-400 uppercase tracking-wide w-24 shrink-0">Daily record</span>
+          {(experiment.template ?? []).map((f) => (
+            <span
+              key={f.key}
+              className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-medium border ${
+                f.active ? 'bg-blue-50 border-blue-200 text-blue-700' : 'bg-gray-100 border-gray-200 text-gray-400'
+              }`}
+            >
+              {f.active ? null : <span title="hidden">◌</span>}
+              {f.label}
+            </span>
+          ))}
+          <button
+            onClick={() => setShowTemplate(true)}
+            className="inline-flex items-center gap-1 text-xs text-gray-400 hover:text-blue-600 transition-colors"
+          >
+            <svg className="w-3.5 h-3.5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15.232 5.232l3.536 3.536M9 13l6.586-6.586a2 2 0 112.828 2.828L11.828 15.828A2 2 0 0110 16.414V19h2.586a2 2 0 001.414-.586l6.5-6.5" />
+            </svg>
+            {(experiment.template ?? []).length === 0 ? 'Set up' : 'Edit'}
+          </button>
+        </div>
+
+        {/* Subject info template */}
+        <div className="flex flex-wrap items-center gap-1.5">
+          <span className="text-xs font-semibold text-gray-400 uppercase tracking-wide w-24 shrink-0">Subject info</span>
+          {subjectTemplate.map((f) => (
+            <span
+              key={f.key}
+              className={`inline-flex items-center gap-1 px-2 py-0.5 rounded-full text-xs font-medium border ${
+                f.active ? 'bg-emerald-50 border-emerald-200 text-emerald-700' : 'bg-gray-100 border-gray-200 text-gray-400'
+              }`}
+            >
+              {f.active ? null : <span title="hidden">◌</span>}
+              {f.label}
+            </span>
+          ))}
+          <button
+            onClick={() => setShowSubjectTemplate(true)}
+            className="inline-flex items-center gap-1 text-xs text-gray-400 hover:text-emerald-600 transition-colors"
+          >
+            <svg className="w-3.5 h-3.5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M15.232 5.232l3.536 3.536M9 13l6.586-6.586a2 2 0 112.828 2.828L11.828 15.828A2 2 0 0110 16.414V19h2.586a2 2 0 001.414-.586l6.5-6.5" />
+            </svg>
+            {subjectTemplate.length === 0 ? 'Set up' : 'Edit'}
+          </button>
+        </div>
+      </div>
+
       {animals.length === 0 ? (
         <div className="text-center py-16 border-2 border-dashed border-gray-200 rounded-xl">
           <p className="text-gray-400 mb-3">No animals enrolled in this experiment yet.</p>
           <Button onClick={() => setShowAddAnimal(true)}>+ Add First Animal</Button>
         </div>
       ) : (
-        <div className="grid gap-3">
-          {animals.map((animal) => (
-            <div
-              key={animal.id}
-              className="bg-white border border-gray-200 rounded-xl p-4 flex items-center justify-between hover:border-blue-300 hover:shadow-sm transition-all cursor-pointer group"
-              onClick={() => navigate(`/animals/${animal.id}`)}
-            >
-              <div>
-                <div className="font-semibold text-gray-900 group-hover:text-blue-700 transition-colors">
-                  {animal.animal_name}
-                </div>
-                <div className="text-sm text-gray-500">
-                  ID: {animal.animal_id_string} · {animal._count?.daily_statuses ?? 0} daily status entries
-                </div>
-              </div>
-              <div className="flex gap-2" onClick={(e) => e.stopPropagation()}>
-                <Button size="sm" variant="secondary" onClick={() => setEditAnimal(animal)}>Edit</Button>
-                <Button size="sm" variant="danger" onClick={() => setDeleteAnimal(animal)}>Remove</Button>
-              </div>
+        <>
+          {/* Display controls */}
+          <div className="flex items-center gap-3 mb-3 flex-wrap">
+            {/* Mode toggle */}
+            <div className="flex rounded border border-gray-200 overflow-hidden text-xs">
+              {[['list', 'List'], ['group', 'Group']].map(([mode, label]) => (
+                <button key={mode} type="button" onClick={() => updateDisplayMode(mode)}
+                  className={`px-3 py-1 border-l border-gray-200 first:border-l-0 transition-colors
+                    ${displayMode === mode ? 'bg-gray-700 text-white' : 'bg-white text-gray-500 hover:bg-gray-50'}`}>
+                  {label}
+                </button>
+              ))}
             </div>
-          ))}
-        </div>
+
+            {displayMode === 'list' && (
+              <>
+                <span className="text-xs text-gray-400">Sort by</span>
+                <select value={sortField} onChange={(e) => updateSort(e.target.value, sortDir)}
+                  className="border border-gray-200 rounded px-2 py-1 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400">
+                  <option value="__name__">Name</option>
+                  <option value="__id__">Subject ID</option>
+                  {subjectTemplate.filter((f) => f.active).map((f) => (
+                    <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+                  ))}
+                </select>
+                <button type="button" onClick={() => updateSort(sortField, sortDir === 'asc' ? 'desc' : 'asc')}
+                  className="text-xs text-gray-500 hover:text-gray-800 border border-gray-200 rounded px-2 py-1 bg-white transition-colors">
+                  {sortDir === 'asc' ? '↑ Asc' : '↓ Desc'}
+                </button>
+              </>
+            )}
+
+            {displayMode === 'group' && (
+              <>
+                <span className="text-xs text-gray-400">Group by</span>
+                <select value={groupField} onChange={(e) => updateGroupField(e.target.value)}
+                  className="border border-gray-200 rounded px-2 py-1 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400">
+                  <option value="__name__">Name</option>
+                  <option value="__id__">Subject ID</option>
+                  {subjectTemplate.filter((f) => f.active).map((f) => (
+                    <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+                  ))}
+                </select>
+                <span className="text-xs text-gray-400 ml-1">· sorted within by</span>
+                <select value={sortField} onChange={(e) => updateSort(e.target.value, sortDir)}
+                  className="border border-gray-200 rounded px-2 py-1 text-xs bg-white focus:outline-none focus:ring-1 focus:ring-indigo-400">
+                  <option value="__name__">Name</option>
+                  <option value="__id__">Subject ID</option>
+                  {subjectTemplate.filter((f) => f.active).map((f) => (
+                    <option key={f.fieldId} value={f.fieldId}>{f.label}</option>
+                  ))}
+                </select>
+                <button type="button" onClick={() => updateSort(sortField, sortDir === 'asc' ? 'desc' : 'asc')}
+                  className="text-xs text-gray-500 hover:text-gray-800 border border-gray-200 rounded px-2 py-1 bg-white transition-colors">
+                  {sortDir === 'asc' ? '↑ Asc' : '↓ Desc'}
+                </button>
+              </>
+            )}
+          </div>
+
+          {displayMode === 'list' && (
+            <AnimalCardList
+              animals={sortedAnimals}
+              subjectTemplate={subjectTemplate}
+              onNavigate={(animal) => navigate(`/animals/${animal.id}`, { state: { template: experiment.template } })}
+              onEdit={setEditAnimal}
+            />
+          )}
+
+          {displayMode === 'group' && groupedAnimals && groupedAnimals.map(([groupValue, groupAnimals]) => {
+            const groupLabel = (() => {
+              if (groupField === '__name__' || groupField === '__id__') return groupValue;
+              return subjectTemplate.find((f) => f.fieldId === groupField)?.label
+                ? `${subjectTemplate.find((f) => f.fieldId === groupField).label}: ${groupValue}`
+                : groupValue;
+            })();
+            return (
+              <div key={groupValue} className="mb-5">
+                <div className="flex items-center gap-2 mb-2">
+                  <span className="text-xs font-semibold text-gray-500 uppercase tracking-wide">{groupLabel}</span>
+                  <span className="text-xs text-gray-400">({groupAnimals.length})</span>
+                  <div className="flex-1 border-t border-gray-100" />
+                </div>
+                <AnimalCardList
+                  animals={groupAnimals}
+                  subjectTemplate={subjectTemplate}
+                  onNavigate={(animal) => navigate(`/animals/${animal.id}`, { state: { template: experiment.template } })}
+                  onEdit={setEditAnimal}
+                />
+              </div>
+            );
+          })}
+
+        </>
       )}
 
-      <AuditLogSection tableName="animals" recordId={undefined} />
+      <ExperimentAnalysisCharts
+        animals={animals}
+        experimentStatuses={experimentStatuses}
+        subjectTemplate={subjectTemplate}
+        dailyTemplate={dailyTemplate}
+        plotConfig={experiment.plot_config}
+        onPersistConfig={(cfg) => experimentsApi.savePlotConfig(id, cfg)}
+      />
+
+      {animals.length > 0 && (
+        <ExperimentCalendar
+          experimentId={id}
+          template={dailyTemplate}
+        />
+      )}
+
+      <AuditLogSection tableName="animals" limit={5} />
+
+      {/* Template editor modal */}
+      <Modal isOpen={showTemplate} onClose={() => setShowTemplate(false)} title="Daily Record Template" size="full">
+        <TemplateEditor experimentId={id} onClose={handleTemplateSaved} />
+      </Modal>
+
+      <Modal isOpen={showSubjectTemplate} onClose={() => setShowSubjectTemplate(false)} title="Subject Info Template" size="full">
+        <TemplateEditor
+          experimentId={id}
+          loadFn={() => experimentsApi.getSubjectTemplate(id)}
+          saveFn={(fields) => experimentsApi.updateSubjectTemplate(id, fields)}
+          onClose={(updated) => {
+            setShowSubjectTemplate(false);
+            if (updated) { setSubjectTemplate(updated); flash('Subject info template updated.'); }
+          }}
+        />
+      </Modal>
 
       <Modal isOpen={showAddAnimal} onClose={() => setShowAddAnimal(false)} title="Add Animal">
         <AnimalForm experimentId={id} onSuccess={handleAnimalSaved} onCancel={() => setShowAddAnimal(false)} />
       </Modal>
 
       <Modal isOpen={!!editAnimal} onClose={() => setEditAnimal(null)} title="Edit Animal">
-        <AnimalForm
-          existing={editAnimal}
+        <AnimalForm existing={editAnimal} experimentId={id} onSuccess={handleAnimalSaved} onCancel={() => setEditAnimal(null)} />
+      </Modal>
+
+      <Modal isOpen={showExport} onClose={() => setShowExport(false)} title="Export data" size="md">
+        <ExportDataModal
           experimentId={id}
-          onSuccess={handleAnimalSaved}
-          onCancel={() => setEditAnimal(null)}
+          experimentTitle={experiment.title}
+          dailyTemplate={dailyTemplate}
+          animals={animals}
+          subjectTemplate={subjectTemplate}
+          groupField={localStorage.getItem(`exp-subject-group-${id}`) ?? '__none__'}
+          onClose={() => setShowExport(false)}
         />
       </Modal>
 
-      <ConfirmDialog
-        isOpen={!!deleteAnimal}
-        onClose={() => setDeleteAnimal(null)}
-        onConfirm={handleDeleteAnimal}
-        loading={deleteLoading}
-        title="Remove Animal"
-        message={`Remove "${deleteAnimal?.animal_name}" and all its daily statuses from this experiment?`}
-      />
     </div>
   );
 }

frontend/tailwind.config.js

@@ -15,5 +15,6 @@ module.exports = {
       },
     },
   },
+  safelist: ['col-span-1', 'col-span-2', 'col-span-3', 'col-span-4', 'col-span-5', 'col-span-6', 'col-span-8', 'col-span-9', 'col-span-12'],
   plugins: [],
 };

frontend/tests/AnimalForm.test.jsx

@@ -0,0 +1,73 @@
+import React from 'react';
+import { render, screen, fireEvent, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import AnimalForm from '../src/components/AnimalForm';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  animalsApi: {
+    create: jest.fn(),
+    update: jest.fn(),
+  },
+}));
+
+const EXP_ID = 'exp-001';
+const onSuccess = jest.fn();
+const onCancel = jest.fn();
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('AnimalForm', () => {
+  it('renders Animal ID and Animal Name fields', () => {
+    render(<AnimalForm experimentId={EXP_ID} onSuccess={onSuccess} onCancel={onCancel} />);
+    expect(screen.getByLabelText(/animal id/i)).toBeInTheDocument();
+    expect(screen.getByLabelText(/animal name/i)).toBeInTheDocument();
+  });
+
+  it('shows required field errors on empty submit', async () => {
+    render(<AnimalForm experimentId={EXP_ID} onSuccess={onSuccess} onCancel={onCancel} />);
+    fireEvent.click(screen.getByRole('button', { name: /add animal/i }));
+    expect(await screen.findAllByRole('alert')).toHaveLength(2);
+    expect(client.animalsApi.create).not.toHaveBeenCalled();
+  });
+
+  it('calls create with correct payload', async () => {
+    const animal = { id: 'a-1', animal_id_string: 'M-001', animal_name: 'Whiskers', experiment_id: EXP_ID };
+    client.animalsApi.create.mockResolvedValue(animal);
+
+    render(<AnimalForm experimentId={EXP_ID} onSuccess={onSuccess} onCancel={onCancel} />);
+    await userEvent.type(screen.getByLabelText(/animal id/i), 'M-001');
+    await userEvent.type(screen.getByLabelText(/animal name/i), 'Whiskers');
+    fireEvent.click(screen.getByRole('button', { name: /add animal/i }));
+
+    await waitFor(() =>
+      expect(client.animalsApi.create).toHaveBeenCalledWith({
+        animal_id_string: 'M-001',
+        animal_name: 'Whiskers',
+        experiment_id: EXP_ID,
+      })
+    );
+    await waitFor(() => expect(onSuccess).toHaveBeenCalledWith(animal));
+  });
+
+  it('pre-fills fields for existing animal and uses update API', async () => {
+    const existing = { id: 'a-1', animal_id_string: 'M-001', animal_name: 'Whiskers' };
+    const updated = { ...existing, animal_name: 'Mr Whiskers' };
+    client.animalsApi.update.mockResolvedValue(updated);
+
+    render(<AnimalForm existing={existing} experimentId={EXP_ID} onSuccess={onSuccess} onCancel={onCancel} />);
+    expect(screen.getByDisplayValue('Whiskers')).toBeInTheDocument();
+
+    const nameInput = screen.getByLabelText(/animal name/i);
+    await userEvent.clear(nameInput);
+    await userEvent.type(nameInput, 'Mr Whiskers');
+    fireEvent.click(screen.getByRole('button', { name: /save changes/i }));
+
+    await waitFor(() =>
+      expect(client.animalsApi.update).toHaveBeenCalledWith('a-1', {
+        animal_id_string: 'M-001',
+        animal_name: 'Mr Whiskers',
+      })
+    );
+  });
+});

