Installation with Homebrew
brew install caddy installs the single caddy binary. Run it as a background service with brew services start caddy, which reads /opt/homebrew/etc/Caddyfile (Apple Silicon; /usr/local/etc on Intel).
Local HTTPS
For development, a site address of localhost makes Caddy serve HTTPS using a locally trusted certificate authority it installs on first use. Public domains on ports 80/443 require those privileged ports (run with elevated rights).
Ad-hoc usage
Without any config, caddy file-server --listen :8080 serves the current directory, and caddy reverse-proxy --from localhost:8080 --to localhost:3000 spins up a quick proxy. Use caddy reload to apply Caddyfile edits without downtime.