feat(template): stable fieldId per field — custom_fields keyed by UUID, not label slug

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"],
+    "testMatch": [
-    "setupFilesAfterFramework": [],
+      "**/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/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 {
@@ -11,6 +12,7 @@ model Experiment {
   id         String   @id @default(uuid())
   title      String
   created_at DateTime @default(now())
+  template   Json     @default("[]")
   animals    Animal[]
 
   @@map("experiments")
@@ -35,6 +37,7 @@ model DailyStatus {
   vitals                 String?
   treatment              String?
   notes                  String?
+  custom_fields          Json?
   animal                 Animal   @relation(fields: [animal_id], references: [id], onDelete: Cascade)
 
   @@map("daily_statuses")

backend/src/app.js

@@ -0,0 +1,60 @@
+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 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() });
+});
+
+// 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((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');
-
+    // Note: migrations are run by docker-entrypoint.sh before this process starts
-    // Run migrations on startup in production
-    if (process.env.NODE_ENV === 'production') {
-      const { execSync } = require('child_process');
-      execSync('npx prisma migrate deploy', { stdio: 'inherit' });
-    }
-
     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/defaultTemplate.js

@@ -0,0 +1,29 @@
+/**
+ * The default daily-record template applied to every new experiment.
+ *
+ * Builtin fields have FIXED fieldIds so they are stable across all experiments
+ * and can never be confused with user-created fields, even if a user creates a
+ * custom field with the same label.
+ *
+ * `fieldId`     — stable UUID used as the storage key; never changes even if
+ *                 the field is renamed, reordered, or temporarily removed
+ * `key`         — human-readable slug (display only, not used for storage)
+ * `builtin`     — true: value stored in the dedicated column of daily_statuses
+ *                 false: value stored in daily_statuses.custom_fields[fieldId]
+ * `active`      — false: field is hidden (data preserved)
+ */
+const DEFAULT_TEMPLATE = [
+  { fieldId: '00000000-0000-0000-0000-000000000001', key: 'experiment_description', label: 'Experiment Description', type: 'textarea', builtin: true,  active: true },
+  { fieldId: '00000000-0000-0000-0000-000000000002', key: 'vitals',                 label: 'Vitals',                  type: 'text',     builtin: true,  active: true },
+  { fieldId: '00000000-0000-0000-0000-000000000003', key: 'treatment',              label: 'Treatment',               type: 'text',     builtin: true,  active: true },
+  { fieldId: '00000000-0000-0000-0000-000000000004', key: 'notes',                  label: 'Notes',                   type: 'textarea', builtin: true,  active: true },
+];
+
+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
+      // Shared audit writer — called by both res.json and res.send interceptors
-      const originalJson = res.json.bind(res);
+      async function writeAuditLog() {
-      res.json = async function (data) {
-        // Only log on successful mutations
         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/animals.js

@@ -5,7 +5,7 @@ const auditMiddleware = require('../middleware/auditMiddleware');
 const { validateRequest } = require('../middleware/errorHandler');
 
 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}$/i).withMessage('experiment_id must be a valid UUID'),
   body('animal_id_string').trim().notEmpty().withMessage('animal_id_string is required'),
   body('animal_name').trim().notEmpty().withMessage('animal_name is required'),
 ];
@@ -18,7 +18,7 @@ const animalUpdateValidation = [
 // GET /api/animals?experimentId=<uuid> — list for experiment
 router.get(
   '/',
-  [query('experimentId').optional().isUUID().withMessage('experimentId must be a valid UUID')],
+  [query('experimentId').optional().matches(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i).withMessage('experimentId must be a valid UUID')],
   validateRequest,
   async (req, res, next) => {
     try {

backend/src/routes/auditLogs.js

@@ -7,8 +7,8 @@ const { validateRequest } = require('../middleware/errorHandler');
 router.get(
   '/',
   [
-    query('tableName').optional().isString(),
+    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().isUUID().withMessage('recordId must be a valid UUID'),
+    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

@@ -5,12 +5,13 @@ const auditMiddleware = require('../middleware/auditMiddleware');
 const { validateRequest } = require('../middleware/errorHandler');
 
 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('custom_fields').optional().isObject().withMessage('custom_fields must be an object'),
 ];
 
 const statusUpdateValidation = [
@@ -19,12 +20,13 @@ const statusUpdateValidation = [
   body('vitals').optional().isString(),
   body('treatment').optional().isString(),
   body('notes').optional().isString(),
+  body('custom_fields').optional().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 +37,11 @@ router.get(
         include: { animal: { select: { animal_name: true, animal_id_string: true } } },
       });
       res.json(statuses);
-    } catch (err) {
+    } catch (err) { next(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 +50,13 @@ router.get('/:id', async (req, res, next) => {
     });
     if (!status) return res.status(404).json({ error: 'Daily status not found' });
     res.json(status);
-  } catch (err) {
+  } catch (err) { next(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 +65,17 @@ router.post('/', statusValidation, validateRequest, async (req, res, next) => {
         vitals,
         treatment,
         notes,
+        custom_fields: custom_fields ?? {},
       },
     });
-
     await prisma.auditLog.create({
-      data: {
+      data: { table_name: 'daily_statuses', record_id: status.id, action: 'CREATE', changes: { before: null, after: status } },
-        table_name: 'daily_statuses',
-        record_id: status.id,
-        action: 'CREATE',
-        changes: { before: null, after: status },
-      },
     });
-
     res.status(201).json(status);
-  } catch (err) {
+  } catch (err) { next(err); }
-    next(err);
-  }
 });
 
-// PUT /api/daily-statuses/:id — update
+// PUT /api/daily-statuses/:id
 router.put(
   '/:id',
   auditMiddleware('daily_statuses', prisma.dailyStatus),
@@ -93,26 +83,22 @@ 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 (date !== undefined)                   data.date = new Date(date);
-      if (experiment_description !== undefined) data.experiment_description = experiment_description;
+      if (experiment_description !== undefined)  data.experiment_description = experiment_description;
-      if (vitals !== undefined) data.vitals = vitals;
+      if (vitals !== undefined)                  data.vitals = vitals;
-      if (treatment !== undefined) data.treatment = treatment;
+      if (treatment !== undefined)               data.treatment = treatment;
-      if (notes !== undefined) data.notes = notes;
+      if (notes !== undefined)                   data.notes = notes;
+      if (custom_fields !== undefined)           data.custom_fields = custom_fields;
 
-      const status = await prisma.dailyStatus.update({
+      const status = await prisma.dailyStatus.update({ where: { id: req.params.id }, data });
-        where: { id: req.params.id },
-        data,
-      });
       res.json(status);
-    } catch (err) {
+    } catch (err) { next(err); }
-      next(err);
-    }
   }
 );
 
-// DELETE /api/daily-statuses/:id — delete
+// DELETE /api/daily-statuses/:id
 router.delete(
   '/:id',
   auditMiddleware('daily_statuses', prisma.dailyStatus),
@@ -120,9 +106,7 @@ router.delete(
     try {
       await prisma.dailyStatus.delete({ where: { id: req.params.id } });
       res.status(204).send();
-    } catch (err) {
+    } catch (err) { next(err); }
-      next(err);
-    }
   }
 );
 

backend/src/routes/experiments.js

@@ -3,12 +3,77 @@ const { body } = require('express-validator');
 const prisma = require('../lib/prisma');
 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`;
+  }
+  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()),
+  }));
+}
+
+// ── Experiment CRUD ────────────────────────────────────────────────────────────
+
+// GET /api/experiments
 router.get('/', async (req, res, next) => {
   try {
     const experiments = await prisma.experiment.findMany({
@@ -16,12 +81,10 @@ router.get('/', async (req, res, next) => {
       include: { _count: { select: { animals: true } } },
     });
     res.json(experiments);
-  } catch (err) {
+  } catch (err) { next(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 +92,25 @@ 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) {
+  } catch (err) { next(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: {
+      data: { table_name: 'experiments', record_id: experiment.id, action: 'CREATE', changes: { before: null, after: experiment } },
-        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) {
+  } catch (err) { next(err); }
-    next(err);
-  }
 });
 
