Mattermost
Active Mixed or custom
Mattermost is an open source platform for secure collaboration across the entire software development lifecycle.
Open-source alternative to: Slack
- GitHub stars
- 39,466
- License
- Mixed or custom
- Last code push
- Oct 29, 2026
- Latest release
- v11.7.15-rc1 · Oct 28, 2026
- Runs as
- Self-hosted web app
- Hosted plan
- Offered by the project
- Main language
- TypeScript
- Repository
- mattermost/mattermost
- Website
- mattermost.com
Is Mattermost still maintained?
Active Yes. Mattermost had a code push on Oct 29, 2026 (0 days before our last check on Oct 29, 2026), and its latest release is v11.7.15-rc1 from Oct 28, 2026.
Status is re-checked weekly from GitHub. Compare every project in the maintenance tracker →
Maintainer? Add a live status badge to your README
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Before you switch
Activity: Code pushed or a release published in the last 180 days.
License: GitHub could not identify a single standard license for this repository (often a mix of open-source and commercial parts). Read the LICENSE file before using it.
Setup: Mattermost runs on a server. You can also use the hosted plan from the project if you do not want to manage one.
Similar projects
Data from the GitHub API as of Oct 29, 2026. Stars measure GitHub popularity, not quality or number of users.