Retichat Web

⚠️ Work in Progress — This project is under active development. APIs, protocols, and UI may change.
🤖 AI-Assisted Development — A significant portion of this codebase was generated and refined with AI coding assistance (GitHub Copilot / Claude). All generated code has been reviewed and tested by a human developer.

Browser chat client for the Reticulum Network Stack. Drop this folder onto any static web server — no npm, no build step, no Node.js required.

Connects to a Reticulum-post HTTP exchange node to send and receive encrypted LXMF messages across the Reticulum mesh.

┌──────────────────────────────────────────────┐
│  Retichat Web (Browser)                      │
│  ┌──────────┐  ┌──────────┐  ┌────────────┐ │
│  │  UI (JS) │──│  RNS.js  │──│  HTTP Poll  │ │
│  │  Two-panel│  │  LXMF    │  │  Exchange   │ │
│  │  layout  │  │  Crypto  │  │  Client     │ │
│  └──────────┘  └──────────┘  └──────┬─────┘ │
└─────────────────────────────────────┼───────┘
                                      │ HTTP POST
                                      ▼
┌──────────────────────────────────────────────┐
│  Reticulum-post (PHP Router)                 │
│  ┌──────────────────┐  ┌──────────────────┐ │
│  │  HTTP Exchange   │  │  Python Bridge   │ │
│  │  API (index.php) │──│  (PostInterface) │ │
│  └──────────────────┘  └────────┬─────────┘ │
└─────────────────────────────────┼───────────┘
                                  │
                          ┌───────┴───────┐
                          │  Reticulum    │
                          │  Backbone     │
                          └───────────────┘

The primary transport mode. The browser client pulls by periodically HTTP POSTing queued outbound packets to the PHP router, and receiving any inbound packets queued for it in the response. This works through firewalls, shared hosting, and NAT — the client initiates every request, the server never pushes.

Client                              PHP Router
  │                                     │
  │── POST /exchange (outbound pkts) ──►│
  │◄─ JSON response (inbound pkts) ────│
  │                                     │
  │        ... wait (poll interval) ... │
  │                                     │
  │── POST /exchange (outbound pkts) ──►│
  │◄─ JSON response (inbound pkts) ────│

• No WebSocket, no raw sockets, no open inbound ports
• Works behind any static web host or CDN
• Poll interval is adaptive (speeds up when messages are flowing)

When two nodes both have registered interfaces and have exchanged announces, the transport can operate in push-push mode. Either side can initiate a transfer at any time — packets flow bidirectionally without polling. This requires both nodes to be reachable (e.g., via Direct Sockets or a mutually accessible exchange node).

Node A                               Node B
  │                                     │
  │──── announce (lxmf.delivery) ──────►│  path established
  │◄─── announce (lxmf.delivery) ──────│  bidirectional
  │                                     │
  │──── LXMF message ──────────────────►│  either side pushes
  │◄─── LXMF message ──────────────────│  independently

• Zero tooling — pure ES modules loaded directly by the browser via import maps
• Two-panel responsive UI — sidebar + chat on wide screens (≥800px), slide-in chat on phones, modeled after Retichat iOS
• Dark theme by default with light mode toggle (matches iOS design language)
• HTTP exchange transport — no WebSocket, no raw sockets, works behind any hosting
• End-to-end encryption — AES-256-CBC + X25519 key exchange matching Python RNS reference
• Privacy filter — only accept messages from contacts you've explicitly added
• Contact management — add by destination hash or lxmf:///lxma:// link, share your own identity
• Glass-morphism UI — translucent surfaces matching iOS GlassBackground design language

1. Edit config.json — set exchangeUrl to your Reticulum-post node
2. Drop this folder on any static web server
3. Open in a browser

{
    "exchangeUrl": "https://your-node.example.com/reticulum",
    "displayName": "Retichat Web",
    "announceIntervalMs": 300000
}

├── index.html              Entry point (import map + mount)
├── app.js                  Main application (UI + RNS client)
├── config.json             Node URL + preferences
├── style.css               Theme system + responsive layout
├── retichat-icon.png       App icon (favicon + PWA)
└── lib/
    ├── rns/                RNS protocol library (ES modules)
    │   └── reticulum.js    Identity, Destination, LXMF, interfaces
    └── shims/              Browser polyfills
        ├── crypto.js       Web Crypto API shim
        ├── net.js          Network stubs
        └── ws.js           WebSocket stubs

All external dependencies are loaded from CDN via import map in index.html:

• @noble/curves — elliptic curve cryptography
• @noble/hashes — SHA-256, SHA-512
• msgpackr — MessagePack encoding
• buffer — Node.js Buffer polyfill

No package.json. No node_modules. No build step.

• Reticulum-post — PHP HTTP exchange router + Python bridge
• Reticulum — Python reference implementation
• Retichat Android — Native Android client
• Retichat iOS — Native iOS client

MIT