Infra: split dev and production (releases, services, deploy script)

- Production now runs from ~/freezmo-prod/current (release symlink) as a standalone server on :3207; releases are exported by scripts/deploy.sh, built and e2e-verified on a temp port, switched atomically, health- checked via the new /api/healthz (commit + build time) and rolled back automatically on failure. Last 5 releases kept; scripts/rollback.sh for manual rollback. Shared env + data live in ~/freezmo-prod/shared/ and are symlinked into every release (existing sync/push data migrated and verified identical). - Dev runs from ~/freezmo via freezmo-dev.service: next dev on :3217 (LAN only), its own build folder (.next-dev via NEXT_DIST_DIR), its own data (~/freezmo/.freezmo-dev), DEV badge, dev favicon/theme colour, "Freezmo Dev" PWA identity and never the production service worker. - /api/healthz + the Settings Details version row (short commit + build time). output: standalone in next.config (next start still works). - AGENTS.md documents the workflow rules: only dev updates during a task, temporary dirs/ports for test builds, and deploy-at-the-end as the only production path. README gains an Environments and deploy section. - Fix found by the rehearsal: lib/dev-mode.ts must not be a client module (a server component importing a constant from a "use client" module gets a truthy proxy, which baked dev metadata into production builds). - SW -> freezmo-v34.
2026-10-11 19:25:29 +00:00 · 2026-10-11 19:25:29 +00:00 · 3f52ab47c2
commit 3f52ab47c2
parent 5ca0de920c
22 changed files with 665 additions and 35 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@ -0,0 +1,56 @@
+# AGENTS.md — working rules for this repo
+
+Freezmo has two environments. Every session — human or agent — follows these
+rules. They are not optional: production is the app the user actually uses.
+
+## Environments
+
+| | Dev (this working tree) | Production |
+| --- | --- | --- |
+| Path | `~/freezmo` (where you edit) | `~/freezmo-prod/current` (release symlink) |
+| Service | `freezmo-dev.service` | `freezmo.service` |
+| Port | **3217** (`http://<lan-ip>:3217`, LAN only) | **3207** + the public URL |
+| Build folder | `.next-dev` (hot reload) | `.next/standalone` inside the release |
+| Data | `~/freezmo/.freezmo-dev/` | `~/freezmo-prod/shared/freezmo/` |
+| Env | `~/freezmo/.env.local` | `~/freezmo-prod/shared/env.local` |
+| Identity | DEV badge, dev favicon/theme, "Freezmo Dev" PWA | normal |
+
+Dev runs `next dev` with hot reload; **all live, real-time changes go there**.
+Production only ever runs a pushed, verified commit deployed by
+`scripts/deploy.sh` (releases under `~/freezmo-prod/releases/`, last 5 kept,
+`scripts/rollback.sh` to go back).
+
+## Rules
+
+1. **During a task, only the dev instance updates.** Never restart or rebuild
+   production mid-task; production changes only through `scripts/deploy.sh` at
+   the very end.
+2. **Never build into a running instance's folder.** The dev service owns
+   `.next-dev`; `npm run build` (used by the test suites' spawned instances)
+   owns `.next`; a release build owns its own release directory. Any build or
+   test that needs a production build uses a temporary directory and port.
+3. **At the end of a task**: run `npm run lint`, `npm run test:e2e` and
+   `npm run build`, bump the service-worker cache (`public/sw.js`), update the
+   README, commit, push to `main`, then run `scripts/deploy.sh`. Production
+   only ever runs a pushed, verified commit.
+4. **`scripts/deploy.sh` is the only deploy path.** It refuses a dirty tree,
+   refuses commits that aren't on `origin/main`, runs lint + build + the full
+   e2e suite against the new release on a temporary port, switches the
+   `current` symlink atomically, health-checks `/api/healthz` for the new
+   commit and rolls back automatically on failure.
+5. **The Ollama API key never leaves the browser.** It must never appear in
+   exports, sync payloads, share links, logs, URLs, `.env` files committed to
+   the repo, or release directories. Server data (sync blobs, push
+   subscriptions) lives only under `shared/`.
+6. **Both languages, always.** Every user-facing string goes into
+   `lib/i18n-dict.ts` in **en and cs** (the i18n test enforces key parity).
+7. **Phones are first-class**: ≤639px layouts, 44px touch targets, 16px
+   inputs, safe-area padding; verify at 360px and 390px as well as desktop.
+8. **Versioned storage, never lose data.** Deck/homework/chat schemas are
+   validated with zod on read; backups and sync share the same payload schema.
+9. **The test suites live in `tests/`** (`npm run test:e2e`, filterable:
+   `npm run test:e2e -- chat`). Add or extend a suite for every feature; a
+   green suite set is part of "done". Diagnostics that are not gates:
+   `tests/bubble-perf.mjs`, `tests/model-compare.mjs`.
+10. **Keep the service worker honest**: bump `CACHE_VERSION` in `public/sw.js`
+    for every user-visible deploy (the deploy itself does not do this).
--- a/README.md
+++ b/README.md
@ -25,6 +25,7 @@ no database, no data leaving your machine except the requests you send to Ollama
  - [Checking the connection](#checking-the-connection)
 - [Running on your network / from your phone](#running-on-your-network--from-your-phone)
  - [Keep it running as a service](#keep-it-running-as-a-service-systemd-user-service)
+- [Environments and deploy](#environments-and-deploy)
 - [Folders](#folders)
 - [Install as an app (PWA)](#install-as-an-app-pwa)
 - [Security notes](#security-notes)
@ -494,37 +495,90 @@ Notes for phones:
 - Clipboard paste works best on desktop; on mobile use the camera or photo picker.
 - Add the page to your home screen for a full-screen, app-like experience.

