Mattermost
An open core team chat platform with channels, workflow automation, calls and screen sharing, aimed at engineering and security teams.
What is Mattermost?
Mattermost combines team chat with workflow automation, voice calls, screen sharing and AI integrations. The server is written in Go and React, runs as a single Linux binary and stores its data in PostgreSQL; you can install it with Docker, on Ubuntu, from a tarball or on Kubernetes. Desktop apps for Windows, macOS and Linux and mobile apps for Android and iOS connect to it, and webhooks, slash commands, plugins and more than 700 integrations extend it. Its main use cases are DevSecOps, incident resolution and IT service desks.
Good fit if
- Your engineering or security team wants a self-hosted Slack replacement next to its other tools.
- You prefer one binary and a PostgreSQL database to a large set of services in production.
- Your users need another language: the interface is translated into 25.
Look elsewhere if
- You want the whole repository under an open license, with no enterprise directory: Zulip.
- You also chat with customers and other companies: Rocket.Chat.
Before you adopt it
Mattermost calls itself open core. Its source is Apache-2.0, while the server/enterprise directory falls under the Mattermost Source Available License and its features need a paid license. Compiled releases come out every month on the 16th under an MIT license. The development setup starts 18 services, including MinIO, Elasticsearch and Redis.
Drafted with AI from the project's README and repository data, then checked against that data on 31 October 2026. Report a correction
Mattermost health: is it still maintained?
74 of 100, actively developed
Read from GitHub on 1 November 2026. How the score works
Mattermost license: is it open source?
Mattermost uses Apache-2.0, an open-source license approved by the OSI. Some features sit under a separate paid license inside the same repository.
- June 2015First published on GitHub.
- TodayApache-2.0, with paid parts: directory server/enterprise/; separate license LICENSE.enterprise; separate license server/enterprise/LICENSE (The Mattermost Source Available License).
How to run Mattermost yourself
- Docker
- Dockerfile or compose file in the repository
- Compose file
- server/docker-compose.yaml: 18 services (postgres, minio, elasticsearch, redis, proxy)
- Setup effort
- 5 of 5, judged from the compose file
- Kubernetes
- No Helm chart in the repository
- Desktop and mobile
- No app builds in GitHub releases
- Interface languages
- 25 languages
Install instructions: mattermost.com or the README on GitHub.
Alternatives to Mattermost
- Rocket.ChatThe Secure CommsOS™ for mission-critical operations 82 health · MIT · 46.4k stars
- ZulipZulip server and web application. Open-source team chat that helps teams stay productive and focused. 92 health · Apache-2.0 · 26.2k stars
Questions about Mattermost
Is Mattermost open source?
Yes. Mattermost is published under Apache-2.0, an OSI-approved open-source license. Some features are kept under a separate paid license in the same repository.
Is Mattermost still maintained?
Its health score is 74 of 100 (actively developed). It had 747 commits in the last 90 days, the latest on 1 November 2026, and its latest release came out on 22 October 2026.
How do I run Mattermost?
You can run it with Docker. The README on GitHub has the exact steps.
What are the alternatives to Mattermost?
Close alternatives in the Team chat category include Rocket.Chat, Zulip.