Caddy: the web server with automatic HTTPS

caddyserver/caddy (about 78,000 stars) is a production web server whose defining feature is that HTTPS is on by default: name a domain in the configuration and Caddy gets a certificate from Let’s Encrypt or ZeroSSL, redirects HTTP to HTTPS, staples OCSP responses and renews everything before it expires, with no cron jobs or external tools. It serves static files, acts as a reverse proxy and load balancer, terminates TLS for other services, and speaks HTTP/3. It is a single static binary with no dependencies, released under the Apache 2.0 license.

Use it when you want a small server, a home lab or a side project online over HTTPS in minutes without learning certificate tooling; when you run several apps behind one IP and want a few lines per site; or as the TLS front door in a Docker Compose stack. Its reverse_proxy directive handles WebSockets, forwarded headers, health checks and multiple backends without extra directives. Where Nginx is the right choice for very large deployments with deep tuning and a huge pool of existing examples, Caddy wins on time to a working, secure setup. Its configuration is also available as JSON and through a live REST API, which makes it scriptable.

Install it from the official package repositories for Debian, Ubuntu, Fedora and RHEL as described on the install page, with brew install caddy on macOS, or run the caddy Docker image. Then put a Caddyfile at /etc/caddy/Caddyfile such as example.com { reverse_proxy localhost:3000 } and systemctl reload caddy. For a quick local try, caddy file-server --listen :8080 serves the current folder and caddy reverse-proxy --from localhost:8443 --to localhost:3000 fronts a dev server with a locally trusted certificate. Plugins (DNS providers for wildcard certificates, rate limiting, and more) are compiled in with the xcaddy tool or downloaded prebuilt from the website.

Caddy was created by Matt Holt in 2015 and is maintained by him and a group of core contributors with sponsorship from several companies; the community forum at caddy.community is active and the documentation is unusually clear.