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	10,599	26,054
Forks	814	10,416
Open Issues	147	2,051
Last Commit	Oct 16, 2026	Oct 16, 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

Zulip26,054

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