Chatto vs Mattermost
Comparing two open source alternatives to Slack and Discord . Use the comparison below to decide which one fits your needs.
Chatto
AGPL-3.0A self-hosted chat application for teams and communities with video calls, voice calls, and screen sharing.
Mattermost
Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..
Side-by-side comparison
| Chatto | Mattermost | |
|---|---|---|
| License | AGPL-3.0 | — |
| Self-hostable | Yes | No |
| GitHub Stars | 1,264 | 38,354 |
| Forks | 46 | 8,817 |
| Open Issues | 158 | 924 |
| Last Commit | Jul 9, 2026 | Jul 8, 2026 |
| First Released | Apr 8, 2026 | Jun 15, 2015 |
| Categories | ||
| Tags | — |
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