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 | 47,629 | 38,716 |
| Forks | 8,982 | 8,892 |
| Open Issues | 236 | 987 |
| Last Commit | Aug 10, 2026 | Aug 10, 2026 |
| First Released | Jan 12, 2013 | Jun 15, 2015 |
| Categories | ||
| Tags | — |
Similar open source alternatives
Mumble
Low-latency, open-source voice chat built for gaming — self-host your own server with no subscription required.
Discord
Chatto
A self-hosted chat application for teams and communities with video calls, voice calls, and screen sharing.
Slack
Huly
All-in-one open source platform that combines project management, CRM, chat, HR, and wiki as an alternative to Linear, Jira, Slack, and Notion.
Notion
Bytedesk
Open source AI-powered omnichannel customer service platform that combines live chat, ticketing, and team collaboration as an alternative to Slack, Zendesk, Intercom, and HubSpot.
Slack
Zulip
Open-source team chat with a unique topic-based threading model that makes it easy to follow multiple conversations.
Slack
Colanode
Open source, local-first Slack and Notion alternative that puts you in control of your data with offline support and end-to-end encryption.
Notion