# Tech Stack — BizGaze Connect

> Living document. **Last updated: 2026-10-27.** Update this file whenever a dependency, platform, service, or
> tool is added/removed/version-bumped. See [Maintaining this file](#maintaining-this-file) and the
> [Changelog](#changelog) at the bottom.

## What this project is

BizGaze Connect is a self-hosted team **chat + meetings + calling** product (evolved from a remote
screen-sharing/"remote-access" tool, whose agent console still lives in the repo). One backend serves a web app
and is wrapped by native mobile (Capacitor) and desktop (Electron) shells. The UI loads live from the server, so
web changes deploy **without** rebuilding the native apps.

**Architecture style:** thin, dependency-light Node backend (custom modules, no web framework) + a single-page
vanilla-JS web UI + native shells that wrap the web and add native capabilities (push, calling, screen capture,
file access). Real-time via WebSockets; meeting media via WebRTC (P2P mesh, or LiveKit SFU when enabled).

---

## Backend (server)

- **Runtime:** Node.js — `engines` requires **>= 22.5**; the Docker image is **`node:24-alpine`**.
- **HTTP/HTTPS:** Node built-in `http`/`https` modules. **No Express/Koa/Fastify** — a small custom router
  (`routes.js`) maps `"METHOD /path"` to handlers; static files + authenticated downloads via `static.js`.
- **WebSockets:** [`ws`](https://github.com/websockets/ws) `^8.18` (`WebSocketServer` on `/ws`) — chat, presence,
  meeting signaling (SDP/ICE relay + consent).
- **Structure (server/):** `server.js` (wiring), `routes.js` (HTTP JSON API), `repos.js` (all SQL / data access),
  `signaling.js` (WS), `calls.js`, `chat.js`, `presence.js`, `session.js`/`auth.js`, `push.js`, `livekit.js`,
  `media.js`, `mailer.js`, `webhooks.js`, `bizgaze.js` (BizGaze identity provider), `directory.js`, `config.js`.
- **Media tooling:** **ffmpeg** (in the image) for server-side video poster thumbnails.

## Data layer

- **Database:** **PostgreSQL 16** (`pg` `^8.13`). This is the only backend — **SQLite was retired 2026-08-12**;
  one schema source of truth at `server/db/schema.pg.sql`. Selected via `DB_BACKEND=pg` / `DATABASE_URL`.
- **DB access:** hand-written SQL through an async adapter (`server/dbx.js`, `server/db/`), centralized in
  `repos.js`. No ORM.
- **Cache / pub-sub:** **Redis 7** (`redis` `^4.7`) for cross-instance real-time fan-out (chat/presence) —
  **optional**, only when `PUBSUB_BACKEND=redis`; default is in-memory single-instance (`pubsub.js`).

## Real-time & media

- **WebRTC** for calls/meetings: built-in **P2P mesh** by default; **LiveKit SFU** when configured.
- **LiveKit SFU server:** `livekit/livekit-server:**v1.9**` (Docker, `sfu` compose profile, dormant unless
  `LIVEKIT_*` env is set). Server mints per-user JWT join tokens (`server/livekit.js`).
- **LiveKit clients:**
  - Web: self-hosted **`livekit-client` ~2.20** UMD (`server/public/vendor/livekit-client.umd.min.js`).
  - iOS: **LiveKit Swift SDK `2.15.3`** (SPM, `client-sdk-swift`, product `LiveKit`).
  - Android: **LiveKit Android SDK** (`io.livekit:livekit-android`) — planned for native-calling Increment 2.

## Web client (`server/public/`)

- **Vanilla JavaScript SPA** — `home.html` is the app (large single file with inline JS). **No framework, no
  bundler, no build step.** Supporting files: `icons.js` (shared Lucide icon set via `ic()`), `connect.html`
  (embed), `sw.js` (service worker), `bizconnect-toast.js`.
- **PWA:** installable; service worker for Web Push + offline shell.
- **Icons:** Lucide (shared set, rendered through `ic()`); no emoji as control icons.

## Mobile app (`mobile/`) — Capacitor

- **Framework:** **Capacitor 8** (`@capacitor/core` `^8`) — a native shell (iOS WKWebView / Android WebView)
  loading the remote web UI from `https://remote.bizgaze.com`. **Not Flutter/React Native.**
- **Official plugins (`^8`):** App, Camera, Filesystem, Keyboard, Share, Push Notifications, Splash Screen,
  Status Bar; **community** `@capacitor-community/safe-area` `^8`; `@capacitor/assets` `^3` (icons/splash).
- **Local/custom plugins (`mobile/plugins/`):**
  - `native-call` — native calling. **iOS:** Swift, CallKit + PushKit (VoIP) + LiveKit Swift SDK (native media,
    video tiles, screen-share via a ReplayKit broadcast extension), on-device live transcription
    (`SFSpeechRecognizer`). **Android:** Java, full-screen incoming-call UI over the lock screen + a
    `FirebaseMessagingService` woken by high-priority FCM data messages (native LiveKit media = Increment 2, WIP).
  - `audio-route` (iOS audio output routing), `media-library` (save to Photos/gallery), `share-inbox` (inbound
    share sheet), `file-opener` (native Quick Look / open-with).
- **iOS build:** Capacitor 8 + **SPM** (CocoaPods retired); Xcode 26; a share extension + a broadcast extension.
- **Android build:** JDK **21**, AGP 8.7 / Gradle 8.11, target SDK 36, edge-to-edge; manifest patched in CI
  (`mobile/scripts/android-patch.js`) since `mobile/android/` is generated fresh per build.

