Caddy is good, especially for super simple static sites. As soon as it gets somewhat complex, the configs start becoming messy and opaque, eg.

Nginx:

    rewrite ^/old/((\w|-)+) /new/$1.php;
 

Caddy:

    @oldPath {
        path_regexp old ^/old/([\w-]+)
    }

    rewrite @oldPath /new/{re.old.1}.php

And many things are not even handled by Caddy, or fail silently (for example, we could not get NetData to reverse_proxy behind Caddy no matter what we tried, and the logs were completely useless.)