head to head · open source
Uptime Kuma vs defmt
Uptime Kuma has 93,190 GitHub stars, 8,655 forks, 805 open issues and last shipped yesterday. defmt has 1,241 stars, 135 forks, 117 open issues and last shipped yesterday. Uptime Kuma leads on adoption by 7,409% (93,190 vs 1,241 stars). Uptime Kuma is written in JavaScript under MIT; defmt is written in Rust under Apache-2.0. Uptime Kuma has attracted 9% as many forks as stars, defmt 11%. Uptime Kuma 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
| Uptime Kuma | defmt | |
|---|---|---|
| GitHub stars | ★ 93K | ★ 1.2K |
| License | MIT | Apache-2.0 |
| Written in | JavaScript | Rust |
| Last push | 2026-11-02 | 2026-11-02 |
| Forks | ⑂ 8.7K | ⑂ 135 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Uptime Kuma if
- You weight community size — 93K stars and counting
- You want the MIT license terms
- Your stack matches JavaScript
- 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 Uptime Kuma
Uptime Kuma Uptime Kuma is an easy to use self hosted monitoring tool. 🥔 Live Demo Try it! Demo Server (Location: Frankfurt Germany): It is a temporary live demo, all data will be deleted after 10 minutes. Sponsored by Uptime Kuma Sponsors. ⭐ Features Monitoring uptime for HTTP(s) / TCP / HTTP(s) Keyword / HTTP(s) Json Query / Websocket / Ping / DNS Record / Push / Steam Game Server / Docker Containers Fancy, Reactive, Fast UI/UX Notifications via Telegram, Discord, Gotify, Slack, Pushover, Email (SMTP), and 90+ notification services, click here for the full list 20 second intervals Multi Languages Multiple…
read the full Uptime Kuma overview →
About defmt
defmt defmt ("de format", short for "deferred formatting") is a highly efficient logging framework that targets resource constrained devices, like microcontrollers. For more details about the framework check the book at . Components This repository contains the following packages: MSRV The minimum supported Rust version is 1.76 (or Ferrocene 24.05) for the crates that cross compile to your microcontroller. The minimum supported Rust version is 1.83 for all host side crates. The defmt crates are tested against the latest stable Rust version and the MSRV. Developer Information Running Tests Tests are run using…
read the full defmt overview →
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Frequently asked questions
Is Uptime Kuma or defmt more popular?
Uptime Kuma has 93,190 GitHub stars and defmt has 1,241. Uptime Kuma has the larger community by that measure.
Are Uptime Kuma and defmt free?
Both are open source. Uptime Kuma is licensed under MIT and defmt under Apache-2.0. Neither carries a licence fee.
What is the difference between Uptime Kuma and defmt?
Uptime Kuma is written in JavaScript 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, Uptime Kuma or defmt?
Choose Uptime Kuma if you want the larger community (93,190 stars) or its MIT licence terms. Choose defmt if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.