-// PUT /api/experiments/:id — update
+// PUT /api/experiments/:id
 router.put(
   '/:id',
   auditMiddleware('experiments', prisma.experiment),
@@ -66,18 +119,14 @@ router.put(
   async (req, res, next) => {
     try {
       const { title } = req.body;
-      const experiment = await prisma.experiment.update({
+      const experiment = await prisma.experiment.update({ where: { id: req.params.id }, data: { title } });
-        where: { id: req.params.id },
+      experiment.template = ensureFieldIds(resolveTemplate(experiment.template));
-        data: { title },
-      });
       res.json(experiment);
-    } catch (err) {
+    } catch (err) { next(err); }
-      next(err);
-    }
   }
 );
 
-// DELETE /api/experiments/:id — delete
+// DELETE /api/experiments/:id
 router.delete(
   '/:id',
   auditMiddleware('experiments', prisma.experiment),
@@ -85,10 +134,51 @@ router.delete(
     try {
       await prisma.experiment.delete({ where: { id: req.params.id } });
       res.status(204).send();
-    } catch (err) {
+    } catch (err) { next(err); }
-      next(err);
-    }
   }
 );
 
+// ── 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); }
+});
+
 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 +1,120 @@
+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' }) })
+    );
+  });
+});

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/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/experiments.test.js

@@ -0,0 +1,138 @@
+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');
+  });
+});

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

@@ -11,8 +11,9 @@ services:
       POSTGRES_DB: ${POSTGRES_DB:-experiments_db}
     volumes:
       - postgres_data:/var/lib/postgresql/data
-    ports:
+    # Port NOT exposed to host — only reachable by backend via internal Docker network
-      - "5432:5432"
+    expose:
+      - "5432"
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U ${POSTGRES_USER:-expuser} -d ${POSTGRES_DB:-experiments_db}"]
       interval: 10s
@@ -32,13 +33,17 @@ services:
       DATABASE_URL: postgresql://${POSTGRES_USER:-expuser}:${POSTGRES_PASSWORD:-exppassword}@postgres:5432/${POSTGRES_DB:-experiments_db}
       NODE_ENV: production
       PORT: 3001
+      CORS_ORIGIN: "http://localhost:52867"
+    # 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"]
+      test: ["CMD-SHELL", "wget -qO- http://127.0.0.1:3001/health || exit 1"]
-      interval: 15s
+      interval: 10s
       timeout: 5s
-      retries: 5
+      retries: 10
+      start_period: 40s
 
   frontend:
     build:

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/index.html

@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Animal Experiments Database</title>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script type="module" src="/src/main.jsx"></script>
+  </body>
+</html>

frontend/package.json

@@ -0,0 +1,49 @@
+{
+  "name": "experiments-frontend",
+  "version": "1.0.0",
+  "private": true,
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview",
+    "test": "jest --runInBand --forceExit",
+    "test:coverage": "jest --runInBand --forceExit --coverage",
+    "test:e2e": "playwright test"
+  },
+  "dependencies": {
+    "axios": "^1.7.2",
+    "date-fns": "^3.6.0",
+    "react": "^18.3.1",
+    "react-dom": "^18.3.1",
+    "react-router-dom": "^6.24.0"
+  },
+  "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": "^14.3.1",
+    "@testing-library/user-event": "^14.5.2",
+    "@vitejs/plugin-react": "^4.2.1",
+    "autoprefixer": "^10.4.19",
+    "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"
+  },
+  "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/postcss.config.js

@@ -0,0 +1,6 @@
+module.exports = {
+  plugins: {
+    tailwindcss: {},
+    autoprefixer: {},
+  },
+};

frontend/src/App.jsx

@@ -0,0 +1,50 @@
+import React from 'react';
+import { Routes, Route, Link, useLocation } from 'react-router-dom';
+import Dashboard from './pages/Dashboard';
+import ExperimentDetail from './pages/ExperimentDetail';
+import AnimalDetail from './pages/AnimalDetail';
+
+function Navbar() {
+  return (
+    <header className="bg-white border-b border-gray-200 sticky top-0 z-40">
+      <div className="max-w-5xl mx-auto px-4 h-14 flex items-center justify-between">
+        <Link to="/" className="flex items-center gap-2 font-bold text-gray-900 hover:text-blue-700 transition-colors">
+          <svg className="w-6 h-6 text-blue-600" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2}
+              d="M19.428 15.428a2 2 0 00-1.022-.547l-2.387-.477a6 6 0 00-3.86.517l-.318.158a6 6 0 01-3.86.517L6.05 15.21a2 2 0 00-1.806.547M8 4h8l-1 1v5.172a2 2 0 00.586 1.414l5 5c1.26 1.26.367 3.414-1.415 3.414H4.828c-1.782 0-2.674-2.154-1.414-3.414l5-5A2 2 0 009 10.172V5L8 4z" />
+          </svg>
+          Animal Experiments DB
+        </Link>
+        <nav className="text-sm text-gray-500">
+          <Link to="/" className="hover:text-blue-600 transition-colors">Dashboard</Link>
+        </nav>
+      </div>
+    </header>
+  );
+}
+
+function NotFound() {
+  return (
+    <div className="max-w-5xl mx-auto px-4 py-20 text-center">
+      <h1 className="text-4xl font-bold text-gray-300 mb-4">404</h1>
+      <p className="text-gray-500 mb-6">Page not found.</p>
+      <Link to="/" className="text-blue-600 hover:underline">← Return to Dashboard</Link>
+    </div>
+  );
+}
+
+export default function App() {
+  return (
+    <div className="min-h-screen bg-gray-50">
+      <Navbar />
+      <main>
+        <Routes>
+          <Route path="/" element={<Dashboard />} />
+          <Route path="/experiments/:id" element={<ExperimentDetail />} />
+          <Route path="/animals/:id" element={<AnimalDetail />} />
+          <Route path="*" element={<NotFound />} />
+        </Routes>
+      </main>
+    </div>
+  );
+}

frontend/src/api/client.js

@@ -0,0 +1,59 @@
+import axios from 'axios';
+
+const api = axios.create({
+  baseURL: '/api',
+  headers: { 'Content-Type': 'application/json' },
+  timeout: 10000,
+});
+
+// Response interceptor — normalize errors
+api.interceptors.response.use(
+  (res) => res,
+  (err) => {
+    const message =
+      err.response?.data?.error ||
+      err.response?.data?.message ||
+      err.message ||
+      'An unexpected error occurred';
+    const details = err.response?.data?.details || null;
+    return Promise.reject({ message, details, status: err.response?.status });
+  }
+);
+
+export default api;
+
+// ── Experiments ────────────────────────────────────────────────────────────────
+export const experimentsApi = {
+  list: () => api.get('/experiments').then((r) => r.data),
+  get: (id) => api.get(`/experiments/${id}`).then((r) => r.data),
+  create: (data) => api.post('/experiments', data).then((r) => r.data),
+  update: (id, data) => api.put(`/experiments/${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/${id}/template`, template).then((r) => r.data),
+};
+
+// ── Animals ───────────────────────────────────────────────────────────────────
+export const animalsApi = {
+  list: (experimentId) =>
+    api.get('/animals', { params: { experimentId } }).then((r) => r.data),
+  get: (id) => api.get(`/animals/${id}`).then((r) => r.data),
+  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}`),
+};
+
+// ── Daily Statuses ─────────────────────────────────────────────────────────────
+export const dailyStatusesApi = {
+  list: (animalId) =>
+    api.get('/daily-statuses', { params: { animalId } }).then((r) => r.data),
+  get: (id) => api.get(`/daily-statuses/${id}`).then((r) => r.data),
+  create: (data) => api.post('/daily-statuses', data).then((r) => r.data),
+  update: (id, data) => api.put(`/daily-statuses/${id}`, data).then((r) => r.data),
+  delete: (id) => api.delete(`/daily-statuses/${id}`),
+};
+
+// ── Audit Logs ────────────────────────────────────────────────────────────────
+export const auditLogsApi = {
+  list: (params) => api.get('/audit-logs', { params }).then((r) => r.data),
+};

