head to head · open source
Buzz vs Spark
Buzz has 36,686 GitHub stars, 4,869 forks, 3,556 open issues and last shipped yesterday. Spark has 606 stars, 445 forks, 7 open issues and last shipped 2 days ago. Buzz leads on adoption by 5,954% (36,686 vs 606 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 73%. 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.
← all 20902 open source comparisons
Side by side
| Buzz | Spark | |
|---|---|---|
| GitHub stars | ★ 37K | ★ 606 |
| License | Apache-2.0 | Apache-2.0 |
| Written in | Rust | Java |
| Last push | 2026-11-02 | 2026-11-01 |
| Forks | ⑂ 4.9K | ⑂ 445 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Buzz if
- You weight community size — 37K 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 🐝 A workspace where humans and agents build together, on a relay you own. Vision · Sovereign · Forge · Agents · Architecture · Releasing · Apache 2.0 People and agents building together in the same room. What is this, really? Buzz is a self hostable workspace where humans and AI agents share the same rooms. A Buzz community is the workspace a user reaches by URL. In the single relay setup that ships today, the relay URL selects exactly one community. A hosted operator can serve many communities behind many domains or subdomains, but the client facing rule stays the same: the URL is authoritative for the…
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 →
More in Business Software
Related comparisons
More Collaboration & Communication projects
Compare either of these against the rest of the Collaboration & Communication field.
Frequently asked questions
Is Buzz or Spark more popular?
Buzz has 36,686 GitHub stars and Spark has 606. 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 (36,686 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.