Conflux

Conflux is a modular, actor-based real-time collaboration engine written in Rust. It provides room-based CRDT synchronization, presence/awareness broadcasting, and text chat — all over WebSockets with JWT authentication.

It’s designed as the backend core for collaborative editors, shared boards, or multiplayer apps where multiple users edit or interact in real time.

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Features

• Room-based collaboration with automatic lifecycle management
• Real-time document synchronization using Yrs (Yjs for Rust)
• Awareness broadcasting (cursor, selection, etc.)
• Chat messages and text communication between clients
• JWT authentication and per-session tracking
• Anonymous authentication mode for development and demos
• Configurable via CLI arguments and environment variables
• Dashboard API to list active rooms and their metrics
• Automatic cleanup for idle rooms
• Modular architecture split into room, room_manager, auth, and server

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Architecture Overview

    ┌────────────────────────────────────────┐
    │               Client A                 │
    │ WebSocket → send text / CRDT / cursor  │
    └────────────────────────────────────────┘
                 ▲
                 │ ws://127.0.0.1:8080/ws/:room?token=<JWT>
                 ▼
    ┌────────────────────────────────────────┐
    │               Conflux                  │
    │ Axum server + Room Manager + CRDT Core │
    │ ├── auth.rs        → JWT validation    │
    │ ├── room.rs        → per-room actor    │
    │ ├── room_manager.rs → cleanup, metrics │
    │ ├── server.rs      → WebSocket routing │
    │ └── crdt.rs        → Yrs document API  │
    └────────────────────────────────────────┘

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Project Structure

conflux-workspace/
├── conflux/             # Core backend library
│   ├── src/
│   │   ├── auth.rs
│   │   ├── crdt.rs
│   │   ├── errors.rs
│   │   ├── room.rs
│   │   ├── room_manager.rs
│   │   ├── server.rs
│   │   └── lib.rs
│   └── Cargo.toml
│
├── confluxd/            # Binary executable
│   ├── src/main.rs
│   └── Cargo.toml
│
├── frontend/            # Optional Y.js client (future)
│   └── index.html
│
└── README.md

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Endpoints

POST /login

Authenticate and receive a JWT token.

Request

{ "username": "kaylee" }

Response

{ "token": "<JWT_TOKEN>" }

Each login creates a new session with a unique session ID (sid).

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GET /dashboard

Returns all active rooms and their current state.

Response

[
  {
    "document_id": "testroom",
    "clients": 2,
    "updates": 14,
    "awareness_events": 5
  }
]

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GET /ws/:document_id?token=<JWT>

Connect to a collaborative room via WebSocket.

Example:

websocat "ws://127.0.0.1:8080/ws/testroom?token=<JWT>"

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Sending Messages (Client → Server)

You can send three kinds of messages to the server:

1. Text / Chat

{ "type": "chat", "message": "Hello everyone" }

→ Broadcasts to all clients in the same room:

{
  "Chat": {
    "document_id": "testroom",
    "from": "kaylee",
    "message": "Hello everyone"
  }
}

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2. Awareness (Presence)

{ "type": "awareness", "data": { "cursor": 42 } }

→ Notifies all connected clients about your cursor or user state.

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3. CRDT Updates

{ "type": "update", "data": "<base64_encoded_update>" }

→ The CRDT engine merges the update into the shared document using Yrs.

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4. Sync Request

{ "type": "sync_request" }

→ Requests the latest document state from the server if the client missed updates.

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Running the Server

Basic Usage

cargo run -p confluxd

CLI Options

Usage: confluxd [OPTIONS]

Options:
  -p, --port <PORT>                  Port to listen on [default: 8080]
      --host <HOST>                  Host address to bind to [default: 127.0.0.1]
      --anonymous                    Enable anonymous authentication (no signature verification)
      --idle-timeout <IDLE_TIMEOUT>  Room idle timeout in seconds [default: 60]
  -h, --help                         Print help

Examples

# Default (localhost:8080)
cargo run -p confluxd

# Custom port and host
cargo run -p confluxd -- --port 3000 --host 0.0.0.0

# Anonymous mode (clients can generate their own JWTs)
cargo run -p confluxd -- --anonymous

# Production with custom settings
CONFLUX_JWT_SECRET=your-secret-here cargo run -p confluxd --release -- --port 8080 --host 0.0.0.0

Output:

INFO confluxd: Conflux server running at ws://127.0.0.1:8080

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Example Session

1. Start the server

bash cargo run -p confluxd

1. Get a JWT

bash curl -X POST http://127.0.0.1:8080/login \ -H "Content-Type: application/json" \ -d '{"username":"kaylee"}'

1. Connect with the token

bash websocat "ws://127.0.0.1:8080/ws/testroom?token=<JWT>"

1. Send messages from the client:

{"type": "chat", "message": "hi from client 1"} {"type": "awareness", "data": {"cursor": 101}} {"type": "sync_request"}

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Configuration

Environment Variables

Variable	Required	Description
CONFLUX_JWT_SECRET	Yes (production)	Secret key for signing/verifying JWTs. Required in release builds.

In debug builds, a default development secret is used if CONFLUX_JWT_SECRET is not set (with a warning).

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Security

• JWT tokens expire after 24 hours
• Each login generates a unique session ID (sid)
• Tokens can be revoked by rotating the CONFLUX_JWT_SECRET
• Release builds panic on startup if CONFLUX_JWT_SECRET is not set
• Anonymous mode (--anonymous) skips signature verification - use only for development/demos
• All state is ephemeral (no DB dependency)

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License

MIT License Copyright (c) 2025 Kaylee

Demo