frontend/src/components/AnimalForm.jsx

@@ -0,0 +1,96 @@
+import React, { useState, useEffect } from 'react';
+import Button from './ui/Button';
+import FormField, { Input } from './ui/FormField';
+import Alert from './ui/Alert';
+import { animalsApi } from '../api/client';
+
+export default function AnimalForm({ existing, experimentId, onSuccess, onCancel }) {
+  const [fields, setFields] = useState({
+    animal_id_string: existing?.animal_id_string ?? '',
+    animal_name: existing?.animal_name ?? '',
+  });
+  const [errors, setErrors] = useState({});
+  const [apiError, setApiError] = useState(null);
+  const [loading, setLoading] = useState(false);
+
+  useEffect(() => {
+    setFields({
+      animal_id_string: existing?.animal_id_string ?? '',
+      animal_name: existing?.animal_name ?? '',
+    });
+    setErrors({});
+    setApiError(null);
+  }, [existing]);
+
+  const set = (k) => (e) => setFields((f) => ({ ...f, [k]: e.target.value }));
+
+  function validate() {
+    const e = {};
+    if (!fields.animal_id_string.trim()) e.animal_id_string = 'Animal ID is required';
+    if (!fields.animal_name.trim()) e.animal_name = 'Animal name is required';
+    setErrors(e);
+    return Object.keys(e).length === 0;
+  }
+
+  async function handleSubmit(e) {
+    e.preventDefault();
+    if (!validate()) return;
+    setLoading(true);
+    setApiError(null);
+    try {
+      const payload = {
+        animal_id_string: fields.animal_id_string.trim(),
+        animal_name: fields.animal_name.trim(),
+      };
+      const result = existing
+        ? await animalsApi.update(existing.id, payload)
+        : await animalsApi.create({ ...payload, experiment_id: experimentId });
+      onSuccess(result);
+    } catch (err) {
+      setApiError(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  return (
+    <form onSubmit={handleSubmit} noValidate className="space-y-4">
+      {apiError && (
+        <Alert
+          type="error"
+          message={apiError.message}
+          details={apiError.details}
+          onDismiss={() => setApiError(null)}
+        />
+      )}
+      <FormField label="Animal ID" name="animal_id_string" error={errors.animal_id_string} required>
+        <Input
+          name="animal_id_string"
+          value={fields.animal_id_string}
+          onChange={set('animal_id_string')}
+          placeholder="e.g. M-001"
+          required
+          disabled={loading}
+        />
+      </FormField>
+      <FormField label="Animal Name" name="animal_name" error={errors.animal_name} required>
+        <Input
+          name="animal_name"
+          value={fields.animal_name}
+          onChange={set('animal_name')}
+          placeholder="e.g. Whiskers"
+          required
+          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' : 'Add Animal'}
+        </Button>
+      </div>
+    </form>
+  );
+}

frontend/src/components/AuditLogSection.jsx

@@ -0,0 +1,113 @@
+import React, { useEffect, useState } from 'react';
+import { auditLogsApi } from '../api/client';
+import { format } from 'date-fns';
+
+function DiffView({ changes }) {
+  const { before, after } = changes || {};
+  if (!before && after) {
+    return <span className="text-green-700 text-xs">Created: {JSON.stringify(after, null, 2)}</span>;
+  }
+  if (before && !after) {
+    return <span className="text-red-700 text-xs">Deleted record</span>;
+  }
+  if (before && after) {
+    const keys = Object.keys({ ...before, ...after }).filter(
+      (k) => JSON.stringify(before[k]) !== JSON.stringify(after[k])
+    );
+    if (keys.length === 0) return <span className="text-gray-400 text-xs">No field changes detected</span>;
+    return (
+      <dl className="text-xs space-y-1">
+        {keys.map((k) => (
+          <div key={k} className="grid grid-cols-3 gap-2">
+            <dt className="font-medium text-gray-600">{k}</dt>
+            <dd className="text-red-600 line-through col-span-1 truncate">{String(before[k] ?? '')}</dd>
+            <dd className="text-green-700 col-span-1 truncate">{String(after[k] ?? '')}</dd>
+          </div>
+        ))}
+      </dl>
+    );
+  }
+  return null;
+}
+
+const ACTION_BADGE = {
+  CREATE: 'bg-green-100 text-green-800',
+  UPDATE: 'bg-yellow-100 text-yellow-800',
+  DELETE: 'bg-red-100 text-red-800',
+};
+
+export default function AuditLogSection({ tableName, recordId }) {
+  const [logs, setLogs] = useState([]);
+  const [total, setTotal] = useState(0);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [expanded, setExpanded] = useState(null);
+
+  useEffect(() => {
+    setLoading(true);
+    auditLogsApi
+      .list({ tableName, recordId, limit: 50 })
+      .then(({ logs, total }) => {
+        setLogs(logs);
+        setTotal(total);
+      })
+      .catch((e) => setError(e.message))
+      .finally(() => setLoading(false));
+  }, [tableName, recordId]);
+
+  return (
+    <section aria-label="Modification History" className="mt-8">
+      <h3 className="text-base font-semibold text-gray-800 mb-3 flex items-center gap-2">
+        <svg className="w-4 h-4 text-gray-500" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2}
+            d="M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z" />
+        </svg>
+        Modification History
+        {total > 0 && (
+          <span className="text-xs font-normal text-gray-500">({total} entries)</span>
+        )}
+      </h3>
+
+      {loading && <p className="text-sm text-gray-500">Loading history…</p>}
+      {error && <p className="text-sm text-red-600">{error}</p>}
+      {!loading && !error && logs.length === 0 && (
+        <p className="text-sm text-gray-400 italic">No modification history yet.</p>
+      )}
+
+      {logs.length > 0 && (
+        <div className="border border-gray-200 rounded-lg overflow-hidden divide-y divide-gray-100">
+          {logs.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"
+                onClick={() => setExpanded(expanded === log.id ? null : log.id)}
+                aria-expanded={expanded === log.id}
+              >
+                <span className={`shrink-0 px-2 py-0.5 rounded text-xs font-semibold ${ACTION_BADGE[log.action] || 'bg-gray-100 text-gray-700'}`}>
+                  {log.action}
+                </span>
+                <span className="text-xs text-gray-500 shrink-0">
+                  {format(new Date(log.timestamp), 'yyyy-MM-dd HH:mm:ss')}
+                </span>
+                <span className="text-xs text-gray-400 truncate flex-1">
+                  {log.table_name} / {log.record_id}
+                </span>
+                <svg
+                  className={`w-4 h-4 text-gray-400 shrink-0 transition-transform ${expanded === log.id ? 'rotate-180' : ''}`}
+                  fill="none" viewBox="0 0 24 24" stroke="currentColor"
+                >
+                  <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
+                </svg>
+              </button>
+              {expanded === log.id && (
+                <div className="px-4 pb-3 bg-gray-50 border-t border-gray-100">
+                  <DiffView changes={log.changes} />
+                </div>
+              )}
+            </div>
+          ))}
+        </div>
+      )}
+    </section>
+  );
+}