-### Keep it running as a service (systemd user service)
+### Keep it running as a service (systemd user services)

-`deploy/freezmo.service` runs the production build under **systemd (user)**, so Freezmo comes back by
-itself after a reboot and restarts if it ever crashes:
+Two units keep Freezmo alive — **production** (`deploy/freezmo.service`, the
+release on :3207) and **dev** (`deploy/freezmo-dev.service`, hot reload on
+:3217). Both come back after a reboot and restart if they crash:

 ```bash
-npm run build                                 # the service serves the built app
 mkdir -p ~/.config/systemd/user
-cp deploy/freezmo.service ~/.config/systemd/user/
+cp deploy/freezmo.service deploy/freezmo-dev.service ~/.config/systemd/user/
 systemctl --user daemon-reload
-systemctl --user enable --now freezmo.service
+systemctl --user enable --now freezmo.service freezmo-dev.service
 loginctl enable-linger "$USER"                # start at boot without logging in
 ```

 | Command | What it does |
 | --- | --- |
-| `systemctl --user status freezmo` | is it up? |
-| `journalctl --user -u freezmo -f` | live logs |
-| `systemctl --user restart freezmo` | after a rebuild |
-| `systemctl --user stop freezmo` | stop it |
+| `systemctl --user status freezmo freezmo-dev` | are they up? |
+| `journalctl --user -u freezmo-dev -f` | live dev logs (hot reload included) |
+| `journalctl --user -u freezmo -f` | live production logs |
+| `systemctl --user restart freezmo-dev` | after changing the dev unit |

-It binds `0.0.0.0:3207` exactly like `npm start` and reads `.env.local` from the project directory.
-The unit refuses to start without `.next/BUILD_ID`, so run `npm run build` before enabling it — and
-again after pulling changes.
+Production is **never** rebuilt or restarted by hand — `scripts/deploy.sh`
+does that, and only with a pushed, verified commit. The dev instance reads
+`~/freezmo/.env.local`, builds into `.next-dev` and keeps its data in
+`.freezmo-dev/`, so nothing it does can touch production. See
+[Environments and deploy](#environments-and-deploy) and
+[AGENTS.md](AGENTS.md) for the rules.

-Because the build and the running server share `.next/`, stop the service before a manual rebuild:
+---
+
+## Environments and deploy
+
+Freezmo runs as two separate instances so that live work never touches what
+you actually use:
+
+| | **Dev** | **Production** |
+| --- | --- | --- |
+| Path | `~/freezmo` (the working tree) | `~/freezmo-prod/current` → `releases/<timestamp>-<sha>` |
+| Service | `freezmo-dev.service` | `freezmo.service` |
+| Port | **3217** — LAN only, hot reload | **3207** — the public URL |
+| Build | `.next-dev` (dev server) | standalone server inside the release |
+| Data | `~/freezmo/.freezmo-dev/` | `~/freezmo-prod/shared/freezmo/` (sync, push) |
+| Env | `~/freezmo/.env.local` | `~/freezmo-prod/shared/env.local` |
+| Look | DEV badge, dev favicon/theme, installs as **Freezmo Dev** | normal |
+
+On your phone: **dev = `http://<lan-ip>:3217`**, production =
+`http://<lan-ip>:3207` (and the public URL). The dev instance is bound to the
+LAN only — nothing routes port 3217 through the public proxy — so source maps
+and the HMR socket never leave the network. It uses a different origin, which
+means separate storage and a separate service worker: the production worker is
+never registered there and both PWAs can be installed side by side.
+
+`NEXT_DIST_DIR` keeps the build folders apart (dev uses `.next-dev`, a plain
+`npm run build` keeps producing `.next` for the test suites), so no build can
+clobber a running server.
+
+### Deploying

 ```bash
-systemctl --user stop freezmo && npm run build && systemctl --user start freezmo
+scripts/deploy.sh                  # deploy the latest origin/main
+scripts/deploy.sh <commit>         # a specific pushed commit
+scripts/deploy.sh --skip-tests     # fast path (lint + build only)
+scripts/rollback.sh                # back to the previous release
 ```

+`deploy.sh` refuses a dirty working tree and commits that aren't on
+`origin/main`, exports the commit into a fresh release directory, runs
+`npm ci`, lint and the production build there, starts the new release on a
+temporary port and runs the **full browser suite against it** (the running
+production is untouched), then links the shared env + data, writes
+`release.json`, flips the `current` symlink atomically, restarts the service
+and polls `/api/healthz` until the new commit answers. Any failure after the
+switch rolls back to the previous release automatically. The last 5 releases
+are kept. The running version (short commit + build time) is shown in
+Settings → Details.
+
+Data that must survive deploys lives in `~/freezmo-prod/shared/`:
+`env.local`, and `freezmo/{sync,push}` (symlinked into every release as
+`.env.local` and `.freezmo`).
+
+The day-to-day rules — only dev updates during a task, production changes only
+through the deploy script at the end — are written down in
+[AGENTS.md](AGENTS.md) so every future session follows them.
+
 ---

 ## Folders
--- a/app/api/healthz/route.ts
+++ b/app/api/healthz/route.ts
@ -0,0 +1,37 @@
+import { readFileSync } from "node:fs";
+import path from "node:path";
+
+export const runtime = "nodejs";
+export const dynamic = "force-dynamic";
+
+/**
+ * Deploy health check: reports which release is running. The deploy script
+ * writes `release.json` next to the server (in the standalone root) and polls
+ * this route after switching `current`; a mismatch or an unreachable server
+ * triggers the automatic rollback.
+ *
+ * In a dev checkout there is no release.json — the route answers with the
+ * commit baked into the environment, or "dev".
+ */
+export async function GET() {
+  let release: { commit?: string; short?: string; builtAt?: string; release?: string } | null = null;
+  try {
+    release = JSON.parse(readFileSync(path.join(process.cwd(), "release.json"), "utf8"));
+  } catch {
+    release = null;
+  }
+
+  const commit = release?.commit ?? process.env.FREEZMO_COMMIT ?? "dev";
+  return Response.json(
+    {
+      ok: true,
+      commit,
+      short: release?.short ?? commit.slice(0, 7),
+      builtAt: release?.builtAt ?? null,
+      release: release?.release ?? null,
+      dev: commit === "dev",
+      uptimeSeconds: Math.round(process.uptime()),
+    },
+    { headers: { "Cache-Control": "no-store" } },
+  );
+}
--- a/app/layout.tsx
+++ b/app/layout.tsx
@ -5,6 +5,9 @@ import { InstallSheet } from "@/components/InstallSheet";
 import { OfflineBanner } from "@/components/OfflineBanner";
 import { ServiceWorkerRegistrar } from "@/components/ServiceWorkerRegistrar";
 import { Toaster } from "@/components/Toaster";
+import { IS_DEV_INSTANCE } from "@/lib/dev-mode";
+
+const devInstanceJs = IS_DEV_INSTANCE ? "true" : "false";
 import "./globals.css";

