Mattermost vs Zulip
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..
Zulip
Apache-2.0Open-source team chat with a unique topic-based threading model that makes it easy to follow multiple conversations.
Side-by-side comparison
| Mattermost | Zulip | |
|---|---|---|
| License | — | Apache-2.0 |
| Self-hostable | No | Yes |
| GitHub Stars | 36,669 | 25,165 |
| Forks | 8,608 | 9,823 |
| Open Issues | 851 | 2,059 |
| Last Commit | May 12, 2026 | May 12, 2026 |
| First Released | Jun 15, 2015 | Sep 25, 2015 |
| Categories | ||
| Tags | — |
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