Rocket.Chat vs Zulip: which one to choose in 2026?
Both are open source alternatives to Slack. We compare license, tech stack and features to help you decide which fits your team best.
| Rocket.Chat | Zulip | |
|---|---|---|
| Category | Productivity | Productivity |
| License | MIT | Apache-2.0 |
| GitHub stars | 41k | 21k |
| Tech stack | Node.js, Meteor, MongoDB | Python, Django, PostgreSQL |
| Replaces | Slack | Slack |
Rocket.Chat has more GitHub stars, which usually indicates a larger community (not necessarily that it's the best option for your use case).
Rocket.Chat
Self-hostable team chat, an alternative to Slack.
Pros
- MIT license
- No message history limit
Things to consider
- MongoDB with a replica set adds operational complexity
Zulip
Team chat organized by threads, an alternative to Slack.
Pros
- Much less noise than Slack in very active channels
Things to consider
- The topic-thread model has a learning curve
Key features
Rocket.Chat
- Native channels, threads and video calls
- Bridging with Matrix, Slack and WhatsApp
- Apps and bots via the Rocket.Chat Marketplace
Zulip
- Topic threads within each channel
- Powerful search across the whole history
- Native cross-platform apps