Fluxer vs Mattermost
Comparing two open source alternatives to Discord and Slack. Use the comparison below to decide which one fits your needs.
Fluxer
AGPL-3.0A free and open source instant messaging and VoIP chat app for friends, groups, and communities.
Mattermost
Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..
Side-by-side comparison
| Fluxer | Mattermost | |
|---|---|---|
| License | AGPL-3.0 | — |
| Self-hostable | Yes | No |
| GitHub Stars | 10,468 | 39,226 |
| Forks | 779 | 9,030 |
| Open Issues | 153 | 1,038 |
| Last Commit | Oct 1, 2026 | Sep 30, 2026 |
| First Released | Jan 1, 2026 | Jun 15, 2015 |
| Categories | ||
| Tags | — |
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