Alternatives directory
2 Open Source Alternatives to Slack
Hand-picked chat & communication tools you can self-host instead of Slack
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Teams leave Slack for many reasons: cost, data residency, vendor lock-in, or the need to run software on their own servers. Below are 2 open source projects that people actually use in place of Slack. Mattermost currently leads this list with about 39,232 GitHub stars, which is a useful signal of community activity (not a guarantee of fit for every team). Another option worth a look is Rocket.Chat. Licenses in this set include AGPL-3.0, MIT. Most of these projects sit in the chat & communication tools space.
When you compare alternatives to Slack, look past marketing pages. Check how often the repo ships commits, how clear the install docs are, and whether the license matches how you plan to deploy (including SaaS or internal use). Primary languages among these projects include TypeScript. That matters if your team already standardizes on a stack for operations and security review. Use the cards below to open full profiles, Docker notes, and community pros and cons for each project.
What Slack is known for
- Channels
- Direct messages
- Integrations
- Search
2 alternatives to explore
Sorted by health score. Names in the overview above also link to full profiles.