Mattermost

Custom license

A secure messaging platform for teams that you can self-host.

Open source alternative toSlackMicrosoft Teams

View repository Website

Good to know

  • This repository was renamed on GitHub. It used to be mattermost/mattermost-server and mattermost/platform.
  • Its license file mentions Apache-2.0, but GitHub could not match the repository to one standard license, so other terms may apply to parts of it. Read the file.

TypeWeb app

JobTeam chat

Topicscollaborationgolangmattermostmonoreporeactreact-nativecustom

Sourcemattermost/mattermost on GitHub

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About these numbers. Stars, dates and licenses come from GitHub through ecosyste.ms, collected on 10 Nov 2026; they can lag GitHub by a few days. A project is listed only if it has 300 or more stars, was updated in the last 12 months and states a license. A listing is not an endorsement, and we have not tested these tools on Antideploy yet. Logos belong to their projects and companies and are shown only to say which is which.

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