quicrtc

TypeScript client for quicrtc, wire-compatible with the Go server.

Install

npm install quicrtc

Requires WebTransport in the browser or Node 18+ with a WebTransport-capable runtime.

Quick start

import { QuicRTCClient, TrackKind } from 'quicrtc';

const client = new QuicRTCClient();
await client.connect('https://your-server/wt', {
  slug: 'auth-token',
  certHash: 'base64url-sha256-der-hash', // only for self-signed dev certs
});

// Receive on a named track
const au = await client.recvOn('reasoning');
console.log(new TextDecoder().decode(au.bytes));

// Publish a track back to the server
const sender = await client.publish({ name: 'actions', kind: TrackKind.ToolCalls });
await sender.send({
  bytes: new TextEncoder().encode('{"type":"click","x":100,"y":200}'),
  keyframe: true,
  ptsMicro: 0,
  seq: 0,
});

await client.close();

A framework-free browser viewer that exercises every track kind lives in examples/viewer/.

API

QuicRTCClient

const client = new QuicRTCClient();
await client.connect(url, options);

interface ClientOptions {
  slug: string;                  // auth credential (shared secret or JWT)
  certHash?: string;             // SHA-256 cert pin for self-signed dev certs
  insecureSkipVerify?: boolean;  // dev only
  helloTimeout?: number;         // ms
  sessionId?: string;            // resume an earlier session
  features?: string[];           // capabilities to negotiate
}

Methods:

• recv(), recvOn(trackName) — pull next AU from primary or named track
• publish(track) — bidirectional: publish a track back to the server
• requestKeyframe(trackName) — subscriber-driven keyframe request
• sendDatagram(payload), receiveDatagram() — raw QUIC datagrams
• getDataChannel() — reliable bidi messaging
• getSDP(), getRemoteTracks(), getStats() — introspection
• close()

Tracks

enum TrackKind {
  Video = 'video',
  Audio = 'audio',
  Tokens = 'tokens',
  ToolCalls = 'tool_calls',
  Telemetry = 'telemetry',
}

// Pull
const au = await track.recv();

// Push
track.onAU((au) => { /* ... */ });

Data channel

const dc = client.getDataChannel();
await dc.sendText('hello');
await dc.send(new Uint8Array([1, 2, 3]));
dc.onMessage((data) => { /* ... */ });

Wire codec performance

Allocation-free on the hot path. Reproduce with npm run bench:

• Control frame encode — ~0.1 µs
• Feed frame encode (1 KB payload) — ~0.3 µs
• Datagram envelope encode (64 B) — ~0.1 µs
• Datagram envelope decode — <0.1 µs
• Backpressure marshal (with needs_keyframe) — ~0.2 µs
• HELLO / SDP JSON marshal + unmarshal — ~0.4 µs each

End-to-end numbers (Go server side) live in the repo's benchmarks suite.

Browser support

Note: WebTransport is an evolving web standard. Browser support and implementation details may change.

| Browser | WebTransport | Status | |-------------|--------------|-------------------------| | Chrome 114+ | Native | Full | | Edge 114+ | Native | Full | | Safari 26.4+ (iOS / macOS) | Native | Full (shipped March 2026) | | Firefox | Behind flag | Enable network.webtransport.enabled |

License

Apache 2.0 — see LICENSE.