yuk.nu.conf.erb

server {
  listen       80;
  server_name  <%= domain.name %>;

  location ~* ^/[a-z0-9]+/?$ {
    proxy_pass <%= domain.upstream %>;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
  }

  location / {
    return    301 https://$server_name$request_uri;
  }

  <%= acme_challenge_location %>
}