head to head · open source
Sentry vs defmt
Sentry has 44,806 GitHub stars, 4,857 forks, 2,265 open issues and last shipped today. defmt has 1,229 stars, 132 forks, 117 open issues and last shipped 12 days ago. Sentry leads on adoption by 3,546% (44,806 vs 1,229 stars). Sentry is written in Python under a custom or non-standard licence; defmt is written in Rust under Apache-2.0. Sentry has attracted 11% as many forks as stars, defmt 11%. Sentry 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
| Sentry | defmt | |
|---|---|---|
| GitHub stars | ★ 45K | ★ 1.2K |
| License | Custom / other | Apache-2.0 |
| Written in | Python | Rust |
| Last push | 2026-09-20 | 2026-09-08 |
| Forks | ⑂ 4.9K | ⑂ 132 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Sentry if
- You weight community size — 45K stars and counting
- You want the Custom / other license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick defmt if
- You want the defmt 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 defmt fits your workflow better
About Sentry
Sentry is an open source debugging platform for detecting, tracing, and fixing software issues in real time. It lives in the developer infrastructure ecosystem and provides error tracking and performance monitoring across languages, frameworks, and runtime environments.
read the full Sentry overview →
About defmt
defmt is an efficient, deferred formatting logging framework for embedded systems written in Rust, aimed at firmware developers building for resource constrained devices such as microcontrollers.
read the full defmt overview →
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Frequently asked questions
Is Sentry or defmt more popular?
Sentry has 44,806 GitHub stars and defmt has 1,229. Sentry has the larger community by that measure.
Are Sentry and defmt free?
Both are open source. Sentry has no licence declared in this registry, and defmt is licensed under Apache-2.0. Both are free to self-host.
What is the difference between Sentry and defmt?
Sentry is written in Python and defmt 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, Sentry or defmt?
Choose Sentry if you want the larger community (44,806 stars) or its Custom / other licence terms. Choose defmt if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.