 export const metadata: Metadata = {
@ -33,7 +36,12 @@ export const metadata: Metadata = {
      { url: "/icons/splash-1668x2388.png", media: "(device-width: 834px) and (device-height: 1194px) and (-webkit-device-pixel-ratio: 2)" },
    ],
  },
-  icons: {
+  icons: IS_DEV_INSTANCE
+    ? {
+        // Dev wears its own favicon so the two instances are never confused.
+        icon: [{ url: "/icons/dev-favicon.svg", type: "image/svg+xml" }],
+      }
+    : {
    icon: [
      // ?v=2 busts browser favicon caches after the icon redesign.
      { url: "/icons/favicon-32.png?v=2", sizes: "32x32", type: "image/png" },
@ -62,10 +70,12 @@ export const viewport: Viewport = {
  // font-size rule in globals.css stops iOS Safari's focus auto-zoom, which
  // ignores the viewport meta anyway.
  viewportFit: "cover",
-  themeColor: [
-    { media: "(prefers-color-scheme: light)", color: "#f4f7fd" },
-    { media: "(prefers-color-scheme: dark)", color: "#0e1424" },
-  ],
+  themeColor: IS_DEV_INSTANCE
+    ? [{ media: "(prefers-color-scheme: light)", color: "#b45309" }, { media: "(prefers-color-scheme: dark)", color: "#b45309" }]
+    : [
+        { media: "(prefers-color-scheme: light)", color: "#f4f7fd" },
+        { media: "(prefers-color-scheme: dark)", color: "#0e1424" },
+      ],
 };

 /**
@ -73,7 +83,7 @@ export const viewport: Viewport = {
 * `theme-color` meta in step with the *app* theme (the SSR metas follow the
 * OS preference, which is wrong once the user has picked a theme here).
 */
-const themeScript = `(function(){try{var s=localStorage.getItem('freezmo.theme');var d=s?s==='dark':window.matchMedia('(prefers-color-scheme: dark)').matches;if(d)document.documentElement.classList.add('dark');var l=localStorage.getItem('freezmo.locale.v1');if(l==='cs'||l==='en')document.documentElement.lang=l;var m=document.querySelector('meta[name="theme-color"][data-app]');if(!m){m=document.createElement('meta');m.setAttribute('name','theme-color');m.setAttribute('data-app','1');document.head.insertBefore(m,document.head.firstChild);}m.setAttribute('content',d?'#0e1424':'#f4f7fd');}catch(e){}})();`;
+const themeScript = `(function(){try{var DEV=${devInstanceJs};var s=localStorage.getItem('freezmo.theme');var d=s?s==='dark':window.matchMedia('(prefers-color-scheme: dark)').matches;if(d)document.documentElement.classList.add('dark');var l=localStorage.getItem('freezmo.locale.v1');if(l==='cs'||l==='en')document.documentElement.lang=l;var m=document.querySelector('meta[name="theme-color"][data-app]');if(!m){m=document.createElement('meta');m.setAttribute('name','theme-color');m.setAttribute('data-app','1');document.head.insertBefore(m,document.head.firstChild);}m.setAttribute('content',DEV?'#b45309':(d?'#0e1424':'#f4f7fd'));}catch(e){}})();`;

 /**
 * Captures Chrome's `beforeinstallprompt` (it can fire before React hydrates)
--- a/app/manifest.ts
+++ b/app/manifest.ts
@ -4,7 +4,35 @@ import type { MetadataRoute } from "next";
 * Web app manifest — what makes Freezmo installable on iOS/Android
 * (iOS reads the apple-* meta tags in app/layout.tsx as well).
 */
+const devInstance = process.env.NEXT_PUBLIC_FREEZMO_DEV === "1";
+
 export default function manifest(): MetadataRoute.Manifest {
+  if (devInstance) {
+    return {
+      // A distinct identity so the dev PWA installs next to the real one.
+      id: "/dev",
+      name: "Freezmo Dev — notes to study feed",
+      short_name: "Freezmo Dev",
+      description: "Development instance of Freezmo (hot reload). Not the production app.",
+      start_url: "/",
+      scope: "/",
+      display: "standalone",
+      display_override: ["standalone", "minimal-ui"],
+      orientation: "portrait",
+      background_color: "#1c1917",
+      theme_color: "#b45309",
+      categories: ["education", "productivity"],
+      icons: [
+        { src: "/icons/dev-icon.svg", sizes: "any", type: "image/svg+xml", purpose: "any" },
+        { src: "/icons/icon-512.png", sizes: "512x512", type: "image/png", purpose: "any" },
+      ],
+      shortcuts: [
+        { name: "New deck", short_name: "New", url: "/create" },
+        { name: "Library", short_name: "Library", url: "/" },
+      ],
+    };
+  }
+
  return {
    id: "/",
    name: "Freezmo — notes to study feed",
--- a/components/AppHeader.tsx
+++ b/components/AppHeader.tsx
@ -6,6 +6,7 @@ import { useEffect, useState } from "react";
 import { SettingsDialog } from "@/components/SettingsDialog";
 import { TabBar } from "@/components/TabBar";
 import { ThemeToggle } from "@/components/ThemeToggle";
+import { IS_DEV_INSTANCE } from "@/lib/dev-mode";
 import { useI18n } from "@/lib/i18n";
 import { OPEN_SETTINGS_EVENT } from "@/lib/ui-events";
 import { cn } from "@/lib/utils";
@ -61,6 +62,11 @@ export function AppHeader({ className, compact = false }: { className?: string;
            />
            <span className="flex min-w-0 items-baseline gap-2">
              <span className="text-[15px] font-semibold tracking-[-0.01em] text-[var(--text)]">Freezmo</span>
+              {IS_DEV_INSTANCE ? (
+                <span className="rounded-md border border-amber-400/60 bg-amber-400/15 px-1.5 py-0.5 text-[10px] font-bold uppercase tracking-wide text-amber-700 dark:text-amber-300">
+                  DEV
+                </span>
+              ) : null}
              {!compact ? (
                <span className="hidden truncate text-[13px] text-[var(--text-subtle)] sm:inline">
                  {t("header.tagline")}
--- a/components/ServiceWorkerRegistrar.tsx
+++ b/components/ServiceWorkerRegistrar.tsx
@ -2,6 +2,8 @@

 import { useEffect } from "react";