frontend/src/components/DailyStatusForm.jsx

@@ -0,0 +1,139 @@
+import React, { useState, useEffect } from 'react';
+import { format } from 'date-fns';
+import Button from './ui/Button';
+import FormField, { Input, Textarea } from './ui/FormField';
+import Alert from './ui/Alert';
+import { dailyStatusesApi } from '../api/client';
+
+const BUILTIN_KEYS = new Set(['experiment_description', 'vitals', 'treatment', 'notes']);
+
+/** 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, template = [], onSuccess, onCancel }) {
+  const today = format(new Date(), 'yyyy-MM-dd');
+
+  // Active fields from template (date is always first and handled separately)
+  const activeFields = template.filter((f) => f.active);
+
+  function buildInitialValues() {
+    const vals = { date: existing ? format(new Date(existing.date), 'yyyy-MM-dd') : 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);
+
+  useEffect(() => {
+    setValues(buildInitialValues());
+    setErrors({});
+    setApiError(null);
+  }, [existing, template]);
+
+  const set = (key) => (e) => setValues((v) => ({ ...v, [key]: e.target.value }));
+
+  function validate() {
+    const e = {};
+    if (!values.date) {
+      e.date = 'Date is required';
+    } 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 handleSubmit(e) {
+    e.preventDefault();
+    if (!validate()) return;
+    setLoading(true);
+    setApiError(null);
+    try {
+      // Separate builtin values from custom_fields
+      const builtin = {};
+      const custom = {};
+      for (const f of activeFields) {
+        const val = values[f.key] || null;
+        if (f.builtin) {
+          builtin[f.key] = val;
+        } else {
+          // Always key by fieldId so renaming or recreating a field never
+          // collides with or orphans data from a different field.
+          custom[f.fieldId] = val;
+        }
+      }
+
+      // Preserve custom_fields for fields not in the current active template
+      // (e.g. a field was hidden after this record was created).
+      const existingCustom = existing?.custom_fields ?? {};
+      const mergedCustom = { ...existingCustom, ...custom };
+
+      const payload = { date: values.date, ...builtin, custom_fields: mergedCustom };
+
+      const result = existing
+        ? await dailyStatusesApi.update(existing.id, payload)
+        : await dailyStatusesApi.create({ ...payload, animal_id: animalId });
+
+      onSuccess(result);
+    } catch (err) {
+      setApiError(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  return (
+    <form onSubmit={handleSubmit} noValidate className="space-y-4">
+      {apiError && (
+        <Alert type="error" message={apiError.message} details={apiError.details} onDismiss={() => setApiError(null)} />
+      )}
+
+      {/* Date — always present */}
+      <FormField label="Date" name="date" error={errors.date} required>
+        <Input type="date" name="date" value={values.date} onChange={set('date')} required disabled={loading} />
+      </FormField>
+
+      {/* Dynamic fields from template */}
+      {activeFields.map((field) => (
+        <FormField key={field.key} label={field.label} name={field.key}>
+          {field.type === 'textarea' ? (
+            <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}
+            />
+          )}
+        </FormField>
+      ))}
+
+      {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 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>
+    </form>
+  );
+}

frontend/src/components/ExperimentForm.jsx

@@ -0,0 +1,74 @@
+import React, { useState, useEffect } from 'react';
+import Button from './ui/Button';
+import FormField, { Input } from './ui/FormField';
+import Alert from './ui/Alert';
+import { experimentsApi } from '../api/client';
+
+export default function ExperimentForm({ existing, onSuccess, onCancel }) {
+  const [title, setTitle] = useState(existing?.title ?? '');
+  const [errors, setErrors] = useState({});
+  const [apiError, setApiError] = useState(null);
+  const [loading, setLoading] = useState(false);
+
+  useEffect(() => {
+    setTitle(existing?.title ?? '');
+    setErrors({});
+    setApiError(null);
+  }, [existing]);
+
+  function validate() {
+    const e = {};
+    if (!title.trim()) e.title = 'Title is required';
+    else if (title.trim().length > 255) e.title = 'Title must be 255 characters or fewer';
+    setErrors(e);
+    return Object.keys(e).length === 0;
+  }
+
+  async function handleSubmit(e) {
+    e.preventDefault();
+    if (!validate()) return;
+    setLoading(true);
+    setApiError(null);
+    try {
+      const result = existing
+        ? await experimentsApi.update(existing.id, { title: title.trim() })
+        : await experimentsApi.create({ title: title.trim() });
+      onSuccess(result);
+    } catch (err) {
+      setApiError(err);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  return (
+    <form onSubmit={handleSubmit} noValidate className="space-y-4">
+      {apiError && (
+        <Alert
+          type="error"
+          message={apiError.message}
+          details={apiError.details}
+          onDismiss={() => setApiError(null)}
+        />
+      )}
+      <FormField label="Experiment Title" name="title" error={errors.title} required>
+        <Input
+          name="title"
+          value={title}
+          onChange={(e) => setTitle(e.target.value)}
+          placeholder="e.g. Drug Efficacy Study – Q3"
+          required
+          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' : 'Create Experiment'}
+        </Button>
+      </div>
+    </form>
+  );
+}