frontend/tests/Button.test.jsx

@@ -0,0 +1,42 @@
+import React from 'react';
+import { render, screen, fireEvent } from '@testing-library/react';
+import Button from '../src/components/ui/Button';
+
+describe('Button component', () => {
+  it('renders with children text', () => {
+    render(<Button>Click me</Button>);
+    expect(screen.getByRole('button', { name: /click me/i })).toBeInTheDocument();
+  });
+
+  it('calls onClick when clicked', () => {
+    const onClick = jest.fn();
+    render(<Button onClick={onClick}>Click</Button>);
+    fireEvent.click(screen.getByRole('button'));
+    expect(onClick).toHaveBeenCalledTimes(1);
+  });
+
+  it('is disabled when disabled prop is true', () => {
+    render(<Button disabled>Submit</Button>);
+    expect(screen.getByRole('button')).toBeDisabled();
+  });
+
+  it('is disabled and shows spinner when loading', () => {
+    render(<Button loading>Submit</Button>);
+    const btn = screen.getByRole('button');
+    expect(btn).toBeDisabled();
+    expect(btn.querySelector('svg')).toBeTruthy();
+  });
+
+  it('renders danger variant', () => {
+    render(<Button variant="danger">Delete</Button>);
+    const btn = screen.getByRole('button');
+    expect(btn.className).toContain('bg-red-600');
+  });
+
+  it('does not call onClick when disabled', () => {
+    const onClick = jest.fn();
+    render(<Button disabled onClick={onClick}>Click</Button>);
+    fireEvent.click(screen.getByRole('button'));
+    expect(onClick).not.toHaveBeenCalled();
+  });
+});

frontend/tests/DailyStatusForm.test.jsx

@@ -0,0 +1,103 @@
+import React from 'react';
+import { render, screen, fireEvent, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import DailyStatusForm from '../src/components/DailyStatusForm';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  dailyStatusesApi: {
+    create: jest.fn(),
+    update: jest.fn(),
+  },
+  experimentsApi: {
+    updateTemplate: jest.fn(),
+  },
+}));
+
+const ANIMAL_ID = 'animal-001';
+const onSuccess = jest.fn();
+const onCancel = jest.fn();
+
+const BUILTIN_TEMPLATE = [
+  { fieldId: 'f1', key: 'vitals', label: 'Vitals', type: 'textarea', builtin: true, active: true, width: 100 },
+  { fieldId: 'f2', key: 'treatment', label: 'Treatment', type: 'textarea', builtin: true, active: true, width: 100 },
+  { fieldId: 'f3', key: 'notes', label: 'Notes', type: 'textarea', builtin: true, active: true, width: 100 },
+  { fieldId: 'f4', key: 'experiment_description', label: 'Experiment Description', type: 'textarea', builtin: true, active: true, width: 100 },
+];
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('DailyStatusForm', () => {
+  it('renders date field (required) and optional fields', () => {
+    render(<DailyStatusForm animalId={ANIMAL_ID} template={BUILTIN_TEMPLATE} onSuccess={onSuccess} onCancel={onCancel} />);
+    expect(screen.getByLabelText(/date/i)).toBeInTheDocument();
+    expect(screen.getByLabelText(/vitals/i)).toBeInTheDocument();
+    expect(screen.getByLabelText(/treatment/i)).toBeInTheDocument();
+    expect(screen.getByLabelText(/notes/i)).toBeInTheDocument();
+    expect(screen.getByLabelText(/experiment description/i)).toBeInTheDocument();
+  });
+
+  it('pre-fills date with today by default', () => {
+    render(<DailyStatusForm animalId={ANIMAL_ID} template={BUILTIN_TEMPLATE} onSuccess={onSuccess} onCancel={onCancel} />);
+    const today = new Date().toISOString().slice(0, 10);
+    expect(screen.getByLabelText(/date/i)).toHaveValue(today);
+  });
+
+  it('shows error when date is cleared', async () => {
+    render(<DailyStatusForm animalId={ANIMAL_ID} template={BUILTIN_TEMPLATE} onSuccess={onSuccess} onCancel={onCancel} />);
+    const dateInput = screen.getByLabelText(/date/i);
+    await userEvent.clear(dateInput);
+    fireEvent.click(screen.getByRole('button', { name: /log status/i }));
+    expect(await screen.findByRole('alert')).toHaveTextContent(/date is required/i);
+    expect(client.dailyStatusesApi.create).not.toHaveBeenCalled();
+  });
+
+  it('calls create with correct payload including animal_id', async () => {
+    const status = { id: 's-1', animal_id: ANIMAL_ID, date: '2024-06-01', vitals: 'HR 72' };
+    client.dailyStatusesApi.create.mockResolvedValue(status);
+
+    render(<DailyStatusForm animalId={ANIMAL_ID} template={BUILTIN_TEMPLATE} onSuccess={onSuccess} onCancel={onCancel} />);
+
+    const dateInput = screen.getByLabelText(/date/i);
+    fireEvent.change(dateInput, { target: { value: '2024-06-01' } });
+
+    await userEvent.type(screen.getByLabelText(/vitals/i), 'HR 72');
+
+    fireEvent.click(screen.getByRole('button', { name: /log status/i }));
+
+    await waitFor(() =>
+      expect(client.dailyStatusesApi.create).toHaveBeenCalledWith(
+        expect.objectContaining({ animal_id: ANIMAL_ID, vitals: 'HR 72' })
+      )
+    );
+    await waitFor(() => expect(onSuccess).toHaveBeenCalled());
+  });
+
+  it('shows "Save Changes" and pre-fills fields for existing status', () => {
+    const existing = {
+      id: 's-1',
+      date: '2024-06-01T00:00:00.000Z',
+      vitals: 'HR 72',
+      treatment: 'Control',
+      notes: 'Normal',
+      experiment_description: 'Baseline',
+    };
+    render(
+      <DailyStatusForm
+        existing={existing}
+        template={BUILTIN_TEMPLATE}
+        animalId={ANIMAL_ID}
+        onSuccess={onSuccess}
+        onCancel={onCancel}
+      />
+    );
+    expect(screen.getByRole('button', { name: /save changes/i })).toBeInTheDocument();
+    expect(screen.getByDisplayValue('HR 72')).toBeInTheDocument();
+  });
+
+  it('calls onCancel when Cancel is clicked', () => {
+    render(<DailyStatusForm animalId={ANIMAL_ID} template={BUILTIN_TEMPLATE} onSuccess={onSuccess} onCancel={onCancel} />);
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    expect(onCancel).toHaveBeenCalled();
+  });
+});

frontend/tests/ExperimentAnalysisCharts.test.jsx

@@ -0,0 +1,126 @@
+import React from 'react';
+import { render, screen, fireEvent, act } from '@testing-library/react';
+
+// recharts uses ResizeObserver (absent in jsdom); stub all used pieces as passthroughs.
+// Coverage boundary: with recharts mocked out, these tests cover only the sidebar
+// integration path (toggle, checkbox state, persistence). The legend onClick/hover
+// wiring, line hide/strokeWidth, and tooltip ordering are exercised by the pure-helper
+// unit tests (crossSubjectChart.test.js) and SubjectSidebar.test.jsx.
+jest.mock('recharts', () => {
+  const Pass = ({ children }) => <div>{children}</div>;
+  return {
+    ResponsiveContainer: Pass, LineChart: Pass, Line: () => null,
+    XAxis: () => null, YAxis: () => null, CartesianGrid: () => null,
+    Tooltip: () => null, Legend: () => null,
+  };
+});
+
+import { ExperimentAnalysisCharts } from '../src/components/AnalysisCharts';
+
+const ANIMALS = [
+  { id: 'a1', animal_name: 'Mouse-A1', subject_info: { grp: 'Group A' } },
+  { id: 'b1', animal_name: 'Mouse-B1', subject_info: { grp: 'Group B' } },
+];
+const STATUSES = [
+  { animal_id: 'a1', date: '2026-01-01', analysis_summary: { total: 10, success_rate: 0.5, counts: { Success: 5 } } },
+  { animal_id: 'b1', date: '2026-01-01', analysis_summary: { total: 8, success_rate: 0.25, counts: { Success: 2 } } },
+];
+const SUBJECT_TEMPLATE = [{ fieldId: 'grp', label: 'Group', active: true }];
+const DAILY_TEMPLATE = [];
+
+function renderChart() {
+  render(
+    <ExperimentAnalysisCharts
+      animals={ANIMALS}
+      experimentStatuses={STATUSES}
+      subjectTemplate={SUBJECT_TEMPLATE}
+      dailyTemplate={DAILY_TEMPLATE}
+    />,
+  );
+}
+
+it('toggles the subject sidebar open and closed', () => {
+  renderChart();
+  expect(screen.queryByText('Subjects')).toBeNull();
+  fireEvent.click(screen.getByText('▸ Subjects'));
+  expect(screen.getByText('Subjects')).toBeInTheDocument();
+  expect(screen.getByLabelText('Mouse-A1')).toBeInTheDocument();
+  expect(screen.getByLabelText('Mouse-B1')).toBeInTheDocument();
+  fireEvent.click(screen.getByText('◂ Subjects'));
+  expect(screen.queryByText('Subjects')).toBeNull();
+});
+
+it('unchecking a subject in the sidebar persists across re-render', () => {
+  renderChart();
+  fireEvent.click(screen.getByText('▸ Subjects'));
+  const cb = screen.getByLabelText('Mouse-A1');
+  expect(cb.checked).toBe(true);
+  fireEvent.click(cb);
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(false);
+  expect(screen.getByText('Show all')).toBeInTheDocument();
+});
+
+it('hydrates hidden subjects and sidebar-open from plotConfig', () => {
+  render(
+    <ExperimentAnalysisCharts
+      animals={ANIMALS}
+      experimentStatuses={STATUSES}
+      subjectTemplate={SUBJECT_TEMPLATE}
+      dailyTemplate={DAILY_TEMPLATE}
+      plotConfig={{ hiddenSubjects: ['a1'], sidebarOpen: true }}
+    />,
+  );
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(false);
+  expect(screen.getByLabelText('Mouse-B1').checked).toBe(true);
+});
+
+describe('debounced auto-save', () => {
+  beforeEach(() => jest.useFakeTimers());
+  afterEach(() => jest.useRealTimers());
+
+  it('does not call onPersistConfig on initial render', () => {
+    const onPersist = jest.fn();
+    render(
+      <ExperimentAnalysisCharts
+        animals={ANIMALS} experimentStatuses={STATUSES}
+        subjectTemplate={SUBJECT_TEMPLATE} dailyTemplate={DAILY_TEMPLATE}
+        plotConfig={null} onPersistConfig={onPersist}
+      />,
+    );
+    act(() => { jest.advanceTimersByTime(1500); });
+    expect(onPersist).not.toHaveBeenCalled();
+  });
+
+  it('calls onPersistConfig ~1s after a change, with the updated config', () => {
+    const onPersist = jest.fn().mockResolvedValue({});
+    render(
+      <ExperimentAnalysisCharts
+        animals={ANIMALS} experimentStatuses={STATUSES}
+        subjectTemplate={SUBJECT_TEMPLATE} dailyTemplate={DAILY_TEMPLATE}
+        plotConfig={{ sidebarOpen: true }} onPersistConfig={onPersist}
+      />,
+    );
+    fireEvent.click(screen.getByLabelText('Mouse-A1'));
+    expect(onPersist).not.toHaveBeenCalled();
+    act(() => { jest.advanceTimersByTime(1100); });
+    expect(onPersist).toHaveBeenCalledTimes(1);
+    expect(onPersist.mock.calls[0][0].hiddenSubjects).toContain('a1');
+  });
+
+  it('does not save and clears the saving hint when a change is reverted before the debounce fires', () => {
+    const onPersist = jest.fn().mockResolvedValue({});
+    render(
+      <ExperimentAnalysisCharts
+        animals={ANIMALS} experimentStatuses={STATUSES}
+        subjectTemplate={SUBJECT_TEMPLATE} dailyTemplate={DAILY_TEMPLATE}
+        plotConfig={{ sidebarOpen: true }} onPersistConfig={onPersist}
+      />,
+    );
+    fireEvent.click(screen.getByLabelText('Mouse-A1')); // hide a1
+    expect(screen.getByText('Saving…')).toBeInTheDocument();
+    fireEvent.click(screen.getByLabelText('Mouse-A1')); // revert before the 1s timer
+    act(() => { jest.advanceTimersByTime(1100); });
+    expect(onPersist).not.toHaveBeenCalled();
+    expect(screen.queryByText('Saving…')).toBeNull();
+  });
+});

