A tiny WebRTC experiment for sending letters instead of instant messages. A sent letter travels across a Leaflet map for a computed duration; both peers see the same marker progress, and the body stays sealed in the UI until arrival.
Letters no longer appear by default on first load. After a letter is delivered, click its card in the Inbox to open and read it.
Install dependencies once:
cd server && npm install
cd ../client && npm installStart the local signaling relay:
cd server
npm run devStart the client:
cd client
npm run devOpen the client in two browser windows. Click Host in one window, copy the same room code into the other, then click Join. Wait until both show p2p connected before sending a letter.
This repo includes vercel.json so Vercel can build and host the Vite client from the repo root:
- Build command:
npm run build - Output directory:
client/dist
On Vercel, the client uses the public PeerJS broker for room signaling. That avoids the serverless limitation where each WebSocket isolate keeps its own in-memory room map, so Host and Join never meet.
Local development still uses the standalone relay at ws://localhost:8787. You can force a custom relay anywhere with VITE_SIGNALING_URL in client/.env.
The optional /api/ws function remains available if you point VITE_SIGNALING_URL at it, but it only works reliably when both peers land on the same Fluid compute instance (or when you run server/ as a long-lived process).
Letter payloads travel through the peer data channel after the connection is established. The delayed-reading behavior in this prototype is enforced by the UI rather than hard cryptography.