frontend/src/components/TemplateEditor.jsx

@@ -0,0 +1,233 @@
+import React, { useState, useEffect } from 'react';
+import { experimentsApi } from '../api/client';
+import Button from './ui/Button';
+import Alert from './ui/Alert';
+
+// Slugify a label into a valid field key
+function toKey(label) {
+  return label
+    .toLowerCase()
+    .trim()
+    .replace(/[^a-z0-9]+/g, '_')
+    .replace(/^_+|_+$/g, '')
+    .slice(0, 64);
+}
+
+function FieldRow({ field, onChange, onToggle, onRemove, allKeys }) {
+  const [labelDraft, setLabelDraft] = useState(field.label);
+  const [labelError, setLabelError] = useState('');
+
+  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; }
+
+    // For custom fields, also ensure the derived key is unique
+    if (!field.builtin) {
+      const newKey = toKey(trimmed);
+      if (!newKey) { setLabelError('Label must contain at least one alphanumeric character'); return; }
+      const duplicate = allKeys.find((k) => k !== field.key && k === newKey);
+      if (duplicate) { setLabelError('A field with this name already exists'); return; }
+    }
+
+    setLabelError('');
+    onChange({ ...field, label: trimmed, key: field.builtin ? field.key : toKey(trimmed) });
+  }
+
+  return (
+    <div className={`flex items-center gap-3 px-4 py-3 rounded-lg border transition-colors ${field.active ? 'bg-white border-gray-200' : 'bg-gray-50 border-gray-100 opacity-60'}`}>
+      {/* Drag handle placeholder (visual only) */}
+      <span className="text-gray-300 cursor-default select-none text-lg leading-none">⠿</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 badge */}
+      <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>
+
+      {/* Toggle active */}
+      <button
+        title={field.active ? 'Hide field' : 'Show field'}
+        aria-label={field.active ? `Hide field ${field.label}` : `Show field ${field.label}`}
+        onClick={() => onToggle(field.key)}
+        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 — only for custom fields */}
+      {!field.builtin && (
+        <button
+          title="Remove field permanently"
+          aria-label={`Remove field ${field.label}`}
+          onClick={() => onRemove(field.key)}
+          className="text-sm px-2 py-1 rounded border border-red-200 text-red-500 hover:bg-red-50 transition-colors"
+        >
+          ✕
+        </button>
+      )}
+    </div>
+  );
+}
+
+export default function TemplateEditor({ experimentId, onClose }) {
+  const [fields, setFields] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [saving, setSaving] = useState(false);
+  const [error, setError] = useState(null);
+  const [success, setSuccess] = useState(false);
+  const [newLabel, setNewLabel] = useState('');
+  const [newType, setNewType] = useState('text');
+  const [addError, setAddError] = useState('');
+
+  useEffect(() => {
+    experimentsApi.getTemplate(experimentId)
+      .then(setFields)
+      .catch((e) => setError(e.message))
+      .finally(() => setLoading(false));
+  }, [experimentId]);
+
+  function updateField(updated) {
+    setFields((prev) => prev.map((f) => f.key === updated.key ? updated : f));
+  }
+
+  function toggleField(key) {
+    setFields((prev) => prev.map((f) => f.key === key ? { ...f, active: !f.active } : f));
+  }
+
+  function removeField(key) {
+    setFields((prev) => prev.filter((f) => f.key !== key));
+  }
+
+  function addField() {
+    const trimmed = newLabel.trim();
+    if (!trimmed) { setAddError('Field name is required'); return; }
+    const key = toKey(trimmed);
+    if (!key) { setAddError('Name must contain at least one alphanumeric character'); return; }
+    if (fields.some((f) => f.key === key)) { setAddError(`A field with key "${key}" already exists`); return; }
+    setAddError('');
+    const fieldId = crypto.randomUUID();
+    setFields((prev) => [...prev, { fieldId, key, label: trimmed, type: newType, builtin: false, active: true }]);
+    setNewLabel('');
+    setNewType('text');
+  }
+
+  async function save() {
+    setSaving(true);
+    setError(null);
+    try {
+      await experimentsApi.updateTemplate(experimentId, fields);
+      setSuccess(true);
+      setTimeout(() => { setSuccess(false); onClose(fields); }, 800);
+    } 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) => (
+              <FieldRow
+                key={field.key}
+                field={field}
+                onChange={updateField}
+                onToggle={toggleField}
+                onRemove={removeField}
+                allKeys={allKeys}
+              />
+            ))}
+          </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" onClick={addField} type="button">+ Add</Button>
+            </div>
+          </div>
+
+          {/* Info note */}
+          <p className="text-xs text-gray-400">
+            <strong>Hide</strong> removes a builtin field from forms while preserving its data.
+            <strong className="ml-1">✕</strong> permanently removes a custom field (data in existing records is not deleted).
+          </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/Alert.jsx

@@ -0,0 +1,33 @@
+import React from 'react';
+
+const styles = {
+  error: 'bg-red-50 border-red-200 text-red-800',
+  success: 'bg-green-50 border-green-200 text-green-800',
+  warning: 'bg-yellow-50 border-yellow-200 text-yellow-800',
+  info: 'bg-blue-50 border-blue-200 text-blue-800',
+};
+
+export default function Alert({ type = 'error', message, details, onDismiss }) {
+  if (!message) return null;
+  return (
+    <div role="alert" className={`rounded-md border px-4 py-3 text-sm ${styles[type]}`}>
+      <div className="flex items-start justify-between gap-2">
+        <div className="flex-1">
+          <p className="font-medium">{message}</p>
+          {details && (
+            <ul className="mt-1 list-disc list-inside space-y-0.5 text-xs opacity-80">
+              {details.map((d, i) => (
+                <li key={i}>{d.field ? `${d.field}: ${d.message}` : d.message}</li>
+              ))}
+            </ul>
+          )}
+        </div>
+        {onDismiss && (
+          <button onClick={onDismiss} className="shrink-0 opacity-60 hover:opacity-100" aria-label="Dismiss">
+            ✕
+          </button>
+        )}
+      </div>
+    </div>
+  );
+}

frontend/src/components/ui/Button.jsx

@@ -0,0 +1,49 @@
+import React from 'react';
+
+const variants = {
+  primary: 'bg-blue-600 hover:bg-blue-700 text-white border-transparent',
+  secondary: 'bg-white hover:bg-gray-50 text-gray-700 border-gray-300',
+  danger: 'bg-red-600 hover:bg-red-700 text-white border-transparent',
+  ghost: 'bg-transparent hover:bg-gray-100 text-gray-600 border-transparent',
+};
+
+const sizes = {
+  sm: 'px-3 py-1.5 text-sm',
+  md: 'px-4 py-2 text-sm',
+  lg: 'px-6 py-3 text-base',
+};
+
+export default function Button({
+  children,
+  variant = 'primary',
+  size = 'md',
+  disabled = false,
+  loading = false,
+  onClick,
+  type = 'button',
+  className = '',
+  ...rest
+}) {
+  return (
+    <button
+      type={type}
+      disabled={disabled || loading}
+      onClick={onClick}
+      className={`
+        inline-flex items-center gap-1.5 rounded-md border font-medium
+        transition-colors focus:outline-none focus:ring-2 focus:ring-blue-500 focus:ring-offset-1
+        disabled:opacity-50 disabled:cursor-not-allowed
+        ${variants[variant]} ${sizes[size]} ${className}
+      `}
+      {...rest}
+    >
+      {loading && (
+        <svg className="animate-spin h-4 w-4" fill="none" viewBox="0 0 24 24">
+          <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
+          <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8v8z" />
+        </svg>
+      )}
+      {children}
+    </button>
+  );
+}

frontend/src/components/ui/ConfirmDialog.jsx

@@ -0,0 +1,19 @@
+import React from 'react';
+import Modal from './Modal';
+import Button from './Button';
+
+export default function ConfirmDialog({ isOpen, onClose, onConfirm, title, message, loading }) {
+  return (
+    <Modal isOpen={isOpen} onClose={onClose} title={title} size="sm">
+      <p className="text-sm text-gray-600 mb-6">{message}</p>
+      <div className="flex justify-end gap-3">
+        <Button variant="secondary" onClick={onClose} disabled={loading}>
+          Cancel
+        </Button>
+        <Button variant="danger" onClick={onConfirm} loading={loading}>
+          Delete
+        </Button>
+      </div>
+    </Modal>
+  );
+}

frontend/src/components/ui/FormField.jsx

@@ -0,0 +1,58 @@
+import React from 'react';
+
+export default function FormField({ label, name, error, required, children }) {
+  return (
+    <div className="flex flex-col gap-1">
+      <label htmlFor={name} className="text-sm font-medium text-gray-700">
+        {label}
+        {required && <span className="text-red-500 ml-1" aria-hidden="true">*</span>}
+      </label>
+      {children}
+      {error && (
+        <p role="alert" className="text-sm text-red-600">{error}</p>
+      )}
+    </div>
+  );
+}
+
+export function Input({ id, name, type = 'text', value, onChange, placeholder, required, disabled, className = '', ...rest }) {
+  return (
+    <input
+      id={id || name}
+      name={name}
+      type={type}
+      value={value}
+      onChange={onChange}
+      placeholder={placeholder}
+      required={required}
+      disabled={disabled}
+      className={`
+        w-full rounded-md border border-gray-300 px-3 py-2 text-sm
+        focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500
+        disabled:bg-gray-100 disabled:cursor-not-allowed
+        ${className}
+      `}
+      {...rest}
+    />
+  );
+}
+
+export function Textarea({ id, name, value, onChange, placeholder, rows = 3, disabled, className = '' }) {
+  return (
+    <textarea
+      id={id || name}
+      name={name}
+      value={value}
+      onChange={onChange}
+      placeholder={placeholder}
+      rows={rows}
+      disabled={disabled}
+      className={`
+        w-full rounded-md border border-gray-300 px-3 py-2 text-sm
+        focus:outline-none focus:ring-2 focus:ring-blue-500 focus:border-blue-500
+        disabled:bg-gray-100 disabled:cursor-not-allowed resize-y
+        ${className}
+      `}
+    />
+  );
+}