frontend/tests/ExperimentCalendar.test.jsx

@@ -0,0 +1,186 @@
+import React from 'react';
+import { render, screen, fireEvent } from '@testing-library/react';
+import ExperimentCalendar from '../src/components/ExperimentCalendar';
+
+const mockNavigate = jest.fn();
+jest.mock('react-router-dom', () => ({
+  useNavigate: () => mockNavigate,
+}));
+
+const EXP_ID = 'aaaaaaaa-0000-0000-0000-000000000001';
+
+const TEMPLATE = [
+  { fieldId: '00000000-0000-0000-0000-000000000002', key: 'vitals',   label: 'Vitals',   active: true,  builtin: true  },
+  { fieldId: 'ww000000-0000-0000-0000-000000000099', key: 'weights',  label: 'Weights',  active: true,  builtin: false },
+  { fieldId: 'zz000000-0000-0000-0000-000000000001', key: 'notes',    label: 'Notes',    active: false, builtin: true  },
+];
+
+function todayStr() {
+  const d = new Date();
+  return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`;
+}
+
+function makeStatus(animalId, date, customFields = {}, vitals = null) {
+  return {
+    id: `s-${animalId}-${date}`,
+    animal_id: animalId,
+    date: `${date}T00:00:00.000Z`,
+    experiment_description: null,
+    vitals,
+    treatment: null,
+    notes: null,
+    custom_fields: customFields,
+    analysis_summary: null,
+  };
+}
+
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+// ── Rendering ──────────────────────────────────────────────────────────────────
+
+describe('ExperimentCalendar rendering', () => {
+  it('renders the current month and year', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    const now = new Date();
+    const monthLabel = now.toLocaleString('en-US', { month: 'long', year: 'numeric' });
+    expect(screen.getByText(monthLabel)).toBeInTheDocument();
+  });
+
+  it('renders day-of-week headers', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    for (const d of ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat']) {
+      expect(screen.getByText(d)).toBeInTheDocument();
+    }
+  });
+
+  it('renders the field selector with active template fields only', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    const options = screen.getAllByRole('option').map((o) => o.textContent);
+    expect(options).toContain('Vitals');
+    expect(options).toContain('Weights');
+    expect(options).not.toContain('Notes'); // inactive
+  });
+});
+
+// ── Default field selection ────────────────────────────────────────────────────
+
+describe('default field selection', () => {
+  it('defaults to the field whose label contains "weight"', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    expect(screen.getByTestId('field-select')).toHaveValue('ww000000-0000-0000-0000-000000000099');
+  });
+
+  it('defaults to first field if none contains "weight"', () => {
+    const noWeightTemplate = [
+      { fieldId: 'ff000000-0000-0000-0000-000000000001', key: 'treatment', label: 'Treatment', active: true, builtin: true },
+      { fieldId: 'ff000000-0000-0000-0000-000000000002', key: 'vitals',    label: 'Vitals',    active: true, builtin: true },
+    ];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={noWeightTemplate} allStatuses={[]} />);
+    expect(screen.getByTestId('field-select')).toHaveValue('treatment');
+  });
+});
+
+// ── Count badges (computed from allStatuses) ───────────────────────────────────
+
+describe('count badges', () => {
+  it('shows a count badge for a day where the selected field is non-empty', () => {
+    const dateStr = todayStr();
+    const statuses = [
+      makeStatus('a1', dateStr, { 'ww000000-0000-0000-0000-000000000099': '325' }),
+      makeStatus('a2', dateStr, { 'ww000000-0000-0000-0000-000000000099': '310' }),
+    ];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={statuses} />);
+    expect(screen.getByTestId(`count-${dateStr}`)).toHaveTextContent('2');
+  });
+
+  it('does not show count badge on days with no data', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    expect(screen.queryByTestId(`count-${todayStr()}`)).not.toBeInTheDocument();
+  });
+
+  it('shows a count badge for builtin field (vitals)', () => {
+    const dateStr = todayStr();
+    const statuses = [makeStatus('a1', dateStr, {}, 'HR 72')];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={statuses} />);
+    fireEvent.change(screen.getByTestId('field-select'), { target: { value: 'vitals' } });
+    expect(screen.getByTestId(`count-${dateStr}`)).toHaveTextContent('1');
+  });
+
+  it('recomputes counts after field change', () => {
+    const dateStr = todayStr();
+    const statuses = [makeStatus('a1', dateStr, {}, 'HR 72')];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={statuses} />);
+    // Default is weights — no badge
+    expect(screen.queryByTestId(`count-${dateStr}`)).not.toBeInTheDocument();
+    // Switch to vitals — badge appears
+    fireEvent.change(screen.getByTestId('field-select'), { target: { value: 'vitals' } });
+    expect(screen.getByTestId(`count-${dateStr}`)).toHaveTextContent('1');
+  });
+});
+
+// ── Month navigation ──────────────────────────────────────────────────────────
+
+describe('month navigation', () => {
+  it('moves to the previous month on ‹ click', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    const now  = new Date();
+    const prev = new Date(now.getFullYear(), now.getMonth() - 1, 1);
+    const prevLabel = prev.toLocaleString('en-US', { month: 'long', year: 'numeric' });
+    fireEvent.click(screen.getByLabelText('Previous month'));
+    expect(screen.getByText(prevLabel)).toBeInTheDocument();
+  });
+
+  it('moves to the next month on › click', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    const now  = new Date();
+    const next = new Date(now.getFullYear(), now.getMonth() + 1, 1);
+    const nextLabel = next.toLocaleString('en-US', { month: 'long', year: 'numeric' });
+    fireEvent.click(screen.getByLabelText('Next month'));
+    expect(screen.getByText(nextLabel)).toBeInTheDocument();
+  });
+});
+
+// ── Day click navigation ──────────────────────────────────────────────────────
+
+describe('day click navigation', () => {
+  it('navigates to the day view with field param when a day with data is clicked', () => {
+    const dateStr = todayStr();
+    const statuses = [
+      makeStatus('a1', dateStr, { 'ww000000-0000-0000-0000-000000000099': '325' }),
+    ];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={statuses} />);
+    fireEvent.click(screen.getByTestId(`day-${dateStr}`));
+    expect(mockNavigate).toHaveBeenCalledWith(
+      `/experiments/${EXP_ID}/day/${dateStr}?field=ww000000-0000-0000-0000-000000000099`,
+    );
+  });
+
+  it('does not navigate when clicking a day without data (button is disabled)', () => {
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={[]} />);
+    const dayBtn = screen.getByTestId(`day-${todayStr()}`);
+    expect(dayBtn).toBeDisabled();
+    fireEvent.click(dayBtn);
+    expect(mockNavigate).not.toHaveBeenCalled();
+  });
+
+  it('includes the currently selected field in the navigation URL', () => {
+    const dateStr = todayStr();
+    const statuses = [makeStatus('a1', dateStr, {}, 'HR 72')];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={TEMPLATE} allStatuses={statuses} />);
+    // Switch to vitals field first
+    fireEvent.change(screen.getByTestId('field-select'), { target: { value: 'vitals' } });
+    fireEvent.click(screen.getByTestId(`day-${dateStr}`));
+    expect(mockNavigate).toHaveBeenCalledWith(
+      `/experiments/${EXP_ID}/day/${dateStr}?field=vitals`,
+    );
+  });
+
+  it('navigates with no field param when selectedField is null (no active fields)', () => {
+    const emptyTemplate = [];
+    render(<ExperimentCalendar experimentId={EXP_ID} template={emptyTemplate} allStatuses={[]} />);
+    // No days have data with empty template, so nothing to click — just verify no crash
+    expect(screen.queryByTestId(`count-${todayStr()}`)).not.toBeInTheDocument();
+  });
+});

frontend/tests/ExperimentDayView.test.jsx

@@ -0,0 +1,639 @@
+import React from 'react';
+import { render, screen, fireEvent, waitFor, within } from '@testing-library/react';
+import ExperimentDayView from '../src/pages/ExperimentDayView';
+
+// ── Mocks ──────────────────────────────────────────────────────────────────────
+
+const mockNavigate = jest.fn();
+jest.mock('react-router-dom', () => ({
+  useParams: jest.fn(),
+  useSearchParams: jest.fn(),
+  useNavigate: () => mockNavigate,
+  Link: ({ to, children, ...props }) => <a href={to} {...props}>{children}</a>,
+}));
+const { useParams, useSearchParams } = require('react-router-dom');
+const { experimentsApi, dailyStatusesApi } = require('../src/api/client');
+
+jest.mock('../src/api/client', () => ({
+  experimentsApi: {
+    get: jest.fn(),
+    getDayStatuses: jest.fn(),
+    getCalendar: jest.fn(),
+  },
+  dailyStatusesApi: {
+    update: jest.fn(),
+  },
+}));
+
+// DailyStatusForm is a complex form component; stub it to keep tests focused
+jest.mock('../src/components/DailyStatusForm', () =>
+  function MockDailyStatusForm({ onSuccess, onCancel }) {
+    return (
+      <div data-testid="daily-status-form">
+        <button onClick={() => onSuccess({ id: 'updated-id' })}>Submit</button>
+        <button onClick={onCancel}>Cancel</button>
+      </div>
+    );
+  }
+);
+
+// recharts uses ResizeObserver which is not available in jsdom
+jest.mock('recharts', () => ({
+  ResponsiveContainer: ({ children }) => <div>{children}</div>,
+  BarChart: ({ children }) => <div data-testid="bar-chart">{children}</div>,
+  Bar: () => null,
+  XAxis: () => null,
+  YAxis: () => null,
+  CartesianGrid: () => null,
+  Tooltip: () => null,
+  Legend: () => null,
+}));
+
+// ── Fixtures ───────────────────────────────────────────────────────────────────
+
+const EXP_ID   = 'exp-0001-0000-0000-0000-000000000001';
+const DATE_STR = '2026-04-23';
+const FIELD_ID = 'ww000000-0000-0000-0000-000000000099';
+
+const TEMPLATE = [
+  { fieldId: '00000000-0000-0000-0000-000000000001', key: 'vitals',   label: 'Vitals',   type: 'text',     builtin: true,  active: true },
+  { fieldId: FIELD_ID,                               key: 'weight',   label: 'Weight',   type: 'text',     builtin: false, active: true  },
+  { fieldId: 'zz000000-0000-0000-0000-000000000001', key: 'notes',    label: 'Notes',    type: 'textarea', builtin: true,  active: false },
+];
+
+const ANIMALS = [
+  { id: 'a1000000-0000-0000-0000-000000000001', animal_name: 'Rat A', animal_id_string: 'R001' },
+  { id: 'a2000000-0000-0000-0000-000000000002', animal_name: 'Rat B', animal_id_string: 'R002' },
+  { id: 'a3000000-0000-0000-0000-000000000003', animal_name: 'Rat C', animal_id_string: 'R003' },
+];
+
+const EXPERIMENT = {
+  id: EXP_ID,
+  title: 'Reach Task Study',
+  template: TEMPLATE,
+  animals: ANIMALS,
+};
+
+function makeStatus(animalId, overrides = {}) {
+  return {
+    id: `status-${animalId}`,
+    animal_id: animalId,
+    date: `${DATE_STR}T00:00:00.000Z`,
+    experiment_description: null,
+    vitals: null,
+    treatment: null,
+    notes: null,
+    custom_fields: {},
+    analysis_summary: null,
+    ...overrides,
+  };
+}
+
+function makeSearchParams(field = FIELD_ID) {
+  const params = new URLSearchParams(field ? `field=${field}` : '');
+  return [params, jest.fn()];
+}
+
+// ── Setup ──────────────────────────────────────────────────────────────────────
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  useParams.mockReturnValue({ id: EXP_ID, date: DATE_STR });
+  useSearchParams.mockReturnValue(makeSearchParams(FIELD_ID));
+  experimentsApi.get.mockResolvedValue(EXPERIMENT);
+  experimentsApi.getDayStatuses.mockResolvedValue([]);
+  experimentsApi.getCalendar.mockResolvedValue({ field: FIELD_ID, days: {} });
+  dailyStatusesApi.update.mockResolvedValue({});
+});
+
+// ── Loading & error states ────────────────────────────────────────────────────
+
+describe('loading and error states', () => {
+  it('shows a loading indicator while data is being fetched', () => {
+    experimentsApi.get.mockReturnValue(new Promise(() => {})); // never resolves
+    render(<ExperimentDayView />);
+    expect(screen.getByText(/loading/i)).toBeInTheDocument();
+  });
+
+  it('shows an error message when the API call fails', async () => {
+    experimentsApi.get.mockRejectedValue({ message: 'Network error' });
+    render(<ExperimentDayView />);
+    await waitFor(() => expect(screen.getByText(/network error/i)).toBeInTheDocument());
+  });
+
+  it('shows empty state when no data for the day', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() =>
+      expect(screen.getByText(/no data recorded for this day/i)).toBeInTheDocument()
+    );
+  });
+});
+
+// ── Breadcrumb ────────────────────────────────────────────────────────────────
+
+describe('breadcrumb', () => {
+  it('renders dashboard, experiment title, and formatted date', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Reach Task Study'));
+    expect(screen.getByRole('link', { name: 'Dashboard' })).toHaveAttribute('href', '/');
+    expect(screen.getByRole('link', { name: 'Reach Task Study' })).toHaveAttribute('href', `/experiments/${EXP_ID}`);
+    expect(screen.getAllByText('April 23, 2026').length).toBeGreaterThan(0);
+  });
+});
+
+// ── Row filtering by selected field ──────────────────────────────────────────
+
+describe('row filtering', () => {
+  it('shows animals that have a non-empty value for the selected field', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: '325' } }),
+      makeStatus('a2000000-0000-0000-0000-000000000002', { custom_fields: { [FIELD_ID]: '310' } }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByText('Rat A')).toBeInTheDocument();
+    expect(screen.getByText('Rat B')).toBeInTheDocument();
+  });
+
+  it('excludes animals whose selected field value is empty', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: '325' } }),
+      makeStatus('a2000000-0000-0000-0000-000000000002', { custom_fields: {} }), // no weight
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.queryByText('Rat B')).not.toBeInTheDocument();
+  });
+
+  it('excludes animals whose selected field value is null', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: null } }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() =>
+      expect(screen.getByText(/no data recorded/i)).toBeInTheDocument()
+    );
+  });
+
+  it('excludes animals with no status record for that day', async () => {
+    // Only Rat A has a status; Rat B and C have no record returned
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: '325' } }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.queryByText('Rat B')).not.toBeInTheDocument();
+    expect(screen.queryByText('Rat C')).not.toBeInTheDocument();
+  });
+
+  it('shows all animals with a status record when no field filter is set', async () => {
+    useSearchParams.mockReturnValue(makeSearchParams(null));
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001'),
+      makeStatus('a2000000-0000-0000-0000-000000000002'),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByText('Rat A')).toBeInTheDocument();
+    expect(screen.getByText('Rat B')).toBeInTheDocument();
+  });
+
+  it('filters by builtin field (vitals)', async () => {
+    useSearchParams.mockReturnValue(makeSearchParams('vitals'));
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { vitals: 'HR 72' }),
+      makeStatus('a2000000-0000-0000-0000-000000000002', { vitals: null }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.queryByText('Rat B')).not.toBeInTheDocument();
+  });
+});
+
+// ── Table structure ───────────────────────────────────────────────────────────
+
+describe('table structure', () => {
+  beforeEach(() => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        vitals: 'HR 72',
+        custom_fields: { [FIELD_ID]: '325' },
+      }),
+    ]);
+  });
+
+  it('renders a column header for each active template field', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    // Active fields: Vitals, Weight. Notes is inactive.
+    expect(screen.getByText('Vitals')).toBeInTheDocument();
+    expect(screen.getByText('Weight')).toBeInTheDocument();
+    expect(screen.queryByText('Notes')).not.toBeInTheDocument();
+  });
+
+  it('renders field values in the correct cells', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    expect(screen.getByText('HR 72')).toBeInTheDocument();
+    expect(screen.getByText('325')).toBeInTheDocument();
+  });
+
+  it('renders dash for empty field values', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        vitals: null,
+        custom_fields: { [FIELD_ID]: '325' },
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByText('—')).toBeInTheDocument();
+  });
+
+  it('renders the subject name with animal_id_string alongside', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByText('R001')).toBeInTheDocument();
+  });
+
+  it('renders an Edit button for each row', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByRole('button', { name: /edit/i })).toBeInTheDocument();
+  });
+});
+
+// ── Subject name navigation ───────────────────────────────────────────────────
+
+describe('subject name click', () => {
+  it('navigates to /daily-statuses/:id when subject name is clicked', async () => {
+    const statusId = 'status-a1000000-0000-0000-0000-000000000001';
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: '325' } }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    fireEvent.click(screen.getByText('Rat A'));
+    expect(mockNavigate).toHaveBeenCalledWith(`/daily-statuses/${statusId}`);
+  });
+});
+
+// ── Edit modal ────────────────────────────────────────────────────────────────
+
+describe('edit modal', () => {
+  beforeEach(() => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', { custom_fields: { [FIELD_ID]: '325' } }),
+    ]);
+  });
+
+  it('opens the edit modal when Edit button is clicked', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    fireEvent.click(screen.getByRole('button', { name: /edit/i }));
+    await waitFor(() =>
+      expect(screen.getByTestId('daily-status-form')).toBeInTheDocument()
+    );
+  });
+
+  it('closes the edit modal when Cancel is clicked', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    fireEvent.click(screen.getByRole('button', { name: /edit/i }));
+    await waitFor(() => screen.getByTestId('daily-status-form'));
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    await waitFor(() =>
+      expect(screen.queryByTestId('daily-status-form')).not.toBeInTheDocument()
+    );
+  });
+
+  it('closes the edit modal and updates the row after successful submit', async () => {
+    const originalStatus = makeStatus('a1000000-0000-0000-0000-000000000001', {
+      custom_fields: { [FIELD_ID]: '325' },
+    });
+    experimentsApi.getDayStatuses.mockResolvedValue([originalStatus]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    fireEvent.click(screen.getByRole('button', { name: /edit/i }));
+    await waitFor(() => screen.getByTestId('daily-status-form'));
+    // Submit with updated status
+    fireEvent.click(screen.getByRole('button', { name: /submit/i }));
+    await waitFor(() =>
+      expect(screen.queryByTestId('daily-status-form')).not.toBeInTheDocument()
+    );
+  });
+});
+
+// ── Session metrics bar chart ─────────────────────────────────────────────────
+//
+// Bar chart reads from status.analysis_summary — pre-computed trial-level
+// session metrics: { total, counts: { Success, Failure }, success_rate }
+// X-axis: animals visible in the table (have non-empty selected field value).
+// Hidden when no visible animal has analysis_summary.total > 0.
+
+describe('session metrics bar chart', () => {
+  it('renders bar chart when at least one visible animal has analysis_summary', async () => {
+    const summary = { total: 18, counts: { Success: 5, Failure: 13 }, success_rate: 0.28 };
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        analysis_summary: summary,
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByTestId('bar-chart')).toBeInTheDocument();
+  });
+
+  it('hides bar chart when no visible animal has analysis_summary', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        analysis_summary: null,
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.queryByTestId('bar-chart')).not.toBeInTheDocument();
+  });
+
+  it('hides bar chart when analysis_summary.total is 0', async () => {
+    const emptySummary = { total: 0, counts: { Success: 0, Failure: 0 }, success_rate: null };
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        analysis_summary: emptySummary,
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.queryByTestId('bar-chart')).not.toBeInTheDocument();
+  });
+
+  it('excludes from chart animals that are filtered out by the selected field', async () => {
+    // Rat A: has field value + analysis_summary → in table and chart
+    // Rat B: NO field value, has analysis_summary → excluded from both
+    const summary = { total: 10, counts: { Success: 7, Failure: 3 }, success_rate: 0.7 };
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        analysis_summary: summary,
+      }),
+      makeStatus('a2000000-0000-0000-0000-000000000002', {
+        custom_fields: {},
+        analysis_summary: summary,
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    // Chart still renders because Rat A has data
+    expect(screen.getByTestId('bar-chart')).toBeInTheDocument();
+    // Rat B not in table
+    expect(screen.queryByText('Rat B')).not.toBeInTheDocument();
+  });
+
+  it('shows bar chart for multiple animals each with their own analysis_summary', async () => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        analysis_summary: { total: 18, counts: { Success: 5, Failure: 13 }, success_rate: 0.28 },
+      }),
+      makeStatus('a2000000-0000-0000-0000-000000000002', {
+        custom_fields: { [FIELD_ID]: '310' },
+        analysis_summary: { total: 10, counts: { Success: 7, Failure: 3 }, success_rate: 0.7 },
+      }),
+    ]);
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    expect(screen.getByText('Rat B')).toBeInTheDocument();
+    expect(screen.getByTestId('bar-chart')).toBeInTheDocument();
+  });
+});
+
+// ── API call parameters ───────────────────────────────────────────────────────
+
+describe('API calls', () => {
+  it('calls getDayStatuses with the experiment id and date from the URL', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() =>
+      expect(experimentsApi.getDayStatuses).toHaveBeenCalledWith(EXP_ID, DATE_STR)
+    );
+  });
+
+  it('calls experimentsApi.get with the experiment id', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() =>
+      expect(experimentsApi.get).toHaveBeenCalledWith(EXP_ID)
+    );
+  });
+
+  it('calls getCalendar with experiment id and selected field for day navigation', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() =>
+      expect(experimentsApi.getCalendar).toHaveBeenCalledWith(EXP_ID, FIELD_ID)
+    );
+  });
+});
+
+// ── Inline cell editing ───────────────────────────────────────────────────────
+
+describe('inline cell editing', () => {
+  const STATUS_ID = 'status-a1000000-0000-0000-0000-000000000001';
+
+  beforeEach(() => {
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        vitals: 'HR 72',
+      }),
+    ]);
+    dailyStatusesApi.update.mockResolvedValue(
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '330' },
+        vitals: 'HR 72',
+      })
+    );
+  });
+
+  it('shows an input when a cell value is clicked', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    fireEvent.click(screen.getByText('325'));
+    expect(screen.getByRole('textbox')).toBeInTheDocument();
+  });
+
+  it('shows an input when a dash (empty cell) is clicked', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('Rat A'));
+    // Vitals is shown as "HR 72" but weight is selected, click on a dash cell in vitals column
+    // After the status above vitals = 'HR 72' (not empty), let's use a status without vitals
+    experimentsApi.getDayStatuses.mockResolvedValue([
+      makeStatus('a1000000-0000-0000-0000-000000000001', {
+        custom_fields: { [FIELD_ID]: '325' },
+        vitals: null,
+      }),
+    ]);
+    // Re-render
+    const { unmount } = render(<ExperimentDayView />);
+    await waitFor(() => screen.getAllByText('Rat A'));
+    const dashCell = screen.getAllByText('—')[0];
+    fireEvent.click(dashCell);
+    expect(screen.getByRole('textbox')).toBeInTheDocument();
+    unmount();
+  });
+
+  it('saves a custom field value on Enter key', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    fireEvent.click(screen.getByText('325'));
+    const input = screen.getByRole('textbox');
+    fireEvent.change(input, { target: { value: '330' } });
+    fireEvent.keyDown(input, { key: 'Enter' });
+    await waitFor(() =>
+      expect(dailyStatusesApi.update).toHaveBeenCalledWith(
+        STATUS_ID,
+        expect.objectContaining({ custom_fields: expect.objectContaining({ [FIELD_ID]: '330' }) })
+      )
+    );
+  });
+
+  it('saves on blur', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    fireEvent.click(screen.getByText('325'));
+    const input = screen.getByRole('textbox');
+    fireEvent.change(input, { target: { value: '328' } });
+    fireEvent.blur(input);
+    await waitFor(() =>
+      expect(dailyStatusesApi.update).toHaveBeenCalledWith(
+        STATUS_ID,
+        expect.objectContaining({ custom_fields: expect.objectContaining({ [FIELD_ID]: '328' }) })
+      )
+    );
+  });
+
+  it('cancels edit on Escape without saving', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    fireEvent.click(screen.getByText('325'));
+    const input = screen.getByRole('textbox');
+    fireEvent.change(input, { target: { value: '999' } });
+    fireEvent.keyDown(input, { key: 'Escape' });
+    expect(dailyStatusesApi.update).not.toHaveBeenCalled();
+    await waitFor(() => expect(screen.queryByRole('textbox')).not.toBeInTheDocument());
+  });
+
+  it('skips the API call when the value is unchanged', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('325'));
+    fireEvent.click(screen.getByText('325'));
+    const input = screen.getByRole('textbox');
+    // value unchanged — blur without editing
+    fireEvent.blur(input);
+    expect(dailyStatusesApi.update).not.toHaveBeenCalled();
+  });
+
+  it('saves a builtin field (vitals) with the field key as payload key', async () => {
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText('HR 72'));
+    fireEvent.click(screen.getByText('HR 72'));
+    const input = screen.getByRole('textbox');
+    fireEvent.change(input, { target: { value: 'HR 80' } });
+    fireEvent.keyDown(input, { key: 'Enter' });
+    await waitFor(() =>
+      expect(dailyStatusesApi.update).toHaveBeenCalledWith(
+        STATUS_ID,
+        expect.objectContaining({ vitals: 'HR 80' })
+      )
+    );
+    // custom_fields must NOT be in the payload for a builtin field
+    const payload = dailyStatusesApi.update.mock.calls[0][1];
+    expect(payload).not.toHaveProperty('custom_fields');
+  });
+});
+
+// ── Prev / next day navigation ────────────────────────────────────────────────
+
+describe('prev/next day navigation', () => {
+  it('shows no navigation buttons when there are no other days', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { [DATE_STR]: 2 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => expect(experimentsApi.getCalendar).toHaveBeenCalled());
+    expect(screen.queryByText(/← April/)).not.toBeInTheDocument();
+    expect(screen.queryByText(/April.*→/)).not.toBeInTheDocument();
+  });
+
+  it('shows a previous day button when an earlier day has data', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { '2026-04-22': 1, [DATE_STR]: 2 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/April 22, 2026/));
+    expect(screen.getByText(/← April 22, 2026/)).toBeInTheDocument();
+  });
+
+  it('shows a next day button when a later day has data', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { [DATE_STR]: 2, '2026-04-24': 1 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/April 24, 2026/));
+    expect(screen.getByText(/April 24, 2026 →/)).toBeInTheDocument();
+  });
+
+  it('shows both prev and next buttons when surrounded by days with data', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { '2026-04-21': 1, [DATE_STR]: 2, '2026-04-25': 3 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/April 21, 2026/));
+    expect(screen.getByText(/← April 21, 2026/)).toBeInTheDocument();
+    expect(screen.getByText(/April 25, 2026 →/)).toBeInTheDocument();
+  });
+
+  it('navigates to the previous day with the field param preserved', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { '2026-04-22': 1, [DATE_STR]: 2 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/← April 22, 2026/));
+    fireEvent.click(screen.getByText(/← April 22, 2026/));
+    expect(mockNavigate).toHaveBeenCalledWith(
+      `/experiments/${EXP_ID}/day/2026-04-22?field=${FIELD_ID}`
+    );
+  });
+
+  it('navigates to the next day with the field param preserved', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { [DATE_STR]: 2, '2026-04-24': 1 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/April 24, 2026 →/));
+    fireEvent.click(screen.getByText(/April 24, 2026 →/));
+    expect(mockNavigate).toHaveBeenCalledWith(
+      `/experiments/${EXP_ID}/day/2026-04-24?field=${FIELD_ID}`
+    );
+  });
+
+  it('only shows adjacent days, not all days (prev is immediately before in sorted list)', async () => {
+    experimentsApi.getCalendar.mockResolvedValue({
+      field: FIELD_ID,
+      days: { '2026-04-10': 1, '2026-04-20': 2, [DATE_STR]: 3, '2026-04-30': 1 },
+    });
+    render(<ExperimentDayView />);
+    await waitFor(() => screen.getByText(/April 20, 2026/));
+    // Prev should be April 20 (immediately before), not April 10
+    expect(screen.getByText(/← April 20, 2026/)).toBeInTheDocument();
+    expect(screen.queryByText(/April 10/)).not.toBeInTheDocument();
+    // Next should be April 30 (immediately after)
+    expect(screen.getByText(/April 30, 2026 →/)).toBeInTheDocument();
+  });
+});

