Zulip
Organized team chat with topic-based threading
25.6k stars 10k forks last commit first released Apache-2.0
Actively maintained
Last commit 27 Jul 2026.
Zulip is an open-source team chat platform designed for both real-time and asynchronous communication. Its distinctive topic-based threading keeps conversations organized, making it easier to follow multiple discussions without losing context.
Key Features
- Topic-based threading within channels (streams) to keep discussions focused
- Inbox-style view to prioritize unread conversations
- Real-time messaging with searchable history
- Powerful integrations and bots, including webhook-based workflows
- Granular permissions and administration for organizations and communities
- Multi-platform clients, including web, desktop, and mobile apps
Use Cases
- Team communication for engineering, product, and operations groups
- Open source or community collaboration with many parallel discussions
- Async-first coordination across time zones while preserving context
Zulip is a strong fit for teams that want the immediacy of chat without sacrificing long-term clarity. Its conversation organization model scales well as the number of channels and active threads grows.
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