Open-source alternatives to Slack

3 projects you can self-host, audit and use for free — ranked by community votes.

1. 1

   Element

   Secure messaging on the Matrix network

   Slack vs Element
2. 2

   Mattermost

   Open source platform for developer collaboration

   Slack vs Mattermost
3. 3

   Rocket.Chat

   The communications platform you can fully control

   Slack vs Rocket.Chat

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