head to head · open source
effect vs qtap
effect has 17,476 GitHub stars, 895 forks, 253 open issues and last shipped yesterday. qtap has 1,465 stars, 57 forks, 8 open issues and last shipped 2 days ago. effect leads on adoption by 1,093% (17,476 vs 1,465 stars). effect is written in TypeScript under MIT; qtap is written in C under Apache-2.0. effect has attracted 5% as many forks as stars, qtap 4%. effect was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 1 topic tag (observability), so they are genuine substitutes rather than adjacent tools.
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
| effect | qtap | |
|---|---|---|
| GitHub stars | ★ 17K | ★ 1.5K |
| License | MIT | Apache-2.0 |
| Written in | TypeScript | C |
| Last push | 2026-11-04 | 2026-11-03 |
| Forks | ⑂ 895 | ⑂ 57 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick effect if
- You weight community size — 17K stars and counting
- You want the MIT license terms
- Your stack matches TypeScript
- You value the larger contributor base for long-term maintenance
pick qtap if
- You want the qtap feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches C
- You evaluated both and qtap fits your workflow better
About effect
Effect Effect is a library for building robust, maintainable, type safe, and production grade applications in TypeScript. It helps you handle the hard problems at scale: typed errors, dependency injection, structured concurrency, scheduling, tracing, and unified schema validation. Effect V4 is currently a release candidate. The main branch contains v4 development. Install V4 RC Requirements TypeScript 5.9 or newer. TypeScript 7 is recommended for the best performance and compatibility with Effect's TypeScript tooling. Node.js 18 or newer is the general minimum for running Effect on Node.js. Some integration…
read the full effect overview →
About qtap
An eBPF agent that captures traffic flowing through the Linux kernel. By attaching to TLS/SSL functions, data is intercepted before and after encryption and then passed to flexible plugins with full visibility along with all of the available context process/container/host/user/protocol/etc. Qtap makes it possible to understand what's happening with your egress traffic, without modifying apps, installing proxies, or managing certs. Qtap shows you exactly what data is being sent and received in its original, unencrypted form while operating out of band with minimal overhead, without adding latency or disrupting…
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Frequently asked questions
Is effect or qtap more popular?
effect has 17,476 GitHub stars and qtap has 1,465. effect has the larger community by that measure.
Are effect and qtap free?
Both are open source. effect is licensed under MIT and qtap under Apache-2.0. Neither carries a licence fee.
What is the difference between effect and qtap?
effect is written in TypeScript and qtap in C. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, effect or qtap?
Choose effect if you want the larger community (17,476 stars) or its MIT licence terms. Choose qtap if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.