frontend/src/components/ui/Modal.jsx

@@ -0,0 +1,40 @@
+import React, { useEffect } from 'react';
+
+export default function Modal({ isOpen, onClose, title, children, size = 'md' }) {
+  useEffect(() => {
+    if (!isOpen) return;
+    const handleKey = (e) => { if (e.key === 'Escape') onClose(); };
+    document.addEventListener('keydown', handleKey);
+    return () => document.removeEventListener('keydown', handleKey);
+  }, [isOpen, onClose]);
+
+  if (!isOpen) return null;
+
+  const widths = { sm: 'max-w-md', md: 'max-w-lg', lg: 'max-w-2xl', xl: 'max-w-4xl' };
+
+  return (
+    <div
+      className="fixed inset-0 z-50 flex items-center justify-center bg-black/40 backdrop-blur-sm"
+      onClick={(e) => { if (e.target === e.currentTarget) onClose(); }}
+      role="dialog"
+      aria-modal="true"
+      aria-labelledby="modal-title"
+    >
+      <div className={`bg-white rounded-xl shadow-2xl w-full mx-4 ${widths[size]} max-h-[90vh] flex flex-col`}>
+        <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200">
+          <h2 id="modal-title" className="text-lg font-semibold text-gray-900">{title}</h2>
+          <button
+            onClick={onClose}
+            className="text-gray-400 hover:text-gray-600 rounded p-1 transition-colors"
+            aria-label="Close modal"
+          >
+            <svg className="w-5 h-5" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
+            </svg>
+          </button>
+        </div>
+        <div className="p-6 overflow-y-auto flex-1">{children}</div>
+      </div>
+    </div>
+  );
+}

frontend/src/index.css

@@ -0,0 +1,9 @@
+@tailwind base;
+@tailwind components;
+@tailwind utilities;
+
+@layer base {
+  body {
+    @apply bg-gray-50 text-gray-900 antialiased;
+  }
+}

frontend/src/main.jsx

@@ -0,0 +1,13 @@
+import React from 'react';
+import ReactDOM from 'react-dom/client';
+import { BrowserRouter } from 'react-router-dom';
+import App from './App';
+import './index.css';
+
+ReactDOM.createRoot(document.getElementById('root')).render(
+  <React.StrictMode>
+    <BrowserRouter>
+      <App />
+    </BrowserRouter>
+  </React.StrictMode>
+);

frontend/src/pages/AnimalDetail.jsx

@@ -0,0 +1,214 @@
+import React, { useEffect, useState } 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 Alert from '../components/ui/Alert';
+import AuditLogSection from '../components/AuditLogSection';
+
+/** 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];
+}
+
+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(location.state?.template ?? []);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [successMsg, setSuccessMsg] = useState(null);
+
+  const [showAddStatus, setShowAddStatus] = useState(false);
+  const [editStatus, setEditStatus] = useState(null);
+  const [deleteStatus, setDeleteStatus] = useState(null);
+  const [deleteLoading, setDeleteLoading] = useState(false);
+
+  async function load() {
+    setLoading(true);
+    setError(null);
+    try {
+      const [animalData, statusData] = await Promise.all([
+        animalsApi.get(id),
+        dailyStatusesApi.list(id),
+      ]);
+      setAnimal(animalData);
+      setStatuses(statusData);
+
+      // Fetch template if not passed via navigation state
+      if (!location.state?.template) {
+        const tmpl = await experimentsApi.getTemplate(animalData.experiment_id);
+        setTemplate(tmpl);
+      }
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  useEffect(() => { load(); }, [id]);
+
+  function flash(msg) {
+    setSuccessMsg(msg);
+    setTimeout(() => setSuccessMsg(null), 3000);
+  }
+
+  function handleStatusSaved() {
+    setShowAddStatus(false);
+    setEditStatus(null);
+    load();
+    flash(editStatus ? 'Daily status updated.' : 'Daily status logged.');
+  }
+
+  async function handleDeleteStatus() {
+    setDeleteLoading(true);
+    try {
+      await dailyStatusesApi.delete(deleteStatus.id);
+      setDeleteStatus(null);
+      load();
+      flash('Daily status removed.');
+    } catch (err) {
+      setError(err.message);
+      setDeleteStatus(null);
+    } finally {
+      setDeleteLoading(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} />
+      <Button variant="secondary" className="mt-4" onClick={() => navigate(-1)}>← Back</Button>
+    </div>
+  );
+
+  const activeFields = template.filter((f) => f.active);
+
+  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>
+        <span className="mx-2">/</span>
+        <span className="text-gray-900 font-medium">{animal.animal_name}</span>
+      </nav>
+
+      <div className="flex items-start justify-between mb-6">
+        <div>
+          <h1 className="text-2xl font-bold text-gray-900">{animal.animal_name}</h1>
+          <p className="text-sm text-gray-500 mt-0.5">
+            ID: <span className="font-mono">{animal.animal_id_string}</span>
+            {' · '}
+            {statuses.length} daily status {statuses.length !== 1 ? 'entries' : 'entry'}
+          </p>
+        </div>
+        <Button onClick={() => setShowAddStatus(true)}>+ Log Daily Status</Button>
+      </div>
+
+      {successMsg && <Alert type="success" message={successMsg} />}
+      {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
+
+      {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>
+
+              {activeFields.length > 0 ? (
+                <dl className="grid grid-cols-1 sm:grid-cols-2 gap-x-6 gap-y-2 text-sm">
+                  {activeFields
+                    .map((f) => ({ field: f, value: getFieldValue(s, f) }))
+                    .filter(({ value }) => value)
+                    .map(({ field, value }) => (
+                      <div key={field.key} className={field.type === 'textarea' ? 'sm:col-span-2' : ''}>
+                        <dt className="text-xs font-medium text-gray-500 uppercase tracking-wide">{field.label}</dt>
+                        <dd className="text-gray-800 mt-0.5 whitespace-pre-wrap">{value}</dd>
+                      </div>
+                    ))}
+                </dl>
+              ) : null}
+
+              {/* Fallback: show raw builtin fields if template is empty */}
+              {activeFields.length === 0 && (
+                <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}>
+                      <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>
+              )}
+
+              {activeFields.length > 0 &&
+                activeFields.every((f) => !getFieldValue(s, f)) && (
+                  <p className="text-sm text-gray-400 italic">No details recorded for this date.</p>
+                )}
+            </div>
+          ))}
+        </div>
+      )}
+
+      <AuditLogSection tableName="daily_statuses" />
+
+      <Modal isOpen={showAddStatus} onClose={() => setShowAddStatus(false)} title="Log Daily Status" size="lg">
+        <DailyStatusForm
+          animalId={id}
+          template={template}
+          onSuccess={handleStatusSaved}
+          onCancel={() => setShowAddStatus(false)}
+        />
+      </Modal>
+
+      <Modal isOpen={!!editStatus} onClose={() => setEditStatus(null)} title="Edit Daily Status" size="lg">
+        <DailyStatusForm
+          existing={editStatus}
+          animalId={id}
+          template={template}
+          onSuccess={handleStatusSaved}
+          onCancel={() => setEditStatus(null)}
+        />
+      </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') : ''}?`}
+      />
+    </div>
+  );
+}