+import { IS_DEV_INSTANCE } from "@/lib/dev-mode";
+
 /**
 * Registers the service worker in production builds only.
 *
@ -11,6 +13,8 @@ import { useEffect } from "react";
 export function ServiceWorkerRegistrar() {
  useEffect(() => {
    if (process.env.NODE_ENV !== "production") return;
+    // A dev instance never registers the production worker, whatever the build.
+    if (IS_DEV_INSTANCE) return;
    if (typeof navigator === "undefined" || !("serviceWorker" in navigator)) return;

    const register = () => {
--- a/components/SettingsDialog.tsx
+++ b/components/SettingsDialog.tsx
@ -4,6 +4,7 @@ import { AnimatePresence, motion, useDragControls, useReducedMotion } from "fram
 import { useEffect, useRef, useState, useSyncExternalStore } from "react";

 import { LOCALES, useI18n, type Locale } from "@/lib/i18n";
+import { useVersion } from "@/lib/use-version";
 import { haptic } from "@/lib/haptics";
 import { modelErrorCopy } from "@/lib/model-errors";
 import { springSheet } from "@/lib/motion";
@ -53,6 +54,7 @@ export function SettingsDialog({
  const { health, loading, error, refresh, apiKey, checkedAt } = useHealth();
  const installAvailable = useInstallAvailable();
  const { locale, setLocale, t, plural } = useI18n();
+  const version = useVersion();
  const keyInputRef = useRef<HTMLInputElement>(null);
  const settings = useSyncExternalStore(
    settingsStore.subscribe,
@ -513,6 +515,17 @@ export function SettingsDialog({
                            mono
                            badge={modelBadge(health?.text)}
                          />
+                          {version ? (
+                            <DetailRow
+                              label={t("settings.version")}
+                              value={
+                                version.builtAt
+                                  ? `${version.short} · ${new Date(version.builtAt).toLocaleString()}`
+                                  : version.short
+                              }
+                              mono
+                            />
+                          ) : null}
                        </dl>
                        {health?.mode === "direct-cloud" && health.needsKey ? (
                          <p className="pt-2 text-[11px] leading-relaxed text-[var(--text-subtle)]">
@ -782,6 +795,12 @@ export function SettingsDialog({
                ) : null}

                {health ? <HealthPanel health={health} /> : null}
+                {version ? (
+                  <p className="mt-2 text-[11px] text-[var(--text-subtle)]">
+                    {t("settings.version")}: <span className="font-mono">{version.short}</span>
+                    {version.builtAt ? ` · ${new Date(version.builtAt).toLocaleString()}` : ""}
+                  </p>
+                ) : null}

                {/* keeps real content out of the 36px fade strip at the bottom */}
                <div className="h-9" aria-hidden />
--- a/components/Sidebar.tsx
+++ b/components/Sidebar.tsx
@ -20,6 +20,7 @@ import {
 import { useTheme } from "@/components/ThemeToggle";
 import { createFolder, folderStore } from "@/lib/folders";
 import { haptic } from "@/lib/haptics";
+import { IS_DEV_INSTANCE } from "@/lib/dev-mode";
 import { useI18n } from "@/lib/i18n";
 import { ALL_FOLDERS, folderSelection, useSelectedFolder } from "@/lib/nav";
 import { UNORGANIZED_ID } from "@/lib/schemas";
@ -102,7 +103,14 @@ function NavContent({ collapsed = false }: { collapsed?: boolean }) {
            className="size-7 shrink-0 rounded-lg shadow-[0_1px_3px_rgb(14_21_40/0.35)]"
          />
          {!collapsed ? (
-            <span className="text-[15px] font-semibold tracking-[-0.01em] text-[var(--text)]">Freezmo</span>
+            <>
+              <span className="text-[15px] font-semibold tracking-[-0.01em] text-[var(--text)]">Freezmo</span>
+              {IS_DEV_INSTANCE ? (
+                <span className="rounded-md border border-amber-400/60 bg-amber-400/15 px-1.5 py-0.5 text-[10px] font-bold uppercase tracking-wide text-amber-700 dark:text-amber-300">
+                  DEV
+                </span>
+              ) : null}
+            </>
          ) : null}
        </Link>
        {!collapsed ? (
--- a/deploy/freezmo-dev.service
+++ b/deploy/freezmo-dev.service
@ -0,0 +1,40 @@
+[Unit]
+# Freezmo — dev instance (hot reload, LAN only).
+#
+# This is the working tree (~/freezmo). Everything live happens here: edits are
+# visible within seconds, its build folder is .next-dev (a production build can
+# never clobber it) and its data lives in ~/freezmo/.freezmo-dev, so test
+# shares, sync blobs and rate limits never touch production data.
+#
+# It binds the LAN so the phone can reach it, but nothing routes this port
+# through the public proxy — production stays the only public instance.
+# It shows a DEV badge, uses a dev favicon/theme colour, installs as
+# "Freezmo Dev" (separate origin, separate storage) and never registers the
+# production service worker.
+#
+# Install (per user, no root needed):
+#   cp ~/freezmo/deploy/freezmo-dev.service ~/.config/systemd/user/
+#   systemctl --user daemon-reload
+#   systemctl --user enable --now freezmo-dev.service
+# Logs:  journalctl --user -u freezmo-dev -f
+Description=Freezmo dev instance (hot reload, LAN only)
+Documentation=file://%h/freezmo/README.md
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=simple
+WorkingDirectory=%h/freezmo
+Environment=NEXT_TELEMETRY_DISABLED=1
+Environment=NEXT_DIST_DIR=.next-dev
+Environment=NEXT_PUBLIC_FREEZMO_DEV=1
+Environment=SYNC_DIR=%h/freezmo/.freezmo-dev/sync
+Environment=PUSH_DIR=%h/freezmo/.freezmo-dev/push
+Environment=PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+ExecStart=/bin/node %h/freezmo/node_modules/next/dist/bin/next dev -H 0.0.0.0 -p 3217
+Restart=always
+RestartSec=2
+TimeoutStartSec=0
+
+[Install]
+WantedBy=default.target
--- a/deploy/freezmo.service
+++ b/deploy/freezmo.service
@ -1,13 +1,21 @@
 [Unit]
-# Freezmo — self-hosted notes-to-study-feed app.
+# Freezmo — production release (self-hosted study app).
+#
+# Runs the "current" release symlink: scripts/deploy.sh atomically flips it and
+# restarts this unit, so production only ever runs a pushed, verified commit.
+# Layout: ~/freezmo-prod/{releases/<name>,current -> releases/<name>,shared}
+#   current/server/server.js   standalone Next server (built by the deploy)
+#   current/server/.env.local  -> shared/env.local
+#   current/server/.freezmo    -> shared/freezmo   (sync/, push/)
+#
 # Install (per user, no root needed):
 #   mkdir -p ~/.config/systemd/user
-#   cp deploy/freezmo.service ~/.config/systemd/user/
+#   cp ~/freezmo/deploy/freezmo.service ~/.config/systemd/user/
 #   systemctl --user daemon-reload
 #   systemctl --user enable --now freezmo.service
 #   loginctl enable-linger "$USER"     # start at boot without logging in
 # Logs:  journalctl --user -u freezmo -f
-Description=Freezmo (self-hosted study app)
+Description=Freezmo (self-hosted study app, production)
 Documentation=file://%h/freezmo/README.md
 After=network-online.target
 Wants=network-online.target
@ -16,15 +24,19 @@ After=ollama.service

