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	39,166	25,944
Forks	9,018	10,285
Open Issues	1,014	2,027
Last Commit	Sep 24, 2026	Sep 23, 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

Mattermost39,166

Zulip

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