diff --git a/.github/workflows/e2e.yml b/.github/workflows/e2e.yml
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+# End-to-end Playwright suite (auth, chat, projects, tabular reviews, workflows).
+#
+# This workflow is what makes the e2e suite a MERGE GATE: it runs on every pull
+# request into a protected branch, boots a full local stack (Supabase + backend
+# API + Next.js web + MinIO object storage), runs Playwright, and fails the check
+# when any spec fails. To have a red run actually BLOCK a merge you must also mark
+# this job "e2e / playwright" as a required status check in branch protection —
+# see docs/e2e-ci.md ("Make it merge-blocking").
+#
+# Required repository secret for a full pass:
+#   ANTHROPIC_API_KEY — the critical-path / chat specs send a message and expect a
+#                       streamed answer, which needs a live model key. Add it under
+#                       Settings > Secrets and variables > Actions. Without it the
+#                       chat specs fail; every other spec runs key-less.
+#
+# The e2e user (e2e@mike.local) is bootstrapped in-job by e2e/auth.setup.ts against
+# the local Supabase admin API, so no E2E_PASSWORD secret is needed — the defaults
+# baked into auth.setup.ts are the single source of truth.
+name: e2e
+
+on:
+  workflow_dispatch:
+  pull_request:
+    # `main` is the destination upstream; `upstream-main` is the fork's mirror of
+    # it, so the suite is exercised on the fork PR and stays correct once merged.
+    branches: [main, upstream-main]
+
+# Don't pile up runs on rapid pushes to the same PR.
+concurrency:
+  group: e2e-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  playwright:
+    timeout-minutes: 30
+    runs-on: ubuntu-latest
+    env:
+      # Defaults match e2e/auth.setup.ts; overriding the password here would break
+      # the valid-login specs, so only the base URL is pinned.
+      PLAYWRIGHT_BASE_URL: http://localhost:3000
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      # Three installs: the root package (Playwright + the e2e tooling), the
+      # backend API, and the Next.js web app. Each carries its own lockfile in
+      # this repo's backend/ + frontend/ layout (no root workspace).
+      - name: Install root (Playwright) deps
+        run: npm ci
+      - name: Install backend deps
+        run: npm ci --prefix backend
+      - name: Install frontend deps
+        run: npm ci --prefix frontend
+
+      # npm ci intermittently skips lightningcss's Linux native optional dep
+      # (npm/cli#4828); without it `next dev` can't compile Tailwind CSS and the
+      # web server never boots, so wait-on times out and every spec fails.
+      - name: Ensure lightningcss native binary
+        run: npm install --no-save lightningcss --prefix frontend
+
+      - name: Install Playwright browsers
+        run: npx playwright install --with-deps chromium
+
+      # Object storage. Three specs upload a document (tabular-review row,
+      # project-folder fixture) and assert the result renders; those uploads go
+      # through backend/src/lib/storage.ts, an S3-compatible client that only
+      # ENABLES when R2_ENDPOINT_URL + R2_ACCESS_KEY_ID + R2_SECRET_ACCESS_KEY are
+      # set (region "auto", forcePathStyle true — MinIO-compatible as written).
+      # With no storage the upload endpoint 5xxs and the row never appears. A
+      # `docker run` (not a `services:` container) is used because the minio image
+      # needs the `server /data` argument the services block can't supply, and we
+      # must create the bucket after the server is healthy.
+      - name: Start MinIO (object storage)
+        run: |
+          docker run -d --name minio -p 9000:9000 \
+            -e MINIO_ROOT_USER=minioadmin \
+            -e MINIO_ROOT_PASSWORD=minioadmin \
+            minio/minio:RELEASE.2025-09-07T16-13-09Z server /data
+          for i in $(seq 1 30); do
+            if curl -sf http://localhost:9000/minio/health/ready >/dev/null; then
+              echo "MinIO ready"; break
+            fi
+            echo "waiting for minio ($i)…"; sleep 2
+          done
+          AWS_ACCESS_KEY_ID=minioadmin \
+          AWS_SECRET_ACCESS_KEY=minioadmin \
+          AWS_DEFAULT_REGION=us-east-1 \
+            aws --endpoint-url http://localhost:9000 s3 mb s3://mike
+          AWS_ACCESS_KEY_ID=minioadmin \
+          AWS_SECRET_ACCESS_KEY=minioadmin \
+          AWS_DEFAULT_REGION=us-east-1 \
+            aws --endpoint-url http://localhost:9000 s3 ls s3://mike
+
+      # Supabase (Auth + Postgres). This layout ships no supabase/ config dir
+      # (the app targets a hosted Supabase project), so we scaffold one with
+      # `supabase init` purely to boot the CLI's local stack, then load the
+      # repository's own fresh-database schema — exactly what the README tells a
+      # human to run on a new database (backend/schema.sql).