frontend/src/pages/Dashboard.jsx

@@ -0,0 +1,162 @@
+import React, { useEffect, useState } from 'react';
+import { useNavigate } from 'react-router-dom';
+import { experimentsApi } from '../api/client';
+import Button from '../components/ui/Button';
+import Modal from '../components/ui/Modal';
+import ConfirmDialog from '../components/ui/ConfirmDialog';
+import ExperimentForm from '../components/ExperimentForm';
+import Alert from '../components/ui/Alert';
+import { format } from 'date-fns';
+import AuditLogSection from '../components/AuditLogSection';
+
+export default function Dashboard() {
+  const navigate = useNavigate();
+  const [experiments, setExperiments] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [showCreateModal, setShowCreateModal] = useState(false);
+  const [editTarget, setEditTarget] = useState(null);
+  const [deleteTarget, setDeleteTarget] = useState(null);
+  const [deleteLoading, setDeleteLoading] = useState(false);
+  const [successMsg, setSuccessMsg] = useState(null);
+
+  async function loadExperiments() {
+    setLoading(true);
+    setError(null);
+    try {
+      const data = await experimentsApi.list();
+      setExperiments(data);
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  useEffect(() => { loadExperiments(); }, []);
+
+  function flash(msg) {
+    setSuccessMsg(msg);
+    setTimeout(() => setSuccessMsg(null), 3000);
+  }
+
+  function handleCreated(exp) {
+    setShowCreateModal(false);
+    loadExperiments();
+    flash(`Experiment "${exp.title}" created.`);
+  }
+
+  function handleUpdated(exp) {
+    setEditTarget(null);
+    loadExperiments();
+    flash(`Experiment "${exp.title}" updated.`);
+  }
+
+  async function handleDelete() {
+    setDeleteLoading(true);
+    try {
+      await experimentsApi.delete(deleteTarget.id);
+      setDeleteTarget(null);
+      loadExperiments();
+      flash('Experiment deleted.');
+    } catch (err) {
+      setError(err.message);
+      setDeleteTarget(null);
+    } finally {
+      setDeleteLoading(false);
+    }
+  }
+
+  return (
+    <div className="max-w-5xl mx-auto px-4 py-8">
+      <div className="flex items-center justify-between mb-6">
+        <div>
+          <h1 className="text-2xl font-bold text-gray-900">Experiments</h1>
+          <p className="text-sm text-gray-500 mt-0.5">Manage all animal experimental studies</p>
+        </div>
+        <Button onClick={() => setShowCreateModal(true)}>
+          + New Experiment
+        </Button>
+      </div>
+
+      {successMsg && <Alert type="success" message={successMsg} className="mb-4" />}
+      {error && <Alert type="error" message={error} onDismiss={() => setError(null)} />}
+
+      {loading && (
+        <div className="text-center py-16 text-gray-400" aria-live="polite" aria-busy="true">Loading experiments…</div>
+      )}
+
+      {!loading && experiments.length === 0 && (
+        <div className="text-center py-20 border-2 border-dashed border-gray-200 rounded-xl">
+          <p className="text-gray-400 text-lg mb-2">No experiments yet</p>
+          <p className="text-gray-400 text-sm mb-4">Create your first experiment to get started.</p>
+          <Button onClick={() => setShowCreateModal(true)}>+ New Experiment</Button>
+        </div>
+      )}
+
+      {!loading && experiments.length > 0 && (
+        <div className="grid gap-4">
+          {experiments.map((exp) => (
+            <div
+              key={exp.id}
+              className="bg-white border border-gray-200 rounded-xl p-5 flex items-center justify-between hover:border-blue-300 hover:shadow-sm transition-all cursor-pointer group"
+              onClick={() => navigate(`/experiments/${exp.id}`)}
+            >
+              <div>
+                <h2 className="font-semibold text-gray-900 group-hover:text-blue-700 transition-colors">
+                  {exp.title}
+                </h2>
+                <div className="text-sm text-gray-500 mt-0.5 flex gap-4">
+                  <span>{exp._count?.animals ?? 0} animal{exp._count?.animals !== 1 ? 's' : ''}</span>
+                  <span>Created {format(new Date(exp.created_at), 'MMM d, yyyy')}</span>
+                </div>
+              </div>
+              <div className="flex gap-2" onClick={(e) => e.stopPropagation()}>
+                <Button
+                  size="sm"
+                  variant="secondary"
+                  onClick={() => setEditTarget(exp)}
+                >
+                  Edit
+                </Button>
+                <Button
+                  size="sm"
+                  variant="danger"
+                  onClick={() => setDeleteTarget(exp)}
+                >
+                  Delete
+                </Button>
+              </div>
+            </div>
+          ))}
+        </div>
+      )}
+
+      <AuditLogSection tableName="experiments" />
+
+      {/* Create modal */}
+      <Modal isOpen={showCreateModal} onClose={() => setShowCreateModal(false)} title="New Experiment">
+        <ExperimentForm onSuccess={handleCreated} onCancel={() => setShowCreateModal(false)} />
+      </Modal>
+
+      {/* Edit modal */}
+      <Modal isOpen={!!editTarget} onClose={() => setEditTarget(null)} title="Edit Experiment">
+        <ExperimentForm
+          existing={editTarget}
+          onSuccess={handleUpdated}
+          onCancel={() => setEditTarget(null)}
+        />
+      </Modal>
+
+      {/* Delete confirmation */}
+      <ConfirmDialog
+        isOpen={!!deleteTarget}
+        onClose={() => setDeleteTarget(null)}
+        onConfirm={handleDelete}
+        loading={deleteLoading}
+        title="Delete Experiment"
+        message={`Are you sure you want to delete "${deleteTarget?.title}"? All associated animals and daily statuses will be permanently removed.`}
+      />
+    </div>
+  );
+}

frontend/src/pages/ExperimentDetail.jsx

@@ -0,0 +1,200 @@
+import React, { useEffect, useState } from 'react';
+import { useParams, useNavigate, Link } from 'react-router-dom';
+import { experimentsApi, animalsApi } from '../api/client';
+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';
+
+export default function ExperimentDetail() {
+  const { id } = useParams();
+  const navigate = useNavigate();
+
+  const [experiment, setExperiment] = useState(null);
+  const [animals, setAnimals] = useState([]);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+  const [successMsg, setSuccessMsg] = useState(null);
+
+  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);
+
+  async function load() {
+    setLoading(true);
+    setError(null);
+    try {
+      const [exp, anims] = await Promise.all([
+        experimentsApi.get(id),
+        animalsApi.list(id),
+      ]);
+      setExperiment(exp);
+      setAnimals(anims);
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  }
+
+  useEffect(() => { load(); }, [id]);
+
+  function flash(msg) {
+    setSuccessMsg(msg);
+    setTimeout(() => setSuccessMsg(null), 3000);
+  }
+
+  function handleAnimalSaved(animal) {
+    setShowAddAnimal(false);
+    setEditAnimal(null);
+    load();
+    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" 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} />
+      <Button variant="secondary" className="mt-4" onClick={() => navigate('/')}>← Back</Button>
+    </div>
+  );
+
+  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>
+        <span className="text-gray-900 font-medium">{experiment.title}</span>
+      </nav>
+
+      <div className="flex items-start justify-between mb-6">
+        <div>
+          <h1 className="text-2xl font-bold text-gray-900">{experiment.title}</h1>
+          <p className="text-sm text-gray-500 mt-0.5">
+            {animals.length} animal{animals.length !== 1 ? 's' : ''} enrolled
+          </p>
+        </div>
+        <div className="flex gap-2">
+          <Button variant="secondary" onClick={() => setShowTemplate(true)}>
+            <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor">
+              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2}
+                d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2" />
+            </svg>
+            Record Template
+          </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 summary strip */}
+      {experiment.template && experiment.template.length > 0 && (
+        <div className="mb-5 flex flex-wrap gap-1.5">
+          {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 ${
+                f.active ? 'bg-blue-50 border-blue-200 text-blue-700' : 'bg-gray-100 border-gray-200 text-gray-400'
+              }`}
+            >
+              {f.active ? null : <span title="hidden">◌</span>}
+              {f.label}
+            </span>
+          ))}
+          <button
+            onClick={() => setShowTemplate(true)}
+            className="text-xs text-gray-400 hover:text-blue-600 underline underline-offset-2 transition-colors"
+          >
+            edit
+          </button>
+        </div>
+      )}
+
+      {animals.length === 0 ? (
+        <div className="text-center py-16 border-2 border-dashed border-gray-200 rounded-xl">
+          <p className="text-gray-400 mb-3">No animals enrolled in this experiment yet.</p>
+          <Button onClick={() => setShowAddAnimal(true)}>+ Add First Animal</Button>
+        </div>
+      ) : (
+        <div className="grid gap-3">
+          {animals.map((animal) => (
+            <div
+              key={animal.id}
+              className="bg-white border border-gray-200 rounded-xl p-4 flex items-center justify-between hover:border-blue-300 hover:shadow-sm transition-all cursor-pointer group"
+              onClick={() => navigate(`/animals/${animal.id}`, { state: { template: experiment.template } })}
+            >
+              <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>
+            </div>
+          ))}
+        </div>
+      )}
+
+      <AuditLogSection tableName="animals" />
+
+      {/* Template editor modal */}
+      <Modal isOpen={showTemplate} onClose={() => setShowTemplate(false)} title="Daily Record Template" size="lg">
+        <TemplateEditor experimentId={id} onClose={handleTemplateSaved} />
+      </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} experimentId={id} onSuccess={handleAnimalSaved} onCancel={() => setEditAnimal(null)} />
+      </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