frontend/tests/ExperimentForm.test.jsx

@@ -0,0 +1,105 @@
+import React from 'react';
+import { render, screen, fireEvent, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import ExperimentForm from '../src/components/ExperimentForm';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  experimentsApi: {
+    create: jest.fn(),
+    update: jest.fn(),
+  },
+}));
+
+const onSuccess = jest.fn();
+const onCancel = jest.fn();
+
+beforeEach(() => {
+  jest.clearAllMocks();
+});
+
+describe('ExperimentForm', () => {
+  it('renders title input and submit button', () => {
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    expect(screen.getByLabelText(/experiment title/i)).toBeInTheDocument();
+    expect(screen.getByRole('button', { name: /create experiment/i })).toBeInTheDocument();
+  });
+
+  it('shows validation error when submitting empty title', async () => {
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    fireEvent.click(screen.getByRole('button', { name: /create experiment/i }));
+    expect(await screen.findByRole('alert')).toHaveTextContent(/title is required/i);
+    expect(client.experimentsApi.create).not.toHaveBeenCalled();
+  });
+
+  it('shows error when title exceeds 255 chars', async () => {
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    await userEvent.type(screen.getByLabelText(/experiment title/i), 'x'.repeat(256));
+    fireEvent.click(screen.getByRole('button', { name: /create experiment/i }));
+    expect(await screen.findByRole('alert')).toHaveTextContent(/255/i);
+    expect(client.experimentsApi.create).not.toHaveBeenCalled();
+  });
+
+  it('calls create API with trimmed title and calls onSuccess', async () => {
+    const experiment = { id: 'abc-123', title: 'New Study' };
+    client.experimentsApi.create.mockResolvedValue(experiment);
+
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    await userEvent.type(screen.getByLabelText(/experiment title/i), 'New Study');
+    fireEvent.click(screen.getByRole('button', { name: /create experiment/i }));
+
+    await waitFor(() => expect(client.experimentsApi.create).toHaveBeenCalledWith({ title: 'New Study' }));
+    await waitFor(() => expect(onSuccess).toHaveBeenCalledWith(experiment));
+  });
+
+  it('shows "Save Changes" button for existing experiment', () => {
+    render(
+      <ExperimentForm
+        existing={{ id: 'abc', title: 'Old Title' }}
+        onSuccess={onSuccess}
+        onCancel={onCancel}
+      />
+    );
+    expect(screen.getByRole('button', { name: /save changes/i })).toBeInTheDocument();
+    expect(screen.getByDisplayValue('Old Title')).toBeInTheDocument();
+  });
+
+  it('calls update API for existing experiment', async () => {
+    const updated = { id: 'abc', title: 'Updated Title' };
+    client.experimentsApi.update.mockResolvedValue(updated);
+
+    render(
+      <ExperimentForm
+        existing={{ id: 'abc', title: 'Old Title' }}
+        onSuccess={onSuccess}
+        onCancel={onCancel}
+      />
+    );
+
+    const input = screen.getByDisplayValue('Old Title');
+    await userEvent.clear(input);
+    await userEvent.type(input, 'Updated Title');
+    fireEvent.click(screen.getByRole('button', { name: /save changes/i }));
+
+    await waitFor(() =>
+      expect(client.experimentsApi.update).toHaveBeenCalledWith('abc', { title: 'Updated Title' })
+    );
+    await waitFor(() => expect(onSuccess).toHaveBeenCalledWith(updated));
+  });
+
+  it('calls onCancel when Cancel is clicked', () => {
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    expect(onCancel).toHaveBeenCalled();
+  });
+
+  it('shows API error when create fails', async () => {
+    client.experimentsApi.create.mockRejectedValue({ message: 'Server error', details: null });
+
+    render(<ExperimentForm onSuccess={onSuccess} onCancel={onCancel} />);
+    await userEvent.type(screen.getByLabelText(/experiment title/i), 'Test');
+    fireEvent.click(screen.getByRole('button', { name: /create experiment/i }));
+
+    expect(await screen.findByRole('alert')).toHaveTextContent(/server error/i);
+  });
+});