 [Service]
 Type=simple
-WorkingDirectory=%h/freezmo
+# The standalone server keeps its own cwd; the release carries shared env/data
+# as symlinks, and EnvironmentFile is the belt to that pair of braces.
+WorkingDirectory=%h/freezmo-prod/current/server
 Environment=NODE_ENV=production
 Environment=NEXT_TELEMETRY_DISABLED=1
+Environment=PORT=3207
+Environment=HOSTNAME=0.0.0.0
 Environment=PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
-# Refuse to start without a production build — clearer than next crashing in a
-# restart loop. Run `npm run build` in %h/freezmo first.
-AssertPathExists=%h/freezmo/.next/BUILD_ID
-# Next.js loads .env.local (OLLAMA_*) from the working directory itself.
-ExecStart=/bin/node %h/freezmo/node_modules/next/dist/bin/next start -H 0.0.0.0 -p 3207
+EnvironmentFile=-%h/freezmo-prod/shared/env.local
+# Refuse to start without a release — clearer than next crashing in a restart
+# loop. Run scripts/deploy.sh (from %h/freezmo) first.
+AssertPathExists=%h/freezmo-prod/current/server/server.js
+ExecStart=/bin/node %h/freezmo-prod/current/server/server.js
 Restart=always
 RestartSec=3
 TimeoutStartSec=0
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@ -15,11 +15,15 @@ const eslintConfig = [
    ignores: [
      "node_modules/**",
      ".next/**",
+      // The dev service's build folder (NEXT_DIST_DIR).
+      ".next-dev/**",
      "out/**",
      "build/**",
      "next-env.d.ts",
      // Generated at build/dev time by scripts/copy-pdf-worker.mjs.
      "public/pdf.worker.min.mjs",
+      // Test scratch: rehearsal standalone copies carry a full node_modules.
+      "tests/.tmp/**",
    ],
  },
 ];
--- a/lib/dev-mode.ts
+++ b/lib/dev-mode.ts
@ -0,0 +1,7 @@
+/**
+ * True when this build is the development instance (`freezmo-dev.service`
+ * sets NEXT_PUBLIC_FREEZMO_DEV=1). Baked in at build/start time, so the dev
+ * server shows its badge, favicon, theme colour and PWA identity while a
+ * production build is completely unaffected.
+ */
+export const IS_DEV_INSTANCE = process.env.NEXT_PUBLIC_FREEZMO_DEV === "1";
--- a/lib/i18n-dict.ts
+++ b/lib/i18n-dict.ts
@ -987,6 +987,7 @@ const en: Record<string, string> = {
  "chat.savedToNotes": "Saved to {deck}'s notes",
  "chat.savedToNotesTrimmed": "Saved to {deck}'s notes (trimmed to fit)",
  "chat.savedFromChat": "Saved from chat",
+  "settings.version": "Version",
  "settings.chatNotes": "Keep notes text for chat",
  "settings.chatNotesNote": "Chat answers from the notes you added (stored with each deck). Turn off to use only the generated study content.",
  "server.chatModelNotAllowed": "That chat model is not on the server's allowlist.",
@ -1919,6 +1920,7 @@ const cs: Record<string, string> = {
  "chat.savedToNotes": "Uloženo do poznámek sady {deck}",
  "chat.savedToNotesTrimmed": "Uloženo do poznámek sady {deck} (zkráceno, aby se vešlo)",
  "chat.savedFromChat": "Uloženo z chatu",
+  "settings.version": "Verze",
  "settings.chatNotes": "Uchovávat text poznámek pro chat",
  "settings.chatNotesNote": "Chat odpovídá z poznámek, které jsi přidal (jsou uložené u každé sady). Vypnutím bude používat jen vygenerovaný obsah.",
  "server.chatModelNotAllowed": "Tento model chatu není v povoleném seznamu serveru.",
--- a/lib/use-version.ts
+++ b/lib/use-version.ts
@ -0,0 +1,35 @@
+"use client";
+
+import { useEffect, useState } from "react";
+
+export type RunningVersion = {
+  commit: string;
+  short: string;
+  builtAt: string | null;
+  release: string | null;
+  dev: boolean;
+};
+
+/** Which release is running (from /api/healthz), for the Settings details. */
+export function useVersion(): RunningVersion | null {
+  const [version, setVersion] = useState<RunningVersion | null>(null);
+
+  useEffect(() => {
+    let cancelled = false;
+    void (async () => {
+      try {
+        const response = await fetch("/api/healthz", { cache: "no-store" });
+        if (!response.ok) return;
+        const body = (await response.json()) as RunningVersion;
+        if (!cancelled) setVersion(body);
+      } catch {
+        /* offline or old server — the row stays hidden */
+      }
+    })();
+    return () => {
+      cancelled = true;
+    };
+  }, []);
+
+  return version;
+}
--- a/next.config.ts
+++ b/next.config.ts
@ -2,12 +2,27 @@ import type { NextConfig } from "next";

