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docs/relaunch-brief.md

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+# CommunityRule relaunch
+
+A short high-level summary of what's being built, what it replaces, and
+how the cutover will work.
+
+## What gets replaced
+
+The existing `CommunityRule` Cloudron app currently hosts three things in
+one container:
+
+- The static marketing site.
+- The Express + MySQL backend (rule drafting, publishing, OTP sign-in).
+- A Flask chatbot.
+
+All three retire together when the new app goes live. The chatbot is
+**not** being migrated or replaced in this stage.
+
+## What the new app is
+
+- A Next.js application with a Postgres database, packaged as a
+  Cloudron app (Docker image + `CloudronManifest.json`).
+- Uses Cloudron's **postgresql + sendmail + localstorage** addons.
+  Cloudron's built-in container supervisor keeps it running.
+- Sign-in changes from 4-digit email **codes** to email **links**
+  ("magic link" authentication). Users click a link in their inbox
+  instead of typing a code.
+- One visible process, one port (3000), one health check
+  (`/api/health`), ~512 MiB memory — the same footprint as the
+  existing app.
+
+## What does NOT carry over
+
+- **No user accounts.** New sign-ins start fresh.
+- **No published rules from the old database.** We'll count the
+  existing `rules` table before cutover and decide whether to publish
+  a read-only archive (CSV/JSON) somewhere for anyone looking for
+  their old work.
+- **No chatbot.**
+
+## How the cutover will work
+
+Side-by-side, the legacy app keeps running untouched
+until the new one is verified.
+
+1. **Staging phase.** New app installed at
+   `staging.communityrule.info` (auto-provisioned by Cloudron). Legacy
+   app at the apex is not touched. Quiet testing within MEDLab/stakeholders.
+2. **Cutover phase.** When staging is green and we're ready, schedule
+   a low-traffic window. During the window (roughly 5–15 minutes of
+   apex downtime):
+   - Take a final backup of the legacy app (Cloudron one-click).
+   - Pull a copy of the legacy `rules` table if we decided to publish
+     an archive.
+   - Uninstall the legacy app at the apex `communityrule.info`.
+   - Move the new app to the apex.
+   - Smoke-test, confirm backups are on, done.
+3. **Post-cutover.** Legacy backup retained ≥ 90 days as a safety net.
+   Legacy source repos get README pointers to the new app and are archived.
+
+Rollback plan during the window: restore the legacy backup to a scratch
+Cloudron slot and point DNS back. Realistic only if we discover
+something genuinely broken in the first few minutes.
+
+## Rough timeline
+
+Roughly this order:
+
+1. **Code prep** — small local change so the app reads Cloudron's
+   injected `CLOUDRON_*` env vars natively. No infra impact.
+2. **Build and push the app image** to a container registry.
+3. **Install at staging** subdomain, smoke test, soft launch.
+4. **Apex cutover window** — the brief downtime above.
+5. **Uninstall legacy**, archive legacy repos.
+6. **Write the steady-state runbook** based on what actually worked.
+
+Staging should be ready to deploy in 1-2 weeks, and we can go from there.