frontend/tests/ExportDataModal.test.jsx

@@ -0,0 +1,124 @@
+import React from 'react';
+import { render, screen, waitFor, fireEvent } from '@testing-library/react';
+import ExportDataModal from '../src/components/ExportDataModal';
+import * as client from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  experimentsApi: { getDailyStatuses: jest.fn() },
+}));
+
+const animals = [
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+];
+const statuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5, success_rate: 0.5 } },
+  { animal_id: 'a1', date: '2026-07-02T00:00:00Z', analysis_summary: { total: 7, success_rate: 0.7 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 9, success_rate: 0.9 } },
+];
+const subjectTemplate = [{ fieldId: 'grp', label: 'Group', active: true }];
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  client.experimentsApi.getDailyStatuses.mockResolvedValue(statuses);
+});
+
+// Intercept the Blob handed to URL.createObjectURL so tests can read the real CSV.
+// Also stub anchor.click() — jsdom treats a click on <a href="blob:..."> as an
+// unimplemented navigation that throws async and can flake a later test.
+function mockDownload() {
+  let blob = null;
+  const origCreate = global.URL.createObjectURL;
+  const origRevoke = global.URL.revokeObjectURL;
+  const origClick = window.HTMLAnchorElement.prototype.click;
+  global.URL.createObjectURL = jest.fn((b) => { blob = b; return 'blob:mock'; });
+  global.URL.revokeObjectURL = jest.fn();
+  window.HTMLAnchorElement.prototype.click = jest.fn();
+  return {
+    getBlob: () => blob,
+    restore: async () => {
+      await new Promise((r) => setTimeout(r, 0)); // flush handleExport's setTimeout revoke
+      global.URL.createObjectURL = origCreate;
+      global.URL.revokeObjectURL = origRevoke;
+      window.HTMLAnchorElement.prototype.click = origClick;
+    },
+  };
+}
+
+function readBlobText(blob) {
+  return new Promise((resolve, reject) => {
+    const fr = new FileReader();
+    fr.onload = () => resolve(fr.result);
+    fr.onerror = reject;
+    fr.readAsText(blob);
+  });
+}
+
+function renderModal(props = {}) {
+  return render(
+    <ExportDataModal
+      experimentId="exp-1"
+      experimentTitle="My Study"
+      dailyTemplate={[]}
+      animals={animals}
+      subjectTemplate={subjectTemplate}
+      groupField="__none__"
+      onClose={jest.fn()}
+      {...props}
+    />,
+  );
+}
+
+describe('ExportDataModal', () => {
+  it('renders X / Data / Group by pickers; X defaults to Date', async () => {
+    renderModal();
+    expect(await screen.findByLabelText('X axis (rows)')).toHaveValue('__date__');
+    expect(screen.getByLabelText('Data (cells)')).toBeInTheDocument();
+    expect(screen.getByLabelText('Group by')).toHaveValue('__none__');
+    await waitFor(() => expect(screen.getByText(/2 rows × 2 subjects/i)).toBeInTheDocument());
+  });
+
+  it('default export (X=Date, Data=Total attempts) has subject columns, date rows, blank where missing', async () => {
+    const dl = mockDownload();
+    renderModal();
+    await screen.findByLabelText('X axis (rows)');
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toBe('Data,Total attempts\n\nDate,Alpha,Beta\n2026-07-01,5,9\n2026-07-02,7,');
+    await dl.restore();
+  });
+
+  it('switching X to # Days Reach makes rows the day ordinals', async () => {
+    const dl = mockDownload();
+    renderModal();
+    fireEvent.change(await screen.findByLabelText('X axis (rows)'), { target: { value: '__days__' } });
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toBe('Data,Total attempts\n\n# Days Reach (ordinal),Alpha,Beta\n1,5,9\n2,7,');
+    await dl.restore();
+  });
+
+  it('a valid group field adds a Group row and clusters subjects', async () => {
+    const dl = mockDownload();
+    renderModal({ groupField: 'grp' });
+    await screen.findByLabelText('X axis (rows)');
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).toMatch(/^Group,Control,Drug$/m);
+    await dl.restore();
+  });
+
+  it('a stale/unset group field coerces to None (no Group row in the export)', async () => {
+    const dl = mockDownload();
+    renderModal({ groupField: 'ghost-field' });
+    await screen.findByLabelText('X axis (rows)');
+    await waitFor(() => expect(screen.getByText(/2 rows/i)).toBeInTheDocument());
+    fireEvent.click(screen.getByText('Export CSV'));
+    const text = await readBlobText(dl.getBlob());
+    expect(text).not.toMatch(/^Group,/m);
+    await dl.restore();
+  });
+});

frontend/tests/FileDropZone.test.jsx

@@ -0,0 +1,375 @@
+import React from 'react';
+import { render, screen, fireEvent, waitFor, act } from '@testing-library/react';
+import FileDropZone from '../src/components/FileDropZone';
+import { sessionFilesApi } from '../src/api/client';
+
+jest.mock('../src/api/client', () => ({
+  sessionFilesApi: {
+    list:   jest.fn(),
+    create: jest.fn(),
+    delete: jest.fn(),
+  },
+}));
+
+// ── Fixtures ───────────────────────────────────────────────────────────────────
+
+const DATE = '2026-04-23';
+
+const ANIMALS = [
+  { id: 'a1', animal_name: 'Rat 2852', animal_id_string: '2852' },
+  { id: 'a2', animal_name: 'Rat 3076', animal_id_string: '3076' },
+  { id: 'a3', animal_name: 'Rat 3077', animal_id_string: '3077' },
+];
+
+const STATUS_A1 = { id: 's-a1', animal_id: 'a1', date: `${DATE}T00:00:00.000Z` };
+const STATUS_A2 = { id: 's-a2', animal_id: 'a2', date: `${DATE}T00:00:00.000Z` };
+const STATUS_A3 = { id: 's-a3', animal_id: 'a3', date: `${DATE}T00:00:00.000Z` };
+
+const ROWS = [
+  { animal: ANIMALS[0], status: STATUS_A1 },
+  { animal: ANIMALS[1], status: STATUS_A2 },
+  { animal: ANIMALS[2], status: STATUS_A3 },
+];
+
+function makeFile(name, size = 1024, type = '') {
+  return new File(['x'], name, { type, lastModified: Date.now() });
+}
+
+function makeSavedFile(id, statusId, filename, fileSize = '10240') {
+  return { id, daily_status_id: statusId, filename, file_size: fileSize, file_type: 'CSV', last_modified: null, created_at: new Date().toISOString() };
+}
+
+function dropFiles(files) {
+  const zone = screen.getByTestId('drop-zone');
+  fireEvent.dragEnter(zone, { dataTransfer: { files } });
+  fireEvent.dragOver(zone, { dataTransfer: { files } });
+  fireEvent.drop(zone, { dataTransfer: { files } });
+}
+
+beforeEach(() => {
+  jest.clearAllMocks();
+  sessionFilesApi.list.mockResolvedValue([]);
+  sessionFilesApi.create.mockResolvedValue([]);
+  sessionFilesApi.delete.mockResolvedValue();
+});
+
+// ── Rendering ──────────────────────────────────────────────────────────────────
+
+describe('rendering', () => {
+  it('renders the drop zone', () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    expect(screen.getByTestId('drop-zone')).toBeInTheDocument();
+    expect(screen.getByText(/drag.*drop session files/i)).toBeInTheDocument();
+  });
+
+  it('shows naming convention hint using first animal id', () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    expect(screen.getByText(/2026-04-23_2852/)).toBeInTheDocument();
+  });
+
+  it('loads saved files on mount for each status', async () => {
+    sessionFilesApi.list.mockResolvedValue([]);
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    await waitFor(() => {
+      expect(sessionFilesApi.list).toHaveBeenCalledWith('s-a1');
+      expect(sessionFilesApi.list).toHaveBeenCalledWith('s-a2');
+      expect(sessionFilesApi.list).toHaveBeenCalledWith('s-a3');
+    });
+  });
+
+  it('shows saved files loaded from the API', async () => {
+    sessionFilesApi.list.mockImplementation((id) =>
+      id === 's-a1'
+        ? Promise.resolve([makeSavedFile('f1', 's-a1', `${DATE}_2852_trials.csv`)])
+        : Promise.resolve([])
+    );
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    await waitFor(() =>
+      expect(screen.getByText(`${DATE}_2852_trials.csv`)).toBeInTheDocument()
+    );
+    expect(screen.getByTestId('saved-files')).toBeInTheDocument();
+  });
+});
+
+// ── Drag state ─────────────────────────────────────────────────────────────────
+
+describe('drag interaction', () => {
+  it('highlights drop zone on dragenter', () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    const zone = screen.getByTestId('drop-zone');
+    fireEvent.dragEnter(zone, { dataTransfer: { files: [] } });
+    expect(zone.className).toMatch(/border-blue-400/);
+    expect(screen.getByText(/release to register/i)).toBeInTheDocument();
+  });
+
+  it('removes highlight on dragleave', () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    const zone = screen.getByTestId('drop-zone');
+    fireEvent.dragEnter(zone, { dataTransfer: { files: [] } });
+    fireEvent.dragLeave(zone, { dataTransfer: { files: [] } });
+    expect(zone.className).not.toMatch(/border-blue-400/);
+  });
+});
+
+// ── File matching ──────────────────────────────────────────────────────────────
+
+describe('filename-to-subject matching', () => {
+  it('matches files containing the animal_id_string to the correct subject', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([
+      makeFile(`${DATE}_2852_ephys_raw.bin`, 10_000_000_000),
+      makeFile(`${DATE}_3076_trials.csv`, 10_000_000),
+    ]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.getByText(/Rat 2852/)).toBeInTheDocument();
+    expect(screen.getByText(/Rat 3076/)).toBeInTheDocument();
+    expect(screen.getByText(`${DATE}_2852_ephys_raw.bin`)).toBeInTheDocument();
+    expect(screen.getByText(`${DATE}_3076_trials.csv`)).toBeInTheDocument();
+  });
+
+  it('shows unmatched section for files with no subject ID in name', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([makeFile('unknown_file.csv', 1024)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.getByText(/unmatched/i)).toBeInTheDocument();
+    expect(screen.getByText('unknown_file.csv')).toBeInTheDocument();
+  });
+
+  it('does not match a partial numeric overlap (2852 should not match 28520)', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([makeFile('session_28520_data.csv', 1024)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.getByText(/unmatched/i)).toBeInTheDocument();
+  });
+
+  // ── animal_name matching ───────────────────────────────────────────────────
+
+  it('matches by animal_name when the name appears literally in the filename', async () => {
+    const animal = { id: 'b1', animal_name: 'Homer', animal_id_string: null };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_Homer_session.csv`)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.queryByText(/unmatched/i)).not.toBeInTheDocument();
+    expect(screen.getByText(`${DATE}_Homer_session.csv`)).toBeInTheDocument();
+  });
+
+  it('matches multi-word animal_name with underscores as separator in filename', async () => {
+    const animal = { id: 'b1', animal_name: 'Rat A', animal_id_string: null };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_Rat_A_trials.csv`)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.queryByText(/unmatched/i)).not.toBeInTheDocument();
+  });
+
+  it('matches multi-word animal_name with dashes as separator in filename', async () => {
+    const animal = { id: 'b1', animal_name: 'Rat A', animal_id_string: null };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    dropFiles([makeFile(`${DATE}-Rat-A-session.bin`)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.queryByText(/unmatched/i)).not.toBeInTheDocument();
+  });
+
+  it('matches by animal_name even when animal_id_string is also set (OR logic)', async () => {
+    const animal = { id: 'b1', animal_name: 'Rat A', animal_id_string: '2852' };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    // File uses name, not ID
+    dropFiles([makeFile(`${DATE}_Rat_A_ephys.bin`)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.queryByText(/unmatched/i)).not.toBeInTheDocument();
+  });
+
+  it('does not match a partial name overlap (Rat should not match Rationale)', async () => {
+    const animal = { id: 'b1', animal_name: 'Rat', animal_id_string: null };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    dropFiles([makeFile('Rationale_study_data.csv')]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.getByText(/unmatched/i)).toBeInTheDocument();
+  });
+
+  it('shows warning for subjects with no matched files', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    // Only drop file for 2852 — 3076 and 3077 get no match
+    dropFiles([makeFile(`${DATE}_2852_trials.csv`, 1024)]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    expect(screen.getByText(/no files matched/i)).toBeInTheDocument();
+    expect(screen.getByText('3076')).toBeInTheDocument();
+    expect(screen.getByText('3077')).toBeInTheDocument();
+  });
+
+  it('matches all four files per subject correctly', async () => {
+    render(<FileDropZone rows={[{ animal: ANIMALS[0], status: STATUS_A1 }]} date={DATE} />);
+    dropFiles([
+      makeFile(`${DATE}_2852_ephys_raw.bin`,    10_000_000_000),
+      makeFile(`${DATE}_2852_kilosort.h5`,       10_000_000_000),
+      makeFile(`${DATE}_2852_trials.csv`,            10_000_000),
+      makeFile(`${DATE}_2852_behavior_log.csv`,       10_000_000),
+    ]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    // Save button label is the authoritative "all 4 matched" signal
+    expect(screen.getByTestId('save-btn')).toHaveTextContent('Register 4 files');
+  });
+
+  it('handles multiple subjects with 4 files each simultaneously', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([
+      makeFile(`${DATE}_2852_ephys_raw.bin`,    10_000_000_000),
+      makeFile(`${DATE}_2852_kilosort.h5`,       10_000_000_000),
+      makeFile(`${DATE}_2852_trials.csv`,            10_000_000),
+      makeFile(`${DATE}_2852_behavior_log.csv`,       10_000_000),
+      makeFile(`${DATE}_3076_ephys_raw.bin`,    10_000_000_000),
+      makeFile(`${DATE}_3076_kilosort.h5`,       10_000_000_000),
+      makeFile(`${DATE}_3076_trials.csv`,            10_000_000),
+      makeFile(`${DATE}_3076_behavior_log.csv`,       10_000_000),
+    ]);
+    await waitFor(() => screen.getByTestId('drop-preview'));
+    const saveBtn = screen.getByTestId('save-btn');
+    expect(saveBtn.textContent).toMatch(/8 files/);
+  });
+});
+
+// ── Remove before saving ───────────────────────────────────────────────────────
+
+describe('remove files before saving', () => {
+  it('removes a matched file when ✕ is clicked', async () => {
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_2852_trials.csv`, 1024)]);
+    await waitFor(() => screen.getByText(`${DATE}_2852_trials.csv`));
+    fireEvent.click(screen.getAllByText('✕')[0]);
+    await waitFor(() =>
+      expect(screen.queryByText(`${DATE}_2852_trials.csv`)).not.toBeInTheDocument()
+    );
+  });
+});
+
+// ── Saving ─────────────────────────────────────────────────────────────────────
+
+describe('saving metadata', () => {
+  it('calls sessionFilesApi.create with correct payload including matching metadata', async () => {
+    const file = makeFile(`${DATE}_2852_trials.csv`);
+    const savedFile = makeSavedFile('f1', 's-a1', file.name, String(file.size));
+    sessionFilesApi.create.mockResolvedValue([savedFile]);
+
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([file]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+
+    await waitFor(() =>
+      expect(sessionFilesApi.create).toHaveBeenCalledWith(
+        's-a1',
+        expect.arrayContaining([
+          expect.objectContaining({
+            filename:              `${DATE}_2852_trials.csv`,
+            file_size:             file.size,
+            file_type:             'CSV',
+            matched_identifier:    '2852',
+            animal_id_string_snap: '2852',
+            animal_name_snap:      'Rat 2852',
+          }),
+        ])
+      )
+    );
+  });
+
+  it('sets matched_identifier to animal_name when file matched by name', async () => {
+    const animal = { id: 'b1', animal_name: 'Rat A', animal_id_string: null };
+    const row    = { animal, status: { id: 's-b1', animal_id: 'b1', date: `${DATE}T00:00:00.000Z` } };
+    sessionFilesApi.create.mockResolvedValue([]);
+    render(<FileDropZone rows={[row]} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_Rat_A_trials.csv`)]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+    await waitFor(() =>
+      expect(sessionFilesApi.create).toHaveBeenCalledWith(
+        's-b1',
+        expect.arrayContaining([
+          expect.objectContaining({
+            matched_identifier:    'Rat A',
+            animal_id_string_snap: null,
+            animal_name_snap:      'Rat A',
+          }),
+        ])
+      )
+    );
+  });
+
+  it('does not call create for subjects with no matched files', async () => {
+    sessionFilesApi.create.mockResolvedValue([]);
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    // Only 2852 gets a file
+    dropFiles([makeFile(`${DATE}_2852_trials.csv`, 1024)]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+
+    await waitFor(() => expect(sessionFilesApi.create).toHaveBeenCalledTimes(1));
+    expect(sessionFilesApi.create).toHaveBeenCalledWith('s-a1', expect.any(Array));
+  });
+
+  it('stores correct file_type classification from extension', async () => {
+    sessionFilesApi.create.mockResolvedValue([]);
+    render(<FileDropZone rows={[{ animal: ANIMALS[0], status: STATUS_A1 }]} date={DATE} />);
+    dropFiles([
+      makeFile(`${DATE}_2852_ephys.bin`,  10_000_000_000),
+      makeFile(`${DATE}_2852_spikes.h5`,  10_000_000_000),
+      makeFile(`${DATE}_2852_trials.csv`,     10_000_000),
+      makeFile(`${DATE}_2852_log.csv`,        10_000_000),
+    ]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+
+    await waitFor(() => expect(sessionFilesApi.create).toHaveBeenCalled());
+    const [, files] = sessionFilesApi.create.mock.calls[0];
+    expect(files.find((f) => f.filename.endsWith('.bin')).file_type).toBe('Binary');
+    expect(files.find((f) => f.filename.endsWith('.h5')).file_type).toBe('HDF5');
+    expect(files.filter((f) => f.filename.endsWith('.csv'))).toHaveLength(2);
+    files.filter((f) => f.filename.endsWith('.csv')).forEach((f) => {
+      expect(f.file_type).toBe('CSV');
+    });
+  });
+
+  it('clears the drop preview after a successful save', async () => {
+    sessionFilesApi.create.mockResolvedValue([makeSavedFile('f1', 's-a1', `${DATE}_2852_trials.csv`)]);
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_2852_trials.csv`, 1024)]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+    await waitFor(() =>
+      expect(screen.queryByTestId('drop-preview')).not.toBeInTheDocument()
+    );
+  });
+
+  it('shows an error message when create fails', async () => {
+    sessionFilesApi.create.mockRejectedValue({ message: 'Server error' });
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    dropFiles([makeFile(`${DATE}_2852_trials.csv`, 1024)]);
+    await waitFor(() => screen.getByTestId('save-btn'));
+    fireEvent.click(screen.getByTestId('save-btn'));
+    await waitFor(() => screen.getByText(/server error/i));
+  });
+});
+
+// ── Deleting saved files ───────────────────────────────────────────────────────
+
+describe('deleting saved files', () => {
+  it('removes a saved file when its ✕ is clicked', async () => {
+    sessionFilesApi.list.mockImplementation((id) =>
+      id === 's-a1'
+        ? Promise.resolve([makeSavedFile('f1', 's-a1', `${DATE}_2852_trials.csv`)])
+        : Promise.resolve([])
+    );
+    render(<FileDropZone rows={ROWS} date={DATE} />);
+    await waitFor(() => screen.getByText(`${DATE}_2852_trials.csv`));
+    fireEvent.click(screen.getAllByText('✕')[0]);
+    await waitFor(() =>
+      expect(sessionFilesApi.delete).toHaveBeenCalledWith('f1')
+    );
+    await waitFor(() =>
+      expect(screen.queryByText(`${DATE}_2852_trials.csv`)).not.toBeInTheDocument()
+    );
+  });
+});