 /**
 * Freezmo is meant to be opened from a phone on the same network, so the dev
- * server (which binds 0.0.0.0:3207) should accept dev-asset requests coming
- * from private hostnames. Production builds are not affected by this option.
+ * server should accept dev-asset requests coming from private hostnames.
+ * Production builds are not affected by this option.
 *
 * Add your own hostname here if Next still warns about a cross-origin request.
 */
 const nextConfig: NextConfig = {
+  /**
+   * Dev and production never share a build folder: the dev service runs with
+   * NEXT_DIST_DIR=.next-dev (see deploy/freezmo-dev.service), while a manual
+   * `npm run build` keeps producing .next for the test suites. A production
+   * build can therefore never clobber the running dev server, and the other
+   * way around.
+   */
+  distDir: process.env.NEXT_DIST_DIR || ".next",
+  /**
+   * Releases ship as self-contained standalone output: scripts/deploy.sh
+   * copies public/ and .next/static next to `.next/standalone/server.js` and
+   * runs that. `next start` keeps working too, so the existing workflows and
+   * the e2e suites are unaffected.
+   */
+  output: "standalone",
  allowedDevOrigins: [
    "127.0.0.1",
    "localhost",
--- a/public/icons/dev-favicon.svg
+++ b/public/icons/dev-favicon.svg
@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 64 64" role="img" aria-label="Freezmo Dev">
+  <rect width="64" height="64" rx="14" fill="#1c1917"/>
+  <path d="M32 9 53 21v22L32 55 11 43V21Z" fill="none" stroke="#f59e0b" stroke-width="5" stroke-linejoin="round"/>
+  <path d="M11 21l21 12 21-12M32 33v22" fill="none" stroke="#f59e0b" stroke-width="4" stroke-linejoin="round"/>
+  <path d="M22 40h6l2.4-6 3.2 10 2.2-5h6" fill="none" stroke="#fbbf24" stroke-width="2.4" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>
--- a/public/icons/dev-icon.svg
+++ b/public/icons/dev-icon.svg
@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" role="img" aria-label="Freezmo Dev">
+  <rect width="512" height="512" rx="112" fill="#1c1917"/>
+  <path d="M256 72 424 168v176L256 440 88 344V168Z" fill="none" stroke="#f59e0b" stroke-width="40" stroke-linejoin="round"/>
+  <path d="M88 168l168 96 168-96M256 264v176" fill="none" stroke="#f59e0b" stroke-width="32" stroke-linejoin="round"/>
+  <text x="256" y="316" text-anchor="middle" font-family="system-ui, sans-serif" font-size="96" font-weight="700" fill="#fbbf24">DEV</text>
+</svg>
--- a/public/sw.js
+++ b/public/sw.js
@ -9,7 +9,7 @@
 *
 * Bumping CACHE_VERSION is how a new deploy invalidates old assets.
 */
-const CACHE_VERSION = "freezmo-v33";
+const CACHE_VERSION = "freezmo-v34";
 const SHELL_CACHE = `${CACHE_VERSION}-shell`;
 const ASSET_CACHE = `${CACHE_VERSION}-assets`;

