head to head · open source
cobalt vs Buzz
cobalt has 43,316 GitHub stars, 3,798 forks, 269 open issues and last shipped 6 months ago. Buzz has 33,508 stars, 4,389 forks, 3,556 open issues and last shipped yesterday. cobalt leads on adoption by 29% (43,316 vs 33,508 stars). cobalt is written in Svelte under AGPL-3.0; Buzz is written in Rust under Apache-2.0. cobalt has attracted 9% as many forks as stars, Buzz 13%. 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
| cobalt | Buzz | |
|---|---|---|
| GitHub stars | ★ 43K | ★ 34K |
| License | AGPL-3.0 | Apache-2.0 |
| Written in | Svelte | Rust |
| Last push | 2026-04-06 | 2026-09-17 |
| Forks | ⑂ 3.8K | ⑂ 4.4K |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick cobalt if
- You weight community size — 43K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Svelte
- You value the larger contributor base for long-term maintenance
pick Buzz if
- You want the Buzz feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Rust
- You evaluated both and Buzz fits your workflow better
About cobalt
cobalt is a media downloader built around a single promise: paste a link, get the file, move on. It is a monorepo containing the source for an API, a web frontend, and related packages, written primarily in Svelte and TypeScript. The project lives in the modern web and JavaScript ecosystem, and its public surface is hosted at cobalt.tools, while the full codebase is published under the AGPL 3.0 license.
read the full cobalt overview →
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.
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Frequently asked questions
Is cobalt or Buzz more popular?
cobalt has 43,316 GitHub stars and Buzz has 33,508. cobalt has the larger community by that measure.
Are cobalt and Buzz free?
Both are open source. cobalt is licensed under AGPL-3.0 and Buzz under Apache-2.0. Neither carries a licence fee.
What is the difference between cobalt and Buzz?
cobalt is written in Svelte and Buzz in Rust. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, cobalt or Buzz?
Choose cobalt if you want the larger community (43,316 stars) or its AGPL-3.0 licence terms. Choose Buzz if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.