frontend/tests/Modal.test.jsx

@@ -0,0 +1,31 @@
+import React from 'react';
+import { render, screen, fireEvent } from '@testing-library/react';
+import Modal from '../src/components/ui/Modal';
+
+describe('Modal component', () => {
+  it('does not render when isOpen is false', () => {
+    render(<Modal isOpen={false} onClose={() => {}} title="Test"><p>content</p></Modal>);
+    expect(screen.queryByRole('dialog')).not.toBeInTheDocument();
+  });
+
+  it('renders title and children when open', () => {
+    render(<Modal isOpen={true} onClose={() => {}} title="My Modal"><p>Hello</p></Modal>);
+    expect(screen.getByRole('dialog')).toBeInTheDocument();
+    expect(screen.getByText('My Modal')).toBeInTheDocument();
+    expect(screen.getByText('Hello')).toBeInTheDocument();
+  });
+
+  it('calls onClose when close button is clicked', () => {
+    const onClose = jest.fn();
+    render(<Modal isOpen={true} onClose={onClose} title="T"><p>x</p></Modal>);
+    fireEvent.click(screen.getByLabelText(/close modal/i));
+    expect(onClose).toHaveBeenCalled();
+  });
+
+  it('calls onClose when Escape key is pressed', () => {
+    const onClose = jest.fn();
+    render(<Modal isOpen={true} onClose={onClose} title="T"><p>x</p></Modal>);
+    fireEvent.keyDown(document, { key: 'Escape' });
+    expect(onClose).toHaveBeenCalled();
+  });
+});

frontend/tests/SubjectSidebar.test.jsx

@@ -0,0 +1,104 @@
+import React from 'react';
+import { render, screen, fireEvent, within } from '@testing-library/react';
+import { SubjectSidebar } from '../src/components/SubjectSidebar';
+
+const LINES = [
+  { id: 'a1', name: 'Mouse-A1', group: 'Group A', color: '#111' },
+  { id: 'a2', name: 'Mouse-A2', group: 'Group A', color: '#222' },
+  { id: 'b1', name: 'Mouse-B1', group: 'Group B', color: '#333' },
+];
+
+function setup(overrides = {}) {
+  const props = {
+    lines: LINES,
+    hiddenSubjects: new Set(),
+    onToggleSubject: jest.fn(),
+    onToggleGroup: jest.fn(),
+    onShowAll: jest.fn(),
+    onHighlight: jest.fn(),
+    ...overrides,
+  };
+  render(<SubjectSidebar {...props} />);
+  return props;
+}
+
+it('renders each group header with its subject count', () => {
+  setup();
+  expect(screen.getByText('Group A')).toBeInTheDocument();
+  expect(screen.getByText('Group B')).toBeInTheDocument();
+  expect(screen.getByText('(2)')).toBeInTheDocument();
+  expect(screen.getByText('(1)')).toBeInTheDocument();
+});
+
+it('renders a subject checkbox per subject, checked when visible', () => {
+  setup({ hiddenSubjects: new Set(['a2']) });
+  expect(screen.getByLabelText('Mouse-A1').checked).toBe(true);
+  expect(screen.getByLabelText('Mouse-A2').checked).toBe(false);
+});
+
+it('calls onToggleSubject with the id when a subject checkbox is clicked', () => {
+  const { onToggleSubject } = setup();
+  fireEvent.click(screen.getByLabelText('Mouse-A1'));
+  expect(onToggleSubject).toHaveBeenCalledWith('a1');
+});
+
+it('shows the group checkbox as indeterminate when the group is mixed', () => {
+  setup({ hiddenSubjects: new Set(['a1']) });
+  const groupCheckbox = screen.getByLabelText(/Group A/);
+  expect(groupCheckbox.indeterminate).toBe(true);
+  expect(groupCheckbox.checked).toBe(false);
+});
+
+it('checks the group checkbox when all members are visible', () => {
+  setup();
+  expect(screen.getByLabelText(/Group A/).checked).toBe(true);
+});
+
+it('calls onToggleGroup with the group ids and hidden=true when an all-visible group is clicked', () => {
+  const { onToggleGroup } = setup();
+  fireEvent.click(screen.getByLabelText(/Group A/));
+  expect(onToggleGroup).toHaveBeenCalledWith(['a1', 'a2'], true);
+});
+
+it('shows the group checkbox unchecked and not indeterminate when all members are hidden', () => {
+  setup({ hiddenSubjects: new Set(['a1', 'a2']) });
+  const groupCheckbox = screen.getByLabelText(/Group A/);
+  expect(groupCheckbox.checked).toBe(false);
+  expect(groupCheckbox.indeterminate).toBe(false);
+});
+
+it('calls onToggleGroup with hidden=false when a fully-hidden group is clicked', () => {
+  const { onToggleGroup } = setup({ hiddenSubjects: new Set(['a1', 'a2']) });
+  fireEvent.click(screen.getByLabelText(/Group A/));
+  expect(onToggleGroup).toHaveBeenCalledWith(['a1', 'a2'], false);
+});
+
+it('hides the Show all link when nothing is hidden, shows it otherwise', () => {
+  const { rerender } = render(
+    <SubjectSidebar lines={LINES} hiddenSubjects={new Set()}
+      onToggleSubject={() => {}} onToggleGroup={() => {}}
+      onShowAll={() => {}} onHighlight={() => {}} />,
+  );
+  expect(screen.queryByText('Show all')).toBeNull();
+  rerender(
+    <SubjectSidebar lines={LINES} hiddenSubjects={new Set(['a1'])}
+      onToggleSubject={() => {}} onToggleGroup={() => {}}
+      onShowAll={() => {}} onHighlight={() => {}} />,
+  );
+  expect(screen.getByText('Show all')).toBeInTheDocument();
+});
+
+it('calls onShowAll when the Show all link is clicked', () => {
+  const { onShowAll } = setup({ hiddenSubjects: new Set(['a1']) });
+  fireEvent.click(screen.getByText('Show all'));
+  expect(onShowAll).toHaveBeenCalled();
+});
+
+it('calls onHighlight on subject row hover enter/leave', () => {
+  const { onHighlight } = setup();
+  const row = screen.getByLabelText('Mouse-A1').closest('label');
+  fireEvent.mouseEnter(row);
+  expect(onHighlight).toHaveBeenCalledWith('a1');
+  fireEvent.mouseLeave(row);
+  expect(onHighlight).toHaveBeenCalledWith(null);
+});

frontend/tests/crossSubjectChart.test.js

@@ -0,0 +1,150 @@
+import {
+  sortPayloadByValueDesc,
+  toggleInSet,
+  setIdsHidden,
+  groupVisibilityState,
+  groupLines,
+  serializePlotConfig,
+  readPlotConfig,
+} from '../src/lib/crossSubjectChart';
+
+describe('sortPayloadByValueDesc', () => {
+  it('sorts by value descending and drops null/undefined values', () => {
+    const payload = [
+      { dataKey: 'a', value: 40 },
+      { dataKey: 'b', value: null },
+      { dataKey: 'c', value: 92 },
+      { dataKey: 'd', value: 78 },
+    ];
+    expect(sortPayloadByValueDesc(payload).map((p) => p.dataKey)).toEqual(['c', 'd', 'a']);
+  });
+  it('returns [] for non-array input', () => {
+    expect(sortPayloadByValueDesc(undefined)).toEqual([]);
+  });
+  it('does not mutate the input array', () => {
+    const payload = [{ dataKey: 'a', value: 1 }, { dataKey: 'b', value: 2 }];
+    sortPayloadByValueDesc(payload);
+    expect(payload.map((p) => p.dataKey)).toEqual(['a', 'b']);
+  });
+});
+
+describe('toggleInSet', () => {
+  it('adds a missing id and removes a present id, returning a new Set', () => {
+    const a = new Set(['x']);
+    const added = toggleInSet(a, 'y');
+    expect([...added].sort()).toEqual(['x', 'y']);
+    expect(added).not.toBe(a);
+    const removed = toggleInSet(added, 'x');
+    expect([...removed]).toEqual(['y']);
+  });
+});
+
+describe('setIdsHidden', () => {
+  it('adds all ids when hidden=true', () => {
+    expect([...setIdsHidden(new Set(['a']), ['b', 'c'], true)].sort()).toEqual(['a', 'b', 'c']);
+  });
+  it('removes all ids when hidden=false', () => {
+    expect([...setIdsHidden(new Set(['a', 'b', 'c']), ['b', 'c'], false)]).toEqual(['a']);
+  });
+  it('returns a new Set', () => {
+    const s = new Set();
+    expect(setIdsHidden(s, ['a'], true)).not.toBe(s);
+  });
+});
+
+describe('groupVisibilityState', () => {
+  it("returns 'all' when none of the ids are hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set())).toBe('all');
+  });
+  it("returns 'none' when all ids are hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set(['a', 'b']))).toBe('none');
+  });
+  it("returns 'some' when a subset is hidden", () => {
+    expect(groupVisibilityState(['a', 'b'], new Set(['a']))).toBe('some');
+  });
+  it("returns 'none' for an empty group", () => {
+    expect(groupVisibilityState([], new Set())).toBe('none');
+  });
+});
+
+describe('groupLines', () => {
+  it('groups by .group preserving first-seen group order and within-group order', () => {
+    const lines = [
+      { id: '1', group: 'B' },
+      { id: '2', group: 'A' },
+      { id: '3', group: 'B' },
+    ];
+    const out = groupLines(lines);
+    expect(out.map((g) => g.group)).toEqual(['B', 'A']);
+    expect(out[0].subjects.map((s) => s.id)).toEqual(['1', '3']);
+  });
+  it("uses '—' for lines with no group", () => {
+    expect(groupLines([{ id: '1' }])[0].group).toBe('—');
+  });
+});
+
+describe('serializePlotConfig', () => {
+  const STATE = {
+    xField: '__days__', groupBy: 'g1', tickStep: 2, metric: 'Success',
+    hiddenSubjects: new Set(['b', 'a']), sidebarOpen: true,
+    counts: { height: 220, yMin: '0', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: 'f2' },
+    rate:   { height: 160, yMin: '', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: null },
+  };
+
+  it('produces a plain JSON object with hiddenSubjects as a sorted array', () => {
+    const out = serializePlotConfig(STATE);
+    expect(out.hiddenSubjects).toEqual(['a', 'b']);
+    expect(out.sidebarOpen).toBe(true);
+    expect(out.xField).toBe('__days__');
+    expect(out.metric).toBe('Success');
+    expect(out.counts).toEqual({ height: 220, yMin: '0', yMax: '', xZoomMin: '', xZoomMax: '', xFieldOverride: 'f2' });
+    expect(out.rate.xFieldOverride).toBeNull();
+  });
+
+  it('round-trips through readPlotConfig (values preserved)', () => {
+    const back = readPlotConfig(serializePlotConfig(STATE));
+    expect(back.xField).toBe('__days__');
+    expect(back.groupBy).toBe('g1');
+    expect(back.tickStep).toBe(2);
+    expect(back.hiddenSubjects).toEqual(['a', 'b']);
+    expect(back.sidebarOpen).toBe(true);
+    expect(back.counts.height).toBe(220);
+    expect(back.counts.xFieldOverride).toBe('f2');
+    expect(back.rate.height).toBe(160);
+    expect(back.rate.xFieldOverride).toBeNull();
+  });
+
+  it('returns an empty hiddenSubjects array when state.hiddenSubjects is null', () => {
+    expect(serializePlotConfig({ ...STATE, hiddenSubjects: null }).hiddenSubjects).toEqual([]);
+  });
+});
+
+describe('readPlotConfig', () => {
+  it('returns safe defaults for null', () => {
+    const c = readPlotConfig(null);
+    expect(c.hiddenSubjects).toEqual([]);
+    expect(c.sidebarOpen).toBe(false);
+    expect(c.xField).toBeUndefined();
+    expect(c.counts.yMin).toBe('');
+    expect(c.counts.xFieldOverride).toBeNull();
+  });
+
+  it('returns safe defaults for a non-object', () => {
+    expect(readPlotConfig([1, 2]).hiddenSubjects).toEqual([]);
+    expect(readPlotConfig('nope').sidebarOpen).toBe(false);
+  });
+
+  it('filters non-string hiddenSubjects and ignores wrong-typed fields', () => {
+    const c = readPlotConfig({ hiddenSubjects: ['a', 5, 'b'], tickStep: 'x', sidebarOpen: 'yes' });
+    expect(c.hiddenSubjects).toEqual(['a', 'b']);
+    expect(c.tickStep).toBeUndefined();
+    expect(c.sidebarOpen).toBe(false);
+  });
+
+  it('does not throw on malformed nested chart settings', () => {
+    expect(() => readPlotConfig({ counts: 'bad', rate: [] })).not.toThrow();
+    const c = readPlotConfig({ counts: 'bad' });
+    expect(c.counts.yMin).toBe('');
+    expect(c.counts.height).toBeUndefined();
+  });
+});