--- a/scripts/deploy.sh
+++ b/scripts/deploy.sh
@ -0,0 +1,216 @@
+#!/usr/bin/env bash
+#
+# Deploy Freezmo to production.
+#
+#   scripts/deploy.sh                 # deploy the latest origin/main
+#   scripts/deploy.sh <commit|tag>    # deploy a specific pushed commit
+#   scripts/deploy.sh --skip-tests    # skip the pre-switch e2e run (fast path)
+#
+# What it does, in order:
+#   1. refuses to run unless the working tree is clean and the target commit is
+#      already pushed to origin/main (production only runs pushed, verified code)
+#   2. exports the target commit into ~/freezmo-prod/releases/<timestamp>-<sha>
+#   3. npm ci, lint, production build (standalone output) inside that release
+#   4. (default) starts the new release on a temporary port and runs the full
+#      browser suite against it — the running production is never touched
+#   5. links shared env + data, writes release.json, flips `current` atomically,
+#      restarts the service and polls /api/healthz for the new commit
+#   6. on any failure after the switch it rolls back to the previous release
+#   7. keeps the last 5 releases
+#
+# Overridable: FREEZMO_REPO, FREEZMO_PROD, FREEZMO_SERVICE, FREEZMO_PORT,
+# FREEZMO_KEEP, FREEZMO_TEST_PORT, FREEZMO_HEALTH_TRIES (0 forces a rollback —
+# handy for testing the failure path).
+
+set -euo pipefail
+
+REPO="${FREEZMO_REPO:-$HOME/freezmo}"
+PROD="${FREEZMO_PROD:-$HOME/freezmo-prod}"
+SERVICE="${FREEZMO_SERVICE:-freezmo}"
+PORT="${FREEZMO_PORT:-3207}"
+KEEP="${FREEZMO_KEEP:-5}"
+TEST_PORT="${FREEZMO_TEST_PORT:-3299}"
+HEALTH_TRIES="${FREEZMO_HEALTH_TRIES:-45}"
+RUN_TESTS=1
+TARGET_ARG=""
+
+for arg in "$@"; do
+  case "$arg" in
+    --skip-tests) RUN_TESTS=0 ;;
+    --with-tests) RUN_TESTS=1 ;;
+    -h|--help) sed -n '2,24p' "$0"; exit 0 ;;
+    *) TARGET_ARG="$arg" ;;
+  esac
+done
+
+say() { printf '\033[1m[deploy]\033[0m %s\n' "$*"; }
+fail() { printf '\033[1;31m[deploy]\033[0m %s\n' "$*" >&2; exit 1; }
+
+# ------------------------------------------------------------------ #
+# 1. Preconditions                                                    #
+# ------------------------------------------------------------------ #
+
+[[ -d "$REPO/.git" ]] || fail "no git repository at $REPO"
+cd "$REPO"
+
+if [[ -n "$(git status --porcelain)" ]]; then
+  fail "working tree is not clean — commit or stash first (production only runs committed code)"
+fi
+
+say "fetching origin/main…"
+git fetch origin main --quiet
+
+TARGET_REF="${TARGET_ARG:-main}"
+TARGET="$(git rev-parse --verify "$TARGET_REF^{commit}")" || fail "unknown commit: $TARGET_REF"
+
+if ! git merge-base --is-ancestor "$TARGET" origin/main; then
+  fail "commit $TARGET is not on origin/main — push it first"
+fi
+
+SHORT="$(git rev-parse --short "$TARGET")"
+RELEASE="$(date +%Y%m%d-%H%M%S)-$SHORT"
+DIR="$PROD/releases/$RELEASE"
+
+say "deploying $SHORT as $RELEASE"
+mkdir -p "$PROD/releases" "$PROD/shared/freezmo/sync" "$PROD/shared/freezmo/push"
+
+# ------------------------------------------------------------------ #
+# 2. Export + build the release                                       #
+# ------------------------------------------------------------------ #
+
+mkdir -p "$DIR/src"
+git archive "$TARGET" | tar -x -C "$DIR/src"
+say "release exported to $DIR/src"
+
+cd "$DIR/src"
+say "npm ci…"
+npm ci --no-audit --no-fund >/dev/null
+
+say "lint…"
+npm run lint
+
+say "production build…"
+npm run build
+
+BUILT_AT="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
+
+# Assemble the standalone runtime: server.js + pruned node_modules, with
+# public/ and .next/static copied next to it (Next does not copy those).
+say "assembling standalone runtime…"
+mkdir -p "$DIR/server/.next"
+cp -r "$DIR/src/.next/standalone/." "$DIR/server/"
+cp -r "$DIR/src/.next/static" "$DIR/server/.next/static"
+cp -r "$DIR/src/public" "$DIR/server/public"
+
+cat > "$DIR/server/release.json" <<JSON
+{
+  "commit": "$TARGET",
+  "short": "$SHORT",
+  "builtAt": "$BUILT_AT",
+  "release": "$RELEASE"
+}
+JSON
+
+ln -sfn "$PROD/shared/env.local" "$DIR/server/.env.local"
+ln -sfn "$PROD/shared/freezmo" "$DIR/server/.freezmo"
+
+# ------------------------------------------------------------------ #
+# 3. Verify the new release on a temporary port                       #
+# ------------------------------------------------------------------ #
+
+if [[ "$RUN_TESTS" == "1" ]]; then
+  say "starting the new release on :$TEST_PORT for the e2e run…"
+  # The standalone server does not read .env files itself, so hand it the
+  # shared production env exactly like the systemd unit does.
+  set -a
+  # shellcheck disable=SC1090
+  source "$PROD/shared/env.local"
+  set +a
+  ( cd "$DIR/server" && PORT="$TEST_PORT" HOSTNAME=127.0.0.1 node server.js >"$DIR/test-server.log" 2>&1 ) &
+  TEST_PID=$!
+  cleanup_test() { kill "$TEST_PID" >/dev/null 2>&1 || true; wait "$TEST_PID" 2>/dev/null || true; }
+  trap cleanup_test EXIT
+
+  ready=0
+  for _ in $(seq 1 60); do
+    if curl -fsS --max-time 2 "http://127.0.0.1:$TEST_PORT/api/healthz" >/dev/null 2>&1; then ready=1; break; fi
+    sleep 1
+  done
+  [[ "$ready" == "1" ]] || { cat "$DIR/test-server.log" >&2; fail "the new release did not start on :$TEST_PORT"; }
+
+  say "running the browser suites against the new release…"
+  # Spawned test instances run from the release checkout (hermetic), while the
+  # suites themselves talk to the release over HTTP.
+  ( cd "$REPO" && FREEZMO_URL="http://127.0.0.1:$TEST_PORT" FREEZMO_SPAWN_CWD="$DIR/src" npm run test:e2e )
+
+  cleanup_test
+  trap - EXIT
+  say "suites passed"
+else
+  say "skipping the e2e run (--skip-tests)"
+fi
+
