"Caddy was born out of the need for a "batteries-included" web server that runs anywhere and doesn't have to take its configuration with it. Caddy took inspiration from spark, nginx, lighttpd, Websocketd and Vagrant, which provides a pleasant mixture of features from each of them."

Caddy is a web server written in Go. Golang is a high performance computer language designed by Google. Go have owner concurrency model (Goroutine), CPU scalability and garbage-collected. It has a number of software written in Go.

Pros Cons
Simple Performance
Free for personal and non-profit organizations Not free for commercial (start only 25/instance/mo
Variety platforms (Windows, Mac, Linux, Android, ARM,...)
Modern feature (HTTP/2, QUIC, brotli)
HTTPS built-in (Let's Encrypt)
open source

Performance

performance testing by 相關文章
performance testing by eva2000 (community.centminmod.com)

Conclusion

Caddy’s primary goal is easy-to-use, HTTPS by default and come with modern feature (HTTP/2, QUIC). It good for developer and small website. For performance it can serve up to 30,000 req/sec depend on hardware. However I think for large traffic website, Nginx still best.

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