frontend/tests/csvAnalysis.test.js

@@ -0,0 +1,361 @@
+import {
+  parseCSVHeaders,
+  parseCSV,
+  getUniqueNoteValues,
+  runAnalysis,
+  extractNumber,
+  computeNumericSeries,
+} from '../src/lib/csvAnalysis';
+
+// ── Fixtures ───────────────────────────────────────────────────────────────────
+
+// Minimal CSV mimicking the real experiment file structure
+const FIXTURE_CSV = `timestamp,frame_number,frame_line_status,note
+0.0,1,10,
+1.0,2,10,f
+2.0,3,10,s
+3.0,4,10,s
+4.0,5,10,f
+5.0,6,10,
+6.0,7,10,s
+7.0,8,10,f
+8.0,9,10,f
+9.0,10,10,s`;
+
+// Same data but with Windows-style line endings
+const FIXTURE_CSV_CRLF = FIXTURE_CSV.replace(/\n/g, '\r\n');
+
+// CSV with quoted field containing a comma
+const FIXTURE_CSV_QUOTED = `timestamp,note\n1.0,"hello, world"\n2.0,plain`;
+
+// Out-of-order timestamps (should be sorted)
+const FIXTURE_UNSORTED = `timestamp,note
+3.0,s
+1.0,f
+2.0,s`;
+
+const CLASSIFICATIONS = { f: 'Failure', s: 'Success' };
+
+// ── parseCSVHeaders ────────────────────────────────────────────────────────────
+
+describe('parseCSVHeaders', () => {
+  test('returns column names from first line', () => {
+    expect(parseCSVHeaders(FIXTURE_CSV)).toEqual([
+      'timestamp', 'frame_number', 'frame_line_status', 'note',
+    ]);
+  });
+
+  test('handles CRLF line endings', () => {
+    expect(parseCSVHeaders(FIXTURE_CSV_CRLF)).toEqual([
+      'timestamp', 'frame_number', 'frame_line_status', 'note',
+    ]);
+  });
+
+  test('handles single-line CSV (no newline)', () => {
+    expect(parseCSVHeaders('a,b,c')).toEqual(['a', 'b', 'c']);
+  });
+});
+
+// ── parseCSV ──────────────────────────────────────────────────────────────────
+
+describe('parseCSV', () => {
+  test('returns headers and rows', () => {
+    const { headers, rows } = parseCSV(FIXTURE_CSV);
+    expect(headers).toEqual(['timestamp', 'frame_number', 'frame_line_status', 'note']);
+    expect(rows).toHaveLength(10);
+  });
+
+  test('row values are keyed by header name', () => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    expect(rows[0]).toEqual({ timestamp: '0.0', frame_number: '1', frame_line_status: '10', note: '' });
+    expect(rows[1]).toEqual({ timestamp: '1.0', frame_number: '2', frame_line_status: '10', note: 'f' });
+  });
+
+  test('handles CRLF line endings', () => {
+    const { rows } = parseCSV(FIXTURE_CSV_CRLF);
+    expect(rows).toHaveLength(10);
+    expect(rows[1].note).toBe('f');
+  });
+
+  test('handles quoted fields containing commas', () => {
+    const { rows } = parseCSV(FIXTURE_CSV_QUOTED);
+    expect(rows[0].note).toBe('hello, world');
+    expect(rows[1].note).toBe('plain');
+  });
+
+  test('skips blank lines', () => {
+    const csv = 'a,b\n1,2\n\n3,4\n';
+    const { rows } = parseCSV(csv);
+    expect(rows).toHaveLength(2);
+  });
+});
+
+// ── getUniqueNoteValues ────────────────────────────────────────────────────────
+
+describe('getUniqueNoteValues', () => {
+  test('returns sorted unique non-empty values', () => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    expect(getUniqueNoteValues(rows, 'note')).toEqual(['f', 's']);
+  });
+
+  test('ignores empty strings', () => {
+    const rows = [{ note: '' }, { note: 'a' }, { note: '' }, { note: 'b' }];
+    expect(getUniqueNoteValues(rows, 'note')).toEqual(['a', 'b']);
+  });
+
+  test('trims whitespace before deduplication', () => {
+    const rows = [{ note: ' a ' }, { note: 'a' }, { note: 'b' }];
+    expect(getUniqueNoteValues(rows, 'note')).toEqual(['a', 'b']);
+  });
+
+  test('returns empty array when no non-empty notes', () => {
+    const rows = [{ note: '' }, { note: '' }];
+    expect(getUniqueNoteValues(rows, 'note')).toEqual([]);
+  });
+});
+
+// ── runAnalysis ────────────────────────────────────────────────────────────────
+
+describe('runAnalysis', () => {
+  let result;
+
+  beforeEach(() => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    result = runAnalysis(rows, 'timestamp', 'note', CLASSIFICATIONS);
+  });
+
+  // Fixture note sequence (sorted by timestamp, empty rows excluded):
+  // t=1 f, t=2 s, t=3 s, t=4 f, t=6 s, t=7 f, t=8 f, t=9 s
+  // Categories: F S S F S F F S
+
+  test('totalNoteRows counts only rows with non-empty note', () => {
+    expect(result.totalNoteRows).toBe(8);
+  });
+
+  test('sequence preserves order and maps to categories', () => {
+    const notes = result.sequence.map(r => r.note);
+    expect(notes).toEqual(['f', 's', 's', 'f', 's', 'f', 'f', 's']);
+
+    const cats = result.sequence.map(r => r.category);
+    expect(cats).toEqual(['Failure', 'Success', 'Success', 'Failure', 'Success', 'Failure', 'Failure', 'Success']);
+  });
+
+  test('categoryCounts totals are correct', () => {
+    expect(result.categoryCounts['Failure'].total).toBe(4);
+    expect(result.categoryCounts['Success'].total).toBe(4);
+  });
+
+  test('categoryCounts byNote breakdown is correct', () => {
+    expect(result.categoryCounts['Failure'].byNote).toEqual({ f: 4 });
+    expect(result.categoryCounts['Success'].byNote).toEqual({ s: 4 });
+  });
+
+  test('runs (run-length encoding) are correct', () => {
+    // F S S F S F F S  →  F×1, S×2, F×1, S×1, F×2, S×1
+    expect(result.runs).toEqual([
+      { category: 'Failure', length: 1 },
+      { category: 'Success', length: 2 },
+      { category: 'Failure', length: 1 },
+      { category: 'Success', length: 1 },
+      { category: 'Failure', length: 2 },
+      { category: 'Success', length: 1 },
+    ]);
+  });
+
+  test('consecutiveStats totalRuns', () => {
+    expect(result.consecutiveStats['Failure'].totalRuns).toBe(3);
+    expect(result.consecutiveStats['Success'].totalRuns).toBe(3);
+  });
+
+  test('consecutiveStats maxRun', () => {
+    expect(result.consecutiveStats['Failure'].maxRun).toBe(2);
+    expect(result.consecutiveStats['Success'].maxRun).toBe(2);
+  });
+
+  test('consecutiveStats avgRun', () => {
+    // Failure runs: [1,1,2] → avg = 4/3
+    expect(result.consecutiveStats['Failure'].avgRun).toBeCloseTo(4 / 3);
+    // Success runs: [2,1,1] → avg = 4/3
+    expect(result.consecutiveStats['Success'].avgRun).toBeCloseTo(4 / 3);
+  });
+
+  test('consecutiveStats runLengths array', () => {
+    expect(result.consecutiveStats['Failure'].runLengths).toEqual([1, 1, 2]);
+    expect(result.consecutiveStats['Success'].runLengths).toEqual([2, 1, 1]);
+  });
+});
+
+describe('runAnalysis — sorting', () => {
+  test('sorts rows by timestamp before building sequence', () => {
+    const { rows } = parseCSV(FIXTURE_UNSORTED);
+    // Input order: s(3), f(1), s(2) — sorted order: f(1), s(2), s(3)
+    const result = runAnalysis(rows, 'timestamp', 'note', CLASSIFICATIONS);
+    expect(result.sequence.map(r => r.note)).toEqual(['f', 's', 's']);
+  });
+});
+
+describe('runAnalysis — unclassified notes', () => {
+  test('unclassified notes appear in sequence with null category', () => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    // Only classify 'f'; leave 's' unclassified
+    const result = runAnalysis(rows, 'timestamp', 'note', { f: 'Failure' });
+    const nullCats = result.sequence.filter(r => r.category === null);
+    expect(nullCats.length).toBe(4); // 4 's' notes
+  });
+
+  test('unclassified notes are excluded from categoryCounts', () => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    const result = runAnalysis(rows, 'timestamp', 'note', { f: 'Failure' });
+    expect(result.categoryCounts['Success']).toBeUndefined();
+  });
+
+  test('unclassified notes do not break or extend runs', () => {
+    // Sequence with 'x' unclassified: f x f → should still be one Failure run of 2
+    const csv = 'ts,note\n1.0,f\n2.0,x\n3.0,f';
+    const { rows } = parseCSV(csv);
+    // 'x' is unclassified, 'f' → Failure
+    // After skipping 'x': f, f → one run of Failure×2
+    const result = runAnalysis(rows, 'ts', 'note', { f: 'Failure' });
+    expect(result.runs).toEqual([{ category: 'Failure', length: 2 }]);
+  });
+});
+
+describe('runAnalysis — multiple note values per category', () => {
+  test('groups multiple note values under one category', () => {
+    // The user's example: ss and s both belong to Success
+    const csv = 'ts,note\n1.0,ss\n2.0,s\n3.0,s';
+    const { rows } = parseCSV(csv);
+    const result = runAnalysis(rows, 'ts', 'note', { ss: 'Success', s: 'Success' });
+    expect(result.categoryCounts['Success'].total).toBe(3);
+    expect(result.categoryCounts['Success'].byNote).toEqual({ ss: 1, s: 2 });
+  });
+
+  test('run-length encoding with multiple note values in same category', () => {
+    const csv = 'ts,note\n1.0,ss\n2.0,s\n3.0,f';
+    const { rows } = parseCSV(csv);
+    const result = runAnalysis(rows, 'ts', 'note', { ss: 'Success', s: 'Success', f: 'Failure' });
+    // ss and s are both Success → run of 2, then Failure run of 1
+    expect(result.runs).toEqual([
+      { category: 'Success', length: 2 },
+      { category: 'Failure', length: 1 },
+    ]);
+  });
+});
+
+describe('runAnalysis — edge cases', () => {
+  test('empty rows returns zero totals', () => {
+    const result = runAnalysis([], 'timestamp', 'note', CLASSIFICATIONS);
+    expect(result.totalNoteRows).toBe(0);
+    expect(result.sequence).toEqual([]);
+    expect(result.runs).toEqual([]);
+    expect(result.categoryCounts).toEqual({});
+    expect(result.consecutiveStats).toEqual({});
+  });
+
+  test('all notes unclassified', () => {
+    const { rows } = parseCSV(FIXTURE_CSV);
+    const result = runAnalysis(rows, 'timestamp', 'note', {});
+    expect(result.categoryCounts).toEqual({});
+    expect(result.runs).toEqual([]);
+  });
+
+  test('single note row', () => {
+    const csv = 'ts,note\n1.0,f';
+    const { rows } = parseCSV(csv);
+    const result = runAnalysis(rows, 'ts', 'note', { f: 'Failure' });
+    expect(result.totalNoteRows).toBe(1);
+    expect(result.runs).toEqual([{ category: 'Failure', length: 1 }]);
+    expect(result.consecutiveStats['Failure'].maxRun).toBe(1);
+    expect(result.consecutiveStats['Failure'].avgRun).toBe(1);
+  });
+
+  test('all same category', () => {
+    const csv = 'ts,note\n1.0,f\n2.0,f\n3.0,f';
+    const { rows } = parseCSV(csv);
+    const result = runAnalysis(rows, 'ts', 'note', { f: 'Failure' });
+    expect(result.runs).toEqual([{ category: 'Failure', length: 3 }]);
+    expect(result.consecutiveStats['Failure'].maxRun).toBe(3);
+    expect(result.consecutiveStats['Failure'].totalRuns).toBe(1);
+  });
+});
+
+describe('extractNumber', () => {
+  test('extracts positive decimal from prefixed string', () => {
+    expect(extractNumber('L25.5')).toBe(25.5);
+  });
+  test('extracts negative integer with letter prefix', () => {
+    expect(extractNumber('R-12')).toBe(-12);
+  });
+  test('extracts integer from underscore-separated label', () => {
+    expect(extractNumber('trial_007')).toBe(7);
+  });
+  test('does not parse scientific notation as one number', () => {
+    // Accepted limitation: regex matches "3.2", strips "e2"
+    expect(extractNumber('3.2e2')).toBe(3.2);
+  });
+  test('strips trailing units', () => {
+    expect(extractNumber('42 ms')).toBe(42);
+  });
+  test('returns null for purely alphabetic string', () => {
+    expect(extractNumber('abc')).toBeNull();
+  });
+  test('returns null for empty string', () => {
+    expect(extractNumber('')).toBeNull();
+  });
+  test('returns null for null/undefined', () => {
+    expect(extractNumber(null)).toBeNull();
+    expect(extractNumber(undefined)).toBeNull();
+  });
+});
+
+describe('computeNumericSeries', () => {
+  const rows = [
+    { frame: '1', timestamp: '0.0', note: 'L25' },
+    { frame: '3', timestamp: '2.0', note: 'L30.5' },
+    { frame: '2', timestamp: '1.0', note: 'L40' },
+    { frame: '4', timestamp: '3.0', note: 'F' },
+    { frame: '5', timestamp: '4.0', note: 'abc' },   // bucket-member but no number
+    { frame: 'x', timestamp: '5.0', note: 'L99' },   // bad x
+    { frame: '6', timestamp: '6.0', note: '' },      // not in bucket
+  ];
+  const bucket = { name: 'Lick latency', type: 'numerical', notes: ['L25', 'L30.5', 'L40', 'abc', 'L99'] };
+
+  test('returns sorted points with average and counts', () => {
+    const out = computeNumericSeries(rows, 'frame', 'note', bucket);
+    expect(out.points).toEqual([
+      { x: 1, value: 25,   raw: 'L25' },
+      { x: 2, value: 40,   raw: 'L40' },
+      { x: 3, value: 30.5, raw: 'L30.5' },
+    ]);
+    expect(out.avg).toBeCloseTo((25 + 40 + 30.5) / 3);
+    expect(out.skipped).toBe(2);   // 'abc' (no number) + bad x
+    expect(out.total).toBe(5);     // bucket-member rows
+    expect(out.xLabel).toBe('frame');
+  });
+
+  test('falls back to timestamp x-column when frame is empty string', () => {
+    const out = computeNumericSeries(rows, 'timestamp', 'note', bucket);
+    expect(out.xLabel).toBe('timestamp');
+    expect(out.points[0].x).toBe(0);
+  });
+
+  test('returns avg=null and empty points when nothing plottable', () => {
+    const onlyBad = [
+      { frame: '1', note: 'abc' },
+    ];
+    const b = { name: 'Z', type: 'numerical', notes: ['abc'] };
+    const out = computeNumericSeries(onlyBad, 'frame', 'note', b);
+    expect(out.points).toEqual([]);
+    expect(out.avg).toBeNull();
+    expect(out.skipped).toBe(1);
+    expect(out.total).toBe(1);
+  });
+
+  test('returns total=0 when bucket notes match nothing in rows', () => {
+    const b = { name: 'Empty', type: 'numerical', notes: ['nope'] };
+    const out = computeNumericSeries(rows, 'frame', 'note', b);
+    expect(out.total).toBe(0);
+    expect(out.points).toEqual([]);
+    expect(out.avg).toBeNull();
+  });
+});