+# ------------------------------------------------------------------ #
+# 4. Switch, restart, health-check (roll back on failure)             #
+# ------------------------------------------------------------------ #
+
+PREVIOUS="$(readlink -f "$PROD/current" 2>/dev/null || true)"
+
+health_ok() {
+  local expected="$1" body commit
+  for ((i = 0; i < HEALTH_TRIES; i++)); do
+    body="$(curl -fsS --max-time 2 "http://127.0.0.1:$PORT/api/healthz" 2>/dev/null || true)"
+    if [[ -n "$body" ]]; then
+      commit="$(printf '%s' "$body" | grep -o '"commit":"[^"]*"' | cut -d'"' -f4 || true)"
+      # Compare short prefixes: the target may be a full sha while the release
+      # directory (and rollbacks) only carry the short one.
+      if [[ -n "$commit" && "${commit:0:7}" == "${expected:0:7}" ]]; then return 0; fi
+    fi
+    sleep 1
+  done
+  return 1
+}
+
+rollback() {
+  if [[ -n "$PREVIOUS" && -d "$PREVIOUS" ]]; then
+    say "rolling back to $(basename "$PREVIOUS")…"
+    ln -sfn "$PREVIOUS" "$PROD/current.tmp" && mv -T "$PROD/current.tmp" "$PROD/current"
+    systemctl --user restart "$SERVICE" || true
+    if health_ok "$(basename "$PREVIOUS" | sed 's/.*-//')"; then
+      say "rollback healthy — production is back on $(basename "$PREVIOUS")"
+    else
+      say "rollback restarted, but the health check is still failing — check journalctl --user -u $SERVICE"
+    fi
+  else
+    say "no previous release to roll back to"
+  fi
+  fail "deploy failed — $RELEASE is not live"
+}
+
+say "switching current -> $RELEASE…"
+ln -sfn "$DIR" "$PROD/current.tmp"
+mv -T "$PROD/current.tmp" "$PROD/current"
+
+say "restarting $SERVICE…"
+systemctl --user restart "$SERVICE"
+
+if ! health_ok "$TARGET"; then
+  rollback
+fi
+say "health check passed: $SHORT is live on :$PORT"
+
+# ------------------------------------------------------------------ #
+# 5. Prune old releases (keep the last $KEEP, never the live one)      #
+# ------------------------------------------------------------------ #
+
+LIVE="$(readlink -f "$PROD/current")"
+mapfile -t OLD < <(ls -1dt "$PROD"/releases/*/ 2>/dev/null | tail -n +$((KEEP + 1)))
+for old_dir in "${OLD[@]:-}"; do
+  [[ -n "$old_dir" ]] || continue
+  [[ "$(readlink -f "$old_dir")" == "$LIVE" ]] && continue
+  say "pruning $(basename "$old_dir")"
+  rm -rf "$old_dir"
+done
+
+say "done — $RELEASE is live (commit $SHORT, built $BUILT_AT)"
+say "production: http://127.0.0.1:$PORT  ·  logs: journalctl --user -u $SERVICE -f"
--- a/scripts/rollback.sh
+++ b/scripts/rollback.sh
@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+#
+# Roll production back to the previous release (or to a named one).
+#
+#   scripts/rollback.sh                       # previous release
+#   scripts/rollback.sh 20261011-193000-5ca0de9
+#
+# It flips the `current` symlink, restarts the service and health-checks the
+# result, so a manual rollback is the same atomic operation the deploy script
+# performs on failure.
+
+set -euo pipefail
+
+PROD="${FREEZMO_PROD:-$HOME/freezmo-prod}"
+SERVICE="${FREEZMO_SERVICE:-freezmo}"
+PORT="${FREEZMO_PORT:-3207}"
+HEALTH_TRIES="${FREEZMO_HEALTH_TRIES:-45}"
+
+say() { printf '\033[1m[rollback]\033[0m %s\n' "$*"; }
+fail() { printf '\033[1;31m[rollback]\033[0m %s\n' "$*" >&2; exit 1; }
+
+LIVE="$(readlink -f "$PROD/current" 2>/dev/null || true)"
+[[ -n "$LIVE" ]] || fail "no current release at $PROD/current"
+
+if [[ -n "${1:-}" ]]; then
+  TARGET="$(readlink -f "$PROD/releases/$1" 2>/dev/null || true)"
+  [[ -n "$TARGET" && -d "$TARGET" ]] || fail "release not found: $1"
+else
+  TARGET=""
+  for dir in "$PROD"/releases/*/; do
+    resolved="$(readlink -f "$dir")"
+    if [[ "$resolved" != "$LIVE" ]]; then
+      TARGET="$resolved"
+      break
+    fi
+  done
+  [[ -n "$TARGET" ]] || fail "no previous release to roll back to"
+fi
+
+say "current: $(basename "$LIVE")"
+say "switching to: $(basename "$TARGET")"
+ln -sfn "$TARGET" "$PROD/current.tmp"
+mv -T "$PROD/current.tmp" "$PROD/current"
+
+systemctl --user restart "$SERVICE"
+
+EXPECTED="$(grep -o '"commit":"[^"]*"' "$TARGET/server/release.json" 2>/dev/null | cut -d'"' -f4 || true)"
+[[ -n "$EXPECTED" ]] || EXPECTED="$(basename "$TARGET" | sed 's/.*-//')"
+for ((i = 0; i < HEALTH_TRIES; i++)); do
+  body="$(curl -fsS --max-time 2 "http://127.0.0.1:$PORT/api/healthz" 2>/dev/null || true)"
+  commit="$(printf '%s' "$body" | grep -o '"commit":"[^"]*"' | cut -d'"' -f4 || true)"
+  if [[ -n "$commit" && "${commit:0:7}" == "${EXPECTED:0:7}" ]]; then
+    say "healthy — production is on $(basename "$TARGET")"
+    exit 0
+  fi
+  sleep 1
+done
+
+fail "health check did not confirm $(basename "$TARGET") — check journalctl --user -u $SERVICE"
--- a/tests/lib.mjs
+++ b/tests/lib.mjs
@ -17,6 +17,12 @@ import path from "node:path";

 export const BASE = process.env.FREEZMO_URL || "http://127.0.0.1:3207";
 export const REPO = path.resolve(new URL("..", import.meta.url).pathname);
+/**
+ * Where suites that spawn their own `next start` instances run from. Defaults
+ * to the repo the tests live in; scripts/deploy.sh points it at the release
+ * checkout so the pre-switch e2e run is hermetic.
+ */
+export const SPAWN_CWD = process.env.FREEZMO_SPAWN_CWD || REPO;

 /* ------------------------------------------------------------------ */
 /* Browser                                                             */
@ -276,7 +282,7 @@ export async function waitForHttp(url, attempts = 60) {
 */
 export function spawnApp(port, env = {}) {
  const server = spawn("npx", ["next", "start", "-p", String(port), "-H", "127.0.0.1"], {
-    cwd: REPO,
+    cwd: SPAWN_CWD,
    env: { ...process.env, ...env },
    stdio: "ignore",
    detached: true,