Mattermost vs Zulip

Comparing two open source alternatives to Discord and Slack. Use the comparison below to decide which one fits your needs.

Mattermost

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

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Zulip

Apache-2.0

Open-source team chat with a unique topic-based threading model that makes it easy to follow multiple conversations.

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Side-by-side comparison

	Mattermost	Zulip
License	—	Apache-2.0
Self-hostable	No	Yes
GitHub Stars	39,280	25,999
Forks	9,036	10,356
Open Issues	1,049	2,044
Last Commit	Oct 6, 2026	Oct 6, 2026
First Released	Jun 15, 2015	Sep 25, 2015
Categories	Team Chat & Messaging Tools	Team Chat & Messaging Tools
Tags	—	#chat #messaging #collaboration

GitHub stars over time

Mattermost39,280

Zulip

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