Raw Twitch in. Typed Twitch out.

velho is one dependency for four Twitch surfaces — OAuth, Helix, chat, and EventSub. It parses each wire format into typed values and validates them with Zod at the boundary.

bun add velhoRead the docs GitHub

Then run bunx velho-setup to walk the OAuth flow and write the credentials into your .env file.

import { TwitchChatClient } from "velho";

const chat = new TwitchChatClient({
  username: "velhobot",
  token: `oauth:${accessToken}`,
  autoJoin: ["#velho"],
  reconnect: true,
});

// Twitch sends this:
// @badges=subscriber/12;color=#1E90FF;display-name=kettu
// :kettu!kettu@kettu.tmi.twitch.tv PRIVMSG #velho :!ping

chat.on("message", (message) => {
  message.channel; // "#velho"
  message.username; // "kettu"
  message.text; // "!ping"
});

await chat.connect();

Modules

Auth

App access, authorization code, and refresh flows. Tokens are cached and renewed before they expire.

TwitchAuth

Helix

Typed GET and POST against any Helix path. Pass a Zod schema to shape the response and read rate limits off every call.

HelixClient

Chat

Join channels, listen, and say things back. PING is answered and dropped sockets reconnect on their own.

TwitchChatClient

EventSub

Verify webhook signatures in constant time and answer the challenge, or hold a WebSocket session open.

handleEventSubWebhook, EventSubWebSocketClient

velho is Finnish for wizard. MIT licensed, built by Joni Juntto. See also Visp, stream tooling for Twitch creators.