Fluxer vs Zulip

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

Fluxer

AGPL-3.0

A free and open source instant messaging and VoIP chat app for friends, groups, and communities.

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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

	Fluxer	Zulip
License	AGPL-3.0	Apache-2.0
Self-hostable	Yes	Yes
GitHub Stars	10,537	26,027
Forks	797	10,378
Open Issues	151	2,048
Last Commit	Oct 10, 2026	Oct 9, 2026
First Released	Jan 1, 2026	Sep 25, 2015
Categories	Team Chat & Messaging Tools	Team Chat & Messaging Tools
Tags	#chat #messaging #voice chat #community #self hosted	#chat #messaging #collaboration

GitHub stars over time

Fluxer

Zulip26,027

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