Jannis Braun
b6842c5590
Transferring ownership or kicking a member surfaced "Target user is not a
member of this DM channel" whenever the target was a federated user.
Root cause: the client passed `canonical.id` from `useCanonicalUserView`,
which returns the user's HOME id when the home view is in the userViews
cache. After owner-routing the request to the owner instance, that
instance's `dm_members.userId` (its own local replicated id) never
matched the home id, so `isDmMember` returned false. The same failure
mode applied across any cross-instance scenario where the
channel-serving instance and the owner-serving instance disagree on the
local replicated user id for the same federated user.
Fix: both endpoints now accept federated identification, mirroring the
existing pattern on `POST /api/dm/:id/members`:
- `POST /api/dm/:id/transfer` body: `{ newOwnerId? } | { homeUserId, homeInstance }`.
Federated args win when both are supplied (strictly more specific).
- `DELETE /api/dm/:id/members/:targetUserId` reads optional
`?homeInstance=<origin>` query; when present, the URL segment is
treated as a homeUserId and resolved via `resolveOrCreateReplicatedUser`.
Client `api.dm.kickMember` and `api.dm.transferOwnership` gain an
optional `federated` argument; `DmRosterPanel` and `MobileGroupDmInfo`
pass it whenever the target has `homeUserId` + `homeInstance` populated.
Adds 5 server tests (3 transfer + 2 kick) covering federated targets,
the federated-wins-over-local precedence rule, and federated-non-member
rejection. Updates 2 client routing tests and 2 DmRosterPanel test
assertions for the new signature. Updates `docs/systems/dm-system.md`
and `docs/systems/api.md`.
Server: 965 tests pass (was 960). Web: 362 tests pass (was 360).
Backspace
Open-source, self-hosted Discord alternative built with TypeScript.
Features
- Real-time text messaging with WebSocket
- Servers, channels, and role-based permission management
- Voice and video chat via LiveKit
- Screen sharing with configurable quality (VP9)
- Direct messages (1-on-1 and group DMs up to 10)
- DM voice/video calls with ringing
- Friend system with requests
- File uploads and image sharing
- Markdown message formatting with syntax highlighting
- Message reactions, replies, and editing
- Typing indicators, presence status, and read states
- Invite system with shareable codes
- Instance-level admin panel (streaming limits)
- Desktop app (Electron)
- Mobile-responsive web UI
- Docker deployment
Tech Stack
| Layer | Technology |
|---|---|
| Backend | Fastify + TypeScript |
| Database | SQLite (better-sqlite3) + Drizzle ORM |
| Auth | JWT + bcrypt |
| Real-time | WebSocket (ws) |
| Frontend | React 18 + Tailwind CSS + Zustand |
| Voice/Video | LiveKit |
| Desktop | Electron |
| Build | Vite + pnpm workspaces |
Quick Start with Docker
# Clone the repository
git clone https://github.com/your-username/backspace.git
cd backspace
# Create environment file
cp .env.example .env
# Generate a JWT secret
echo "JWT_SECRET=$(openssl rand -hex 32)" >> .env
# Start Backspace
docker compose up -d
Open http://localhost:3000 in your browser. A default server "Backspace" is created automatically.
Default admin account: admin / admin123 (change this after first login).
Development Setup
Prerequisites
- Node.js 20+
- pnpm 8+
Install
pnpm install
Configure
cp .env.example .env
# Edit .env with your settings (generate a JWT_SECRET)
Run
# Start both server and web dev server
pnpm dev
# Or start individually
pnpm dev:server # API server on :3005
pnpm dev:web # Vite dev server on :5173
Build
pnpm build
This builds the shared types, server, and web frontend. The server serves the built frontend in production mode.
Project Structure
Backspace/
├── packages/
│ ├── shared/ # Shared TypeScript types & permissions
│ ├── server/ # Fastify API + WebSocket server
│ ├── web/ # React frontend (Vite + Tailwind)
│ └── desktop/ # Electron desktop app
├── data/ # SQLite DB + uploads (created at runtime)
├── Dockerfile
├── docker-compose.yml
└── .env.example
Voice & Video
Voice and video requires a LiveKit server. Set these in your .env:
LIVEKIT_URL=wss://your-livekit-server
LIVEKIT_API_KEY=your-api-key
LIVEKIT_API_SECRET=your-api-secret
Without LiveKit configured, text chat works fully but voice/video channels will not connect.
API
The server exposes a REST API and WebSocket endpoint:
- REST API:
http://localhost:3000/api/* - WebSocket:
ws://localhost:3000/ws - Health check:
GET /api/health
See CLAUDE.md for the full API reference.
Desktop App
The Electron desktop app wraps the web UI and adds system tray, notifications, and native window controls.
cd packages/desktop
pnpm build:ts # Compile TypeScript
pnpm dev # Run in development
pnpm build # Package for distribution
License
MIT