head to head · open source
Buzz vs Zulip
Buzz has 33,508 GitHub stars, 4,389 forks, 3,556 open issues and last shipped yesterday. Zulip has 25,921 stars, 10,247 forks, 2,008 open issues and last shipped yesterday. Buzz leads on adoption by 29% (33,508 vs 25,921 stars). Buzz is written in Rust under Apache-2.0; Zulip is written in Python under Apache-2.0. Buzz has attracted 13% as many forks as stars, Zulip 40%. Buzz was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Buzz | Zulip | |
|---|---|---|
| GitHub stars | ★ 34K | ★ 26K |
| License | Apache-2.0 | Apache-2.0 |
| Written in | Rust | Python |
| Last push | 2026-09-17 | 2026-09-17 |
| Forks | ⑂ 4.4K | ⑂ 10K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Buzz if
- You weight community size — 34K stars and counting
- You want the Apache-2.0 license terms
- Your stack matches Rust
- You value the larger contributor base for long-term maintenance
pick Zulip if
- You want the Zulip feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Python
- You evaluated both and Zulip fits your workflow better
About Buzz
Buzz is a self hostable workspace platform where humans and AI agents collaborate in shared rooms, using a single Nostr based event log as the underlying data model. It unifies team chat, project management, and agent automation into one coherent interface, replacing fragmented tools with a unified protocol for events like messages, code patches, CI results, workflow steps, and approvals. Built in Rust and licensed under Apache 2.0, it runs as a single relay deployment per community or as a multi tenant hosted service sharing infrastructure while preserving strict community boundaries.
About Zulip
Zulip is an open source organized team chat application built on topic based threading, aimed at distributed teams that need live and asynchronous conversation in one place, and it is positioned as an open alternative to Slack.
read the full Zulip overview →
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Frequently asked questions
Is Buzz or Zulip more popular?
Buzz has 33,508 GitHub stars and Zulip has 25,921. Buzz has the larger community by that measure.
Are Buzz and Zulip free?
Both are open source. Buzz is licensed under Apache-2.0 and Zulip under Apache-2.0. Neither carries a licence fee.
What is the difference between Buzz and Zulip?
Buzz is written in Rust and Zulip in Python. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Buzz or Zulip?
Choose Buzz if you want the larger community (33,508 stars) or its Apache-2.0 licence terms. Choose Zulip if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.