Open Source Team Chat Tools

Zulip

25,87810,210

Zulip is an open-source team chat application, and a self-hosted alternative to Slack. Its distinguishing feature is topic-based threading: every message in a channel belongs to a named topic, so conversations stay separable and catch-up reading is fast even in busy channels. It offers full-text search, hundreds of integrations, interactive bots, and native mobile and desktop apps.