+      - name: Start local Supabase
+        uses: supabase/setup-cli@v1
+        with:
+          version: latest
+      - name: Init + start Supabase, load schema
+        run: |
+          supabase init --force --with-vscode-settings=false || supabase init --force
+          supabase start
+          DB_URL=$(supabase status -o json | jq -r '.DB_URL')
+          # README: "For a new Supabase database ... run backend/schema.sql". The
+          # schema file already includes the latest shape, so no migrations are
+          # replayed on a fresh CI database.
+          psql "$DB_URL" -v ON_ERROR_STOP=1 -f backend/schema.sql
+
+      - name: Wire env from Supabase
+        run: |
+          API_URL=$(supabase status -o json | jq -r '.API_URL')
+          ANON_KEY=$(supabase status -o json | jq -r '.ANON_KEY')
+          SERVICE_KEY=$(supabase status -o json | jq -r '.SERVICE_ROLE_KEY')
+          # dotenv is last-wins: start from the committed example (so any key we
+          # don't override keeps a sane placeholder) then append the real values.
+          cp backend/.env.example backend/.env
+          {
+            echo "PORT=3001"
+            echo "FRONTEND_URL=http://localhost:3000"
+            echo "SUPABASE_URL=$API_URL"
+            echo "SUPABASE_SECRET_KEY=$SERVICE_KEY"
+            # Both secrets are consumed lazily by download-token signing and API-key
+            # encryption; supply CI dummies well over any length floor.
+            echo "DOWNLOAD_SIGNING_SECRET=ci-download-signing-secret-0123456789abcdef"
+            echo "USER_API_KEYS_ENCRYPTION_SECRET=ci-user-api-keys-encryption-secret-0123456789abcdef"
+            # The suite drives many writes back-to-back (create folder/workflow/
+            # review, upload, update profile, login); the default per-window caps
+            # trip 429s that surface as flaky timeouts. e2e isn't testing
+            # throttling, so raise every tunable cap above one serial run's needs.
+            echo "RATE_LIMIT_GENERAL_MAX=100000"
+            echo "RATE_LIMIT_CHAT_MAX=100000"
+            echo "RATE_LIMIT_CHAT_CREATE_MAX=100000"
+            echo "RATE_LIMIT_UPLOAD_MAX=100000"
+            echo "RATE_LIMIT_EXPORT_MAX=100000"
+            echo "RATE_LIMIT_DATA_DELETE_MAX=100000"
+            # Point the S3-compatible storage adapter at the MinIO container above.
+            echo "R2_ENDPOINT_URL=http://localhost:9000"
+            echo "R2_ACCESS_KEY_ID=minioadmin"
+            echo "R2_SECRET_ACCESS_KEY=minioadmin"
+            echo "R2_BUCKET_NAME=mike"
+            echo "ANTHROPIC_API_KEY=${{ secrets.ANTHROPIC_API_KEY }}"
+          } >> backend/.env
+          # Frontend reads NEXT_PUBLIC_* at dev-server boot.
+          {
+            echo "NEXT_PUBLIC_SUPABASE_URL=$API_URL"
+            echo "NEXT_PUBLIC_SUPABASE_PUBLISHABLE_DEFAULT_KEY=$ANON_KEY"
+            echo "NEXT_PUBLIC_API_BASE_URL=http://localhost:3001"
+          } > frontend/.env.local
+
+      - name: Start backend API
+        run: npm run dev --prefix backend &
+      - name: Start web
+        run: npm run dev --prefix frontend &
+
+      - name: Wait for servers
+        run: npx wait-on http://localhost:3001/health http://localhost:3000 --timeout 120000
+
+      # playwright.config.ts sets webServer to undefined when CI=true, so the job
+      # is responsible for the servers above; Playwright just drives them.
