Open-source projects tagged “slack”

Open-source and self-hostable projects tagged “slack” on GitHub, with license, free-edition limits and setup checked against official sources.

Rocket.Chat
A self-hostable team communications platform with chat, channels, and omnichannel customer messaging.
Stars46k
Last commitOct 10, 2026
LicenseMIT
Zulip
A self-hostable team chat app that organizes every conversation into topics inside channels.
Stars26k
Last commitOct 9, 2026
LicenseApache-2.0