SelfHostOffice

Mattermost

Replaces Slack

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

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Stars39,400
LicenseCustom / see repo
Last pushOct 21, 2026
Active
Forks9,061
Open issues + PRs1,083
LanguageTypeScript
GitHub topics:collaborationgolanghacktoberfestmattermostmonoreporeactreact-native

Source: https://api.github.com/repos/mattermost/mattermost, fetched Oct 21, 2026. "Active" means a push within 30 days of that fetch. Maintainer? Claim or get featured.

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