+      - name: Run Playwright
+        run: npx playwright test
+
+      - uses: actions/upload-artifact@v4
+        if: ${{ !cancelled() }}
+        with:
+          name: playwright-report
+          path: |
+            playwright-report/
+            test-results/
+          retention-days: 14
diff --git a/docs/e2e-ci.md b/docs/e2e-ci.md
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index 00000000..8435df46
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+++ b/docs/e2e-ci.md
@@ -0,0 +1,82 @@
+# End-to-end tests in CI
+
+The Playwright suite (`e2e/`) runs on every pull request through
+`.github/workflows/e2e.yml`. This document covers the one repository secret it
+needs and the **branch-protection step that turns a red run into a blocked
+merge** — the workflow reports pass/fail on its own, but only branch protection
+makes that check *required*.
+
+## What the workflow does
+
+On every `pull_request` targeting `main` (or `upstream-main`, the fork mirror),
+and on manual `workflow_dispatch`, the `e2e / playwright` job:
+
+1. installs the root (Playwright), `backend/`, and `frontend/` dependencies;
+2. boots **MinIO** (S3-compatible object storage — three specs upload documents);
+3. boots **local Supabase** (Auth + Postgres) via the Supabase CLI and loads
+   `backend/schema.sql` — the same fresh-database schema the README tells a human
+   to run;
+4. writes `backend/.env` and `frontend/.env.local` from the live Supabase values;
+5. starts the backend API (`:3001`) and the Next.js web app (`:3000`), waits for
+   both to be healthy;
+6. runs `npx playwright test` and uploads the HTML report + traces as an artifact
+   (`playwright-report`) on both pass and fail.
+
+`e2e/auth.setup.ts` bootstraps the shared test user (`e2e@mike.local`) against
+the local Supabase admin API, so no login secret is needed — the credentials
+baked into that file are the single source of truth.
+
+## Required secret
+
+| Secret | Why | Without it |
+|---|---|---|
+| `ANTHROPIC_API_KEY` | The critical-path / chat specs send a message and assert a **streamed** answer, which needs a live model key. | Those chat specs fail; every other spec still runs. |
+
+Add it under **Settings → Secrets and variables → Actions → New repository
+secret**. For pull requests opened from a **fork**, GitHub withholds secrets by
+default — a maintainer approves the run (or re-runs from the branch) so the key
+is available. Treat that approval as the point where the chat specs become
+enforceable for external contributions.
+
+## Make it merge-blocking
+
+The workflow failing is not enough on its own — GitHub will still allow the merge
+unless the check is **required**. Enable branch protection once you have seen the
+suite go green a few times (it is environment-sensitive by nature):
+
+1. **Settings → Branches → Add branch protection rule** (or edit the rule for
+   `main`).
+2. Enable **Require status checks to pass before merging**.
+3. Enable **Require branches to be up to date before merging**.
+4. In the checks search box add **`e2e / playwright`** (the job appears in the
+   list after it has run at least once on a PR).
+5. Recommended alongside it: the unit/build check `backend` and the `license/cla`
+   check.
+6. Save. From now on a red e2e run blocks the **Merge** button.
+
+Equivalent via the GitHub CLI (repo admin token required):
+
+```bash
+gh api -X PUT repos/OWNER/REPO/branches/main/protection \
+  -H "Accept: application/vnd.github+json" \
+  -f 'required_status_checks[strict]=true' \
+  -f 'required_status_checks[contexts][]=e2e / playwright' \
+  -f 'enforce_admins=true' \
+  -f 'required_pull_request_reviews[required_approving_review_count]=1' \
+  -f 'restrictions='
+```
+
+## Running the suite locally
+
+Locally, `playwright.config.ts` starts the backend and web dev servers for you
+(`webServer` is only disabled when `CI=true`), so a full local stack plus:
+
+```bash
+npm ci
+npx playwright install --with-deps chromium
+npm run test:e2e            # or test:e2e:ui / test:e2e:headed
+```
+
+`e2e/auth.setup.ts` reads `SUPABASE_URL` / `SUPABASE_SECRET_KEY` from the
+environment or `backend/.env`, so a running local Supabase + a populated
+`backend/.env` is all the setup needs.