Dynamic proxy upstream

[johnnypea]

Is something like this possible, please?

{
    layer4 {
        :80 {
            @site http host *.caddy.example.com
            route @site {
                subroute {
                    @insecure http
                    route @insecure {
                        proxy {labels.3}.incus:80
                    }
                }
            }
        }
    }
}

How can I match part of the domain and use it in proxy directive?

[vnxme]

I think, you can use vars_regexp with {http.request.host} of the mainline Caddy instead, and you may do without caddy-l4 at all.