Discourse vs Mattermost
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
 Discourse | Mattermost | |
|---|---|---|
| License | GPL-2.0 | — |
| Self-hostable | Yes | No |
| GitHub Stars | 46,646 | 35,990 |
| Forks | 8,857 | 8,460 |
| Open Issues | 170 | 836 |
| Last Commit | Mar 28, 2026 | Mar 28, 2026 |
| First Released | Jan 12, 2013 | Jun 15, 2015 |
| Categories | ||
| Tags | — |
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