Mattermost
Platform for secure collaboration across the entire software development lifecycle, can be integrated with Gitlab (alternative to Slack).
High commit volume, frequent releases and growing activity.
Commit activity more than 88% of tracked projects; popularity more than 94%. How this is calculated.
Commits, last 11 months
| Stars | 39k |
|---|---|
| Latest release | v12.0.0-rc2 · 25 Sept 2026 |
| Repo updated | 26 Sept 2026 |
| Licence | ⊘ Proprietary |
| Built with | Go, Docker, K8S |
Is Mattermost actively maintained?
Development is ongoing. The repository recorded 1768 commits over the same window, and the last three months alone account for 578 of them.
The most recent tagged release, v12.0.0-rc2, shipped within the last month — a current, installable version exists today.
Of the 46 projects we track in Communication - Custom Communication Systems, Mattermost ranks #4 by health score — in the top quarter of its category.
What Mattermost actually does
Mattermost is a self-hosted collaboration platform designed for software development workflows and secure team communication. It serves as an alternative to proprietary chat services like Slack and integrates directly with version control systems such as GitLab. The system is written in Go and packaging typically relies on containerised environments.
Best fit: Engineering teams looking for a self-hosted communication hub that integrates closely with their GitLab infrastructure and adheres to strict security requirements.
Worth knowing: The software uses a proprietary licence model for certain distributions, which may limit free access to advanced enterprise capabilities. It also requires careful resource management compared to simpler communication tools.
Deployment notes
As a containerised Go application intended for Docker and Kubernetes orchestration, deployment typically requires persistent volume storage for message histories, an external relational database, and a reverse proxy to handle TLS termination.
Links
Mattermost as a replacement for
Alternatives to Mattermost
Projects in the same categories, ordered by health score.
Communications platform that puts data protection first (alternative to Gitter.im and Slack).
Notification infrastructure for developers.
Customer communication platform (alternative to Intercom and Zendesk).
Fully-featured Matrix client for Web, iOS & Android.
Share sensitive information securely with self-destructing links that are only viewable once.
Zulip is a powerful, open source group chat application.