head to head · open source
Buzz vs Spark
Buzz has 33,547 GitHub stars, 4,395 forks, 3,556 open issues and last shipped today. Spark has 604 stars, 445 forks, 7 open issues and last shipped 5 days ago. Buzz leads on adoption by 5,454% (33,547 vs 604 stars). Buzz is written in Rust under Apache-2.0; Spark is written in Java under Apache-2.0. Buzz has attracted 13% as many forks as stars, Spark 74%. 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 | Spark | |
|---|---|---|
| GitHub stars | ★ 34K | ★ 604 |
| License | Apache-2.0 | Apache-2.0 |
| Written in | Rust | Java |
| Last push | 2026-09-18 | 2026-09-13 |
| Forks | ⑂ 4.4K | ⑂ 445 |
| 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 Spark if
- You want the Spark feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Java
- You evaluated both and Spark 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 Spark
Spark ===== [Spark] is an Open Source, cross platform IM client optimized for businesses and organizations. Group Chat In line Spell Checking End to end (E2E) Message Encryption with OTR. Tabbed Conversations File Transfer Screen Capture Sharing Message translations. Combined with the [Openfire] server, [Spark] is the easiest and best alternative to using unsecure public IM networks. [Spark] an [Ignite Realtime] community project. Resources Translation: Documentation: Community: Bug Tracker: Nightly Builds: XMPP compliance: Install Download the last release from the GitHub releases page or nightly build with the …
read the full Spark overview →
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Frequently asked questions
Is Buzz or Spark more popular?
Buzz has 33,547 GitHub stars and Spark has 604. Buzz has the larger community by that measure.
Are Buzz and Spark free?
Both are open source. Buzz is licensed under Apache-2.0 and Spark under Apache-2.0. Neither carries a licence fee.
What is the difference between Buzz and Spark?
Buzz is written in Rust and Spark in Java. 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 Spark?
Choose Buzz if you want the larger community (33,547 stars) or its Apache-2.0 licence terms. Choose Spark if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.