frontend/tests/dataExport.test.js

@@ -0,0 +1,308 @@
+import { extractValue } from '../src/lib/dataExport';
+import { listExportableParams } from '../src/lib/dataExport';
+
+const status = {
+  vitals: 'ok',
+  custom_fields: { 'f-weight': 250 },
+  analysis_summary: { total: 12, success_rate: 0.83, counts: { Success: 10, Failure: 2 } },
+};
+
+describe('extractValue', () => {
+  it('reads a builtin field via statusKey', () => {
+    expect(extractValue(status, { kind: 'builtin', statusKey: 'vitals' })).toBe('ok');
+  });
+  it('reads a custom field via fieldId', () => {
+    expect(extractValue(status, { kind: 'custom', fieldId: 'f-weight' })).toBe(250);
+  });
+  it('reads session-metric total', () => {
+    expect(extractValue(status, { kind: 'total' })).toBe(12);
+  });
+  it('reads session-metric success_rate as a raw 0-1 fraction', () => {
+    expect(extractValue(status, { kind: 'success_rate' })).toBe(0.83);
+  });
+  it('reads a dynamic count category', () => {
+    expect(extractValue(status, { kind: 'category', category: 'Failure' })).toBe(2);
+  });
+  it('returns null when analysis_summary is absent', () => {
+    expect(extractValue({ custom_fields: {} }, { kind: 'total' })).toBeNull();
+    expect(extractValue({}, { kind: 'category', category: 'Success' })).toBeNull();
+  });
+  it('returns null for a missing custom field', () => {
+    expect(extractValue({ custom_fields: {} }, { kind: 'custom', fieldId: 'nope' })).toBeNull();
+    expect(extractValue({}, { kind: 'builtin', statusKey: 'notes' })).toBeNull();
+  });
+});
+
+const dailyTemplate = [
+  { fieldId: 'b-vitals', key: 'vitals', label: 'Vitals', builtin: true, active: true },
+  { fieldId: 'c-weight', key: 'weight', label: 'Weight (g)', builtin: false, active: false },
+];
+const statuses = [
+  { analysis_summary: { counts: { Success: 1, Failure: 0 } } },
+  { analysis_summary: { counts: { Success: 2, Other: 1 } } },
+  { analysis_summary: null },
+];
+
+describe('listExportableParams', () => {
+  const params = listExportableParams(dailyTemplate, statuses);
+  it('starts with the two fixed session metrics', () => {
+    expect(params.slice(0, 2)).toEqual([
+      expect.objectContaining({ id: '__total__', label: 'Total attempts', group: 'metrics', kind: 'total' }),
+      expect.objectContaining({ id: '__success_rate__', label: 'Success rate', group: 'metrics', kind: 'success_rate' }),
+    ]);
+  });
+  it('adds one metrics entry per dynamic count category, sorted', () => {
+    const cats = params.filter((p) => p.kind === 'category').map((p) => p.label);
+    expect(cats).toEqual(['Failure', 'Other', 'Success']);
+  });
+  it('includes every template field (incl. inactive) in the daily group', () => {
+    const daily = params.filter((p) => p.group === 'daily');
+    expect(daily).toEqual([
+      expect.objectContaining({ label: 'Vitals', kind: 'builtin', statusKey: 'vitals' }),
+      expect.objectContaining({ label: 'Weight (g)', kind: 'custom', fieldId: 'c-weight' }),
+    ]);
+  });
+  it('gives every param a unique id', () => {
+    const ids = params.map((p) => p.id);
+    expect(new Set(ids).size).toBe(ids.length);
+  });
+  it('tolerates empty/missing inputs', () => {
+    expect(listExportableParams(undefined, undefined).length).toBe(2); // just the two fixed metrics
+  });
+});
+
+import { toCSV, csvFilename } from '../src/lib/dataExport';
+
+describe('toCSV', () => {
+  it('emits context line, blank line, header, data (no group)', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Total attempts' },
+      groupAxis: null,
+      columns: [{ id: 'a1', label: 'Alpha', group: null }, { id: 'a2', label: 'Beta', group: null }],
+      rows: [{ member: { label: '2026-07-01' }, values: [5, ''] }, { member: { label: '2026-07-02' }, values: ['', 9] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,Total attempts\n\nDate,Alpha,Beta\n2026-07-01,5,\n2026-07-02,,9',
+    );
+  });
+
+  it('adds a Group header row when subjects are columns', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Total attempts' },
+      groupAxis: 'col',
+      columns: [{ id: 'a1', label: 'Alpha', group: 'Control' }, { id: 'a2', label: 'Beta', group: 'Drug' }],
+      rows: [{ member: { label: '2026-07-01' }, values: [5, 9] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,Total attempts\n\nGroup,Control,Drug\nDate,Alpha,Beta\n2026-07-01,5,9',
+    );
+  });
+
+  it('adds a leading Group column when subjects are rows', () => {
+    const matrix = {
+      corner: 'Subject',
+      context: { label: 'Date', value: '2026-07-01' },
+      groupAxis: 'row',
+      columns: [{ id: 'p1', label: 'Total attempts', group: 'metrics' }],
+      rows: [
+        { member: { label: 'Alpha', group: 'Control' }, values: [5] },
+        { member: { label: 'Beta', group: 'Drug' }, values: [9] },
+      ],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Date,2026-07-01\n\nGroup,Subject,Total attempts\nControl,Alpha,5\nDrug,Beta,9',
+    );
+  });
+
+  it('escapes commas, quotes, and newlines per RFC 4180', () => {
+    const matrix = {
+      corner: 'Date',
+      context: { label: 'Parameter', value: 'Note, field' },
+      groupAxis: null,
+      columns: [{ id: 'a1', label: 'he said "hi"', group: null }],
+      rows: [{ member: { label: '2026-07-01' }, values: ['line1\nline2'] }],
+    };
+    expect(toCSV(matrix)).toBe(
+      'Parameter,"Note, field"\n\nDate,"he said ""hi"""\n2026-07-01,"line1\nline2"',
+    );
+  });
+});
+
+describe('csvFilename', () => {
+  it('slugifies the experiment title and parameter label', () => {
+    expect(csvFilename('My Study #1', 'Success rate')).toBe('My-Study-1-Success-rate.csv');
+  });
+  it('falls back to "export" when both slugs are empty', () => {
+    expect(csvFilename('', '')).toBe('export.csv');
+  });
+});
+
+import { subjectGroupValue } from '../src/lib/dataExport';
+
+describe('subjectGroupValue', () => {
+  const animal = { animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { sex: 'M', cohort: '' } };
+  it('returns null when no group field', () => {
+    expect(subjectGroupValue(animal, '__none__')).toBeNull();
+    expect(subjectGroupValue(animal, '')).toBeNull();
+  });
+  it('resolves name / id / subject_info fields', () => {
+    expect(subjectGroupValue(animal, '__name__')).toBe('Alpha');
+    expect(subjectGroupValue(animal, '__id__')).toBe('R-001');
+    expect(subjectGroupValue(animal, 'sex')).toBe('M');
+  });
+  it('renders missing or empty values as an em dash', () => {
+    expect(subjectGroupValue(animal, 'cohort')).toBe('—');
+    expect(subjectGroupValue({}, 'sex')).toBe('—');
+  });
+});
+
+import { listSubjectMembers } from '../src/lib/dataExport';
+
+describe('listSubjectMembers', () => {
+  const animals = [
+    { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+    { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+    { id: 'a3', animal_name: 'Gamma', animal_id_string: 'R-003', subject_info: { grp: 'Control' } },
+  ];
+  it('orders by name and carries group=null when no group field', () => {
+    const m = listSubjectMembers(animals, '__none__');
+    expect(m.map((s) => s.label)).toEqual(['Alpha', 'Beta', 'Gamma']);
+    expect(m.every((s) => s.group === null)).toBe(true);
+    expect(m[0]).toMatchObject({ id: 'a1', animalId: 'a1' });
+  });
+  it('clusters by group value then name when grouping is on', () => {
+    const m = listSubjectMembers(animals, 'grp');
+    expect(m.map((s) => [s.group, s.label])).toEqual([
+      ['Control', 'Alpha'], ['Control', 'Gamma'], ['Drug', 'Beta'],
+    ]);
+  });
+  it('disambiguates duplicate names with the id string', () => {
+    const dup = [
+      { id: 'a1', animal_name: 'Rat', animal_id_string: 'R-001' },
+      { id: 'a2', animal_name: 'Rat', animal_id_string: 'R-002' },
+    ];
+    expect(listSubjectMembers(dup, '__none__').map((s) => s.label)).toEqual(['Rat (R-001)', 'Rat (R-002)']);
+  });
+});
+
+import { numericFieldVal, listSampleMembers, buildSampleIndex } from '../src/lib/dataExport';
+
+const sDaily = [{ fieldId: 'c-w', key: 'w', label: 'Weight', builtin: false, active: true }];
+const sStatuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', custom_fields: { 'c-w': '250' } },
+  { animal_id: 'a1', date: '2026-07-03T00:00:00Z', custom_fields: { 'c-w': '260' } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', custom_fields: { 'c-w': '250' } },
+];
+
+describe('numericFieldVal', () => {
+  it('reads builtin via key and custom via fieldId, parsed to number', () => {
+    expect(numericFieldVal({ weight: '250' }, { builtin: true, key: 'weight' })).toBe(250);
+    expect(numericFieldVal({ custom_fields: { 'c-w': '12.5' } }, { builtin: false, fieldId: 'c-w' })).toBe(12.5);
+  });
+  it('returns null for non-numeric, missing, or no field', () => {
+    expect(numericFieldVal({ custom_fields: { 'c-w': 'abc' } }, { builtin: false, fieldId: 'c-w' })).toBeNull();
+    expect(numericFieldVal({}, { builtin: true, key: 'weight' })).toBeNull();
+    expect(numericFieldVal({ weight: 1 }, null)).toBeNull();
+  });
+});
+
+describe('listSampleMembers', () => {
+  it('date: distinct dates sorted', () => {
+    expect(listSampleMembers(sStatuses, '__date__', sDaily).map((m) => m.sampleValue)).toEqual(['2026-07-01', '2026-07-03']);
+  });
+  it('# days reach: 1..max records per subject', () => {
+    expect(listSampleMembers(sStatuses, '__days__', sDaily).map((m) => m.sampleValue)).toEqual([1, 2]);
+  });
+  it('daily field: distinct numeric values sorted ascending', () => {
+    expect(listSampleMembers(sStatuses, 'c-w', sDaily).map((m) => m.sampleValue)).toEqual([250, 260]);
+  });
+});
+
+describe('buildSampleIndex', () => {
+  it('date coord maps animalId -> dateKey -> status', () => {
+    const idx = buildSampleIndex(sStatuses, '__date__', sDaily);
+    expect(idx.get('a1').get('2026-07-03').date).toContain('2026-07-03');
+  });
+  it('# days reach assigns per-subject ordinals in date order', () => {
+    const idx = buildSampleIndex(sStatuses, '__days__', sDaily);
+    expect(idx.get('a1').get(1).date).toContain('2026-07-01');
+    expect(idx.get('a1').get(2).date).toContain('2026-07-03');
+    expect(idx.get('a2').get(1).date).toContain('2026-07-01');
+    expect(idx.get('a2').has(2)).toBe(false);
+  });
+  it('daily field maps numeric value to first status by date', () => {
+    const idx = buildSampleIndex(sStatuses, 'c-w', sDaily);
+    expect(idx.get('a1').get(250).date).toContain('2026-07-01');
+    expect(idx.get('a1').get(260).date).toContain('2026-07-03');
+  });
+  it('# days reach counts per-status, not per-distinct-date (same-day statuses get separate ordinals)', () => {
+    const sameDay = [
+      { animal_id: 'z1', date: '2026-07-01T08:00:00Z', analysis_summary: { total: 1 } },
+      { animal_id: 'z1', date: '2026-07-01T20:00:00Z', analysis_summary: { total: 2 } },
+    ];
+    const idx = buildSampleIndex(sameDay, '__days__', []);
+    expect(idx.get('z1').has(1)).toBe(true);
+    expect(idx.get('z1').has(2)).toBe(true);
+    expect(idx.get('z1').has(3)).toBe(false);
+  });
+});
+
+import { buildSubjectSeriesMatrix } from '../src/lib/dataExport';
+
+const ssAnimals = [
+  { id: 'a1', animal_name: 'Alpha', animal_id_string: 'R-001', subject_info: { grp: 'Control' } },
+  { id: 'a2', animal_name: 'Beta', animal_id_string: 'R-002', subject_info: { grp: 'Drug' } },
+];
+const ssStatuses = [
+  { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5 } },
+  { animal_id: 'a1', date: '2026-07-02T00:00:00Z', analysis_summary: { total: 7 } },
+  { animal_id: 'a2', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 9 } },
+];
+const totalParam = { id: '__total__', label: 'Total attempts', kind: 'total', group: 'metrics' };
+
+describe('buildSubjectSeriesMatrix', () => {
+  it('date X: subjects as columns, date rows, blank where missing, context names the metric', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: '__none__' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.corner).toBe('Date');
+    expect(m.context).toEqual({ label: 'Data', value: 'Total attempts' });
+    expect(m.groupAxis).toBeNull();
+    expect(m.columns.map((c) => c.label)).toEqual(['Alpha', 'Beta']);
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01', '2026-07-02']);
+    expect(m.rows[0].values).toEqual([5, 9]);
+    expect(m.rows[1].values).toEqual([7, '']);
+  });
+  it('# days reach X: rows align each subject by day ordinal', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__days__', dataParam: totalParam, groupField: '__none__' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.corner).toBe('# Days Reach (ordinal)');
+    expect(m.rows.map((r) => r.member.label)).toEqual(['1', '2']);
+    expect(m.rows[0].values).toEqual([5, 9]);
+    expect(m.rows[1].values).toEqual([7, '']);
+  });
+  it('grouping sets groupAxis col and clusters subjects', () => {
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: 'grp' },
+      { statuses: ssStatuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.groupAxis).toBe('col');
+    expect(m.columns.map((c) => [c.group, c.label])).toEqual([['Control', 'Alpha'], ['Drug', 'Beta']]);
+  });
+  it('drops entirely-blank rows', () => {
+    const statuses = [
+      { animal_id: 'a1', date: '2026-07-01T00:00:00Z', analysis_summary: { total: 5 } },
+      { animal_id: 'a1', date: '2026-07-05T00:00:00Z', analysis_summary: null },
+    ];
+    const m = buildSubjectSeriesMatrix(
+      { xField: '__date__', dataParam: totalParam, groupField: '__none__' },
+      { statuses, animals: ssAnimals, dailyTemplate: [] },
+    );
+    expect(m.rows.map((r) => r.member.label)).toEqual(['2026-07-01']);
+  });
+});

frontend/tests/setup.js

@@ -0,0 +1,13 @@
+import '@testing-library/jest-dom';
+
+// Suppress noisy act() warnings from async state updates in useEffect hooks.
+// All assertions still run — this only silences the console.error spam that
+// causes OOM crashes when running the full suite.
+const originalError = console.error;
+beforeAll(() => {
+  console.error = (...args) => {
+    if (typeof args[0] === 'string' && args[0].includes('not wrapped in act')) return;
+    originalError(...args);
+  };
+});
+afterAll(() => { console.error = originalError; });