Mattermost vs Raven
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..
Side-by-side comparison
| Mattermost |  Raven | |
|---|---|---|
| License | — | AGPL-3.0 |
| Self-hostable | No | No |
| GitHub Stars | 35,990 | 671 |
| Forks | 8,460 | 298 |
| Open Issues | 836 | 162 |
| Last Commit | Mar 28, 2026 | Mar 27, 2026 |
| First Released | Jun 15, 2015 | Feb 10, 2023 |
| Categories | ||
| Tags | — |
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