Muxy Extensions Developer Kit

Building Twitch Extensions is hard. Muxy makes it easier.

As one of the first developers to make an Extension, we spent months developing a powerful enough backend to power all of the apps we wanted to bring to Twitch. We're providing our backend and libraries so you don't need extensive domain knowledge to build an Overlay App or Twitch Extension.

Get started

Muxy Overlay App Twitch Extension


The missing piece of Twitch Extension Development. Run at Twitch scale without worring about servers. We handle the entire backend so you can focus on creating interactive experiences for Twitch viewers.


Take advantage of our libraries! Interact with Twitch, use our specialized data processing algorithms, and utilize our JSON store to connect your server. Broadcast data changes to everyone using your app in real time!

Dev environment

The Muxy Twitch Extensions dev environment mimics the live Twitch environment. It handles user authentication, analytics, context switching, and environment detection. We even provide live code updating so you don't have to refresh!

Third Party Apps

Already have an existing game or application? Let broadcasters sync data with their Twitch account with a secure PIN, and simple POST request.

Check out the projects!

Muxy Extensions JavaScript Library

The Muxy Extensions JS library provides easy access to Muxy's powerful backend architecture. The Muxy Extension library provides four main sections of functionality: Data Storage, an Event Manager, a Twitch Client and a Google Analytics system.

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Muxy Overlay App Rig

This repo provides everything you need to get started building a full interactive app integrated into Muxy's Overlay experience on Twitch.

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Muxy Extension Rig

The Rig simulates the Twitch environment that Twitch Extensions run in. Combined with the Muxy SDK it allows Twitch Extensions to safely be sandboxed away from production data and any hiccups that can happen on Twitch's site. When running in the rig the Muxy SDK also provides a pubsub system that works exactly like the production one on Twitch.

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