@@ -0,0 +1,19 @@
+/** @type {import('tailwindcss').Config} */
+module.exports = {
+  content: ['./index.html', './src/**/*.{js,jsx}'],
+  theme: {
+    extend: {
+      colors: {
+        brand: {
+          50: '#eff6ff',
+          100: '#dbeafe',
+          500: '#3b82f6',
+          600: '#2563eb',
+          700: '#1d4ed8',
+          900: '#1e3a8a',
+        },
+      },
+    },
+  },
+  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 +1,93 @@
+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(),
+  },
+}));
+
+const ANIMAL_ID = 'animal-001';
+const onSuccess = jest.fn();
+const onCancel = jest.fn();
+
+beforeEach(() => jest.clearAllMocks());
+
+describe('DailyStatusForm', () => {
+  it('renders date field (required) and optional fields', () => {
+    render(<DailyStatusForm animalId={ANIMAL_ID} 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} 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} 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} onSuccess={onSuccess} onCancel={onCancel} />);
+
+    const dateInput = screen.getByLabelText(/date/i);
+    await userEvent.clear(dateInput);
+    await userEvent.type(dateInput, '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}
+        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} onSuccess={onSuccess} onCancel={onCancel} />);
+    fireEvent.click(screen.getByRole('button', { name: /cancel/i }));
+    expect(onCancel).toHaveBeenCalled();
+  });
+});

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/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/setup.js

@@ -0,0 +1 @@
+import '@testing-library/jest-dom';

frontend/vite.config.js

@@ -0,0 +1,22 @@
+import { defineConfig } from 'vite';
+import react from '@vitejs/plugin-react';
+
+export default defineConfig({
+  plugins: [react()],
+  server: {
+    host: '0.0.0.0',
+    port: 5173,
+    proxy: {
+      '/api': {
+        target: process.env.VITE_API_URL || 'http://localhost:3001',
+        changeOrigin: true,
+      },
+    },
+  },
+  test: {
+    globals: true,
+    environment: 'jsdom',
+    setupFiles: ['./tests/setup.js'],
+    css: false,
+  },
+});

memory.md

@@ -123,4 +123,55 @@ All PUT and DELETE routes pass through `auditMiddleware` which:
 - All tests run inside Docker via `docker-compose.test.yml`
 
 ## Red Team Audit
-_To be filled after Phase 3 testing is complete._
+
+### Findings
+
+#### 🔴 Critical
+
+1. **CORS wildcard (`origin: '*'`)** — The backend accepts requests from any origin. An attacker on a different domain could make authenticated browser requests to the API if any auth is added later, or exfiltrate data via CSRF.
+   - **Fix**: Restrict `CORS_ORIGIN` to the frontend's origin in production.
+
+2. **Prisma `migrate deploy` via `execSync` on server start** — Running migrations inline at startup means a crashing migration kills the entire service process. Also, injecting `DATABASE_URL` with special characters could theoretically escape the shell via `child_process.execSync`.
+   - **Fix**: Run migrations as a separate Docker entrypoint step, not inside the Node process.
+
+3. **Unparameterized `table_name` in audit logs route** — `table_name` is accepted as a plain string from query params and passed directly to Prisma. Prisma ORM prevents SQL injection here, but the field is never validated against a known allowlist — an attacker can write arbitrary strings to query params and pollute logs.
+   - **Fix**: Validate `tableName` against an allowlist: `['experiments', 'animals', 'daily_statuses', 'audit_logs']`.
+
+#### 🟡 Medium
+
+4. **No rate limiting** — All API endpoints are open to brute-force or denial-of-service via request flooding. Express has no rate limiter middleware.
+   - **Fix**: Add `express-rate-limit` on all `/api/*` routes.
+
+5. **Helmet defaults only** — `helmet()` is enabled but with defaults; notably `Content-Security-Policy` is not tuned for the SPA. The nginx proxy serves the frontend without explicit CSP headers either.
+   - **Fix**: Add a CSP header in nginx and strengthen helmet config.
+
+6. **Docker: no `read_only` filesystem or user restriction** — The backend and frontend containers run as root by default.
+   - **Fix**: Add `user: node` and `read_only: true` (with tmpfs for writable paths) in `docker-compose.yml`.
+
+7. **Postgres port exposed on host** — `docker-compose.yml` exposes port 5432 externally. In production, only the backend container needs DB access.
+   - **Fix**: Remove host-side port mapping for postgres; use internal Docker networking only.
+
+8. **`NODE_ENV=production` skip for Prisma generate** — `npx prisma generate` is not called in the production Dockerfile before `npm ci --only=production`, so the generated client may be missing.
+   - **Fix**: Run `prisma generate` in the builder stage.
+
+#### 🟢 UX / Low
+
+9. **Audit log section on Dashboard shows ALL experiments audit logs** (no `recordId` filter) — this is intentional but confusing; a large table will render hundreds of rows without pagination controls.
+   - **Fix**: Add pagination controls to `AuditLogSection`.
+
+10. **No loading skeleton on list pages** — a "Loading…" text string isn't accessible; screen readers get no meaningful feedback.
+    - **Fix**: Add `aria-live="polite"` region for loading state.
+
+11. **Form submission does not disable all interactive elements** — While the submit button shows a spinner, the Cancel button remains active and can unmount the form mid-submission, causing a React state update on an unmounted component.
+    - **Fix**: Disable Cancel button while `loading` is true (already done for inputs, extend to Cancel).
+
+### Patches Applied (feature/red-team-fixes)
+- Restricted CORS to env-configurable origin
+- Moved migration out of `startServer()` into Docker entrypoint script
+- Added `tableName` allowlist validation on audit logs route
+- Added `express-rate-limit` (100 req/min per IP on all API routes)
+- Removed exposed postgres port from docker-compose
+- Added `user: node` to backend docker-compose service
+- Fixed Prisma generate in production Dockerfile
+- Disabled Cancel button during form submission
+