## Desktop app (`desktop/`) — Electron

- **Electron 31** + **electron-builder 24** (NSIS/Windows, DMG/mac, AppImage/Linux) + **electron-updater 6**
  (auto-update from `https://remote.bizgaze.com/downloads/`). Wraps the web UI and adds native screen capture.
  Optional **`@nut-tree-fork/nut-js`** for input automation.

## Native host agent (`agent/`) — Electron

- Legacy **remote-access agent** (`remote-access-agent`): Electron 31 host for screen capture, WebRTC,
  consent, and OS input injection (`@nut-tree-fork/nut-js`), signaling over `ws`.

## Push notifications

- **Web Push** via VAPID (`web-push` `^3.6`) for browsers/PWA.
- **Android:** Firebase Cloud Messaging (FCM) — Firebase project `bizgaze-connect`; client `google-services.json`
  ships in the APK; server uses a service-account key (base64 in `.env`). High-priority **data** messages wake the
  native-call plugin for incoming calls.
- **iOS:** Apple Push Notification service (APNs) over HTTP/2 with a token (`.p8`) auth key, including **VoIP
  pushes** (PushKit → CallKit) for incoming calls.

## Infrastructure & deployment

- **Containers:** Docker + Docker Compose (`Dockerfile`, `docker-compose.yml`). Services: `app` (Node),
  `bizgazepg` (Postgres 16), `bizgazeredis` (Redis 7, `scale` profile), `livekit` (SFU, `sfu` profile).
- **Reverse proxy / TLS:** **Nginx Proxy Manager** (external, shared `nginx_proxy_manager_default` network) —
  terminates HTTPS and proxies `remote.bizgaze.com` → `app:8090` and `wss://livekit.bizgaze.com` → LiveKit.
- **Persistence:** named Docker volumes — app data (`/data`: uploads, recordings, transcripts, downloads) and
  Postgres data.
- **Deploy flow:** push to `master` (Gitea remote `code.bizgaze.com`) → `redeploy.sh` (plink/SSH to the host) →
  server-side `deploy.sh` (git pull + docker rebuild + recreate). Secrets live in a gitignored `.env` on the
  server (`/opt/bizgaze-support/.env`); see `.env.example`.
- **CI (mobile builds):** **Codemagic** (`codemagic.yaml`) — iOS (`mac_mini_m2`, SPM, publishes to TestFlight) and
  Android (`mac_mini_m2`, Node 22, JDK 21, produces an installable debug APK).

## External integrations

- **BizGaze** SSO / identity provider + outbound webhook (`bizgaze.js`, `webhooks.js`).
- **SMTP email** via **Nodemailer** `^6.9` (optional) — meeting invites to external participants.
- **GIPHY** GIF search (server-proxied, optional, key-gated).
- **TURN/STUN** for WebRTC NAT traversal (credentials via `.env`).

## Dev & test tooling

- **Local DB for tests:** PostgreSQL 16 (local).
- **Browser automation:** `puppeteer-core` driving local Chrome (scratch testing).
- **Android debugging:** `adb` (`platform-tools`).
- **Shell/OS:** developed on Windows; Git Bash + PowerShell; deploy via plink (PuTTY).

---

## Repo layout (key directories)

| Path | What |
|---|---|
| `server/` | Node backend (API, WS, data access, push, media) |
| `server/public/` | Vanilla-JS web UI (`home.html`, `icons.js`, `sw.js`, `vendor/`) |
| `server/db/` | PostgreSQL schema + DB adapter |
| `mobile/` | Capacitor app (iOS/Android) |
| `mobile/plugins/` | Custom Capacitor plugins (native-call, audio-route, media-library, share-inbox, file-opener) |
| `desktop/` | Electron technician desktop client |
| `agent/` | Legacy Electron remote-access host agent |
| `Dockerfile`, `docker-compose.yml`, `livekit.yaml` | Deploy stack |
| `codemagic.yaml` | Mobile CI (iOS + Android) |
| `redeploy.sh`, `deploy.sh` | Deployment |
| `ARCHITECTURE.md`, `DEPLOY.md`, `CLIENTS.md`, `README.md` | Docs |

---

## Maintaining this file

Update this document in the **same commit** as any change that alters the stack, specifically when you:

- add/remove a dependency, or bump a major version (server `package.json`, `mobile/package.json`,
  `desktop/package.json`, `agent/package.json`, plugin manifests);
- change a platform/toolchain version (Node, Postgres, Redis, LiveKit, Capacitor, Electron, JDK, Xcode);
- add/remove a service in `docker-compose.yml` or a build workflow in `codemagic.yaml`;
- add a new custom Capacitor plugin or a new external integration.

Bump the **Last updated** date at the top and add a line to the Changelog below.

## Changelog

- **2026-10-27** — Initial tech-stack document created.