Open-source team chat apps in 2026

7 open-source projects, ranked by GitHub stars and how recently each was worked on. Zulip leads with 26k stars, ahead of Element-web. 6 had code pushed in the last three months. Most common licenses: AGPL-3.0 (3), Apache-2.0 (2) and GPL-3.0 (2). Commercial team chat apps are listed separately.

All open-source team chat apps, ranked

Complete systems you can adopt 7

1
Zulip zulip
Zulip server and web application. Open-source team chat that helps teams stay productive and focused.

Complete system Production-ready Your team finds Slack threads chaotic and wants organised, asynchronous conversations, self-hosted or hosted.
★ 26k Apache-2.0 Python Active, pushed today
2
Element-web element-hq
A glossy Matrix collaboration client for the web.

Complete system Production-ready You use Matrix and want the most complete client, or want to host your own web client.
★ 14k AGPL-3.0 TypeScript Active, pushed today
3
Chat tinode
Instant messaging platform. Backend in Go. Clients: Swift iOS, Java Android, JS webapp, scriptable command line; chatbots

Complete system Usable You want to embed or run your own messaging service with ready clients.
★ 14k GPL-3.0 Go Active, pushed 8 days ago
4
Synapse element-hq
Synapse: Matrix homeserver written in Python/Twisted + Rust

Complete system Production-ready You want to run your own Matrix server for a team or community that can federate with others.
★ 4.8k AGPL-3.0 Python Active, pushed today
5
Quiet TryQuiet
A private, p2p alternative to Slack and Discord built on Tor & IPFS

Complete system Experimental A small group values running chat with no server at all and accepts missing features compared with Slack.
★ 2.7k GPL-3.0 TypeScript Active, pushed today
6
Colanode colanode
Open-source and local-first Slack and Notion alternative that puts you in control of your data

Complete system Experimental A small team wants chat and docs together on its own server with offline support.
★ 5.2k Apache-2.0 TypeScript Slowing, pushed 7 months ago
7
Raven frappe
Simple, open source team messaging platform

Complete system Usable Your company runs ERPNext or other Frappe apps and wants chat inside the same system.
★ 839 AGPL-3.0 TypeScript Active, pushed today

Compared head to head

Discord vs Microsoft Teams Discord vs Slack Discord vs Zulip Discord vs Element-web Chat vs Discord Microsoft Teams vs Slack Microsoft Teams vs Zulip Element-web vs Microsoft Teams Chat vs Microsoft Teams Slack vs Zulip Element-web vs Slack Chat vs Slack Element-web vs Zulip Chat vs Zulip Chat vs Element-web

Looking for an alternative to

Slack Microsoft Teams Discord

Open-source licenses

Network copyleft: 3. Like GPL, and running a changed version as a web service counts as distributing it, so its users get the source too.
Permissive: 2. Use it anywhere, including in closed products. You keep the copyright notice; Apache-2.0 also grants patent rights.
Strong copyleft: 2. If you distribute the program or anything built on it, you must release the whole source under the same license.

Languages

TypeScript 4, Python 2 and Go 1.

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