fly-apps/static/Caddyfile

{
  # fly.io handles HTTPS for us
  auto_https off
}

http://static-mat-services.fly.dev/ {
  redir https://mat.services/
}

:8080 {
  root * /var/www
  file_server

  handle_errors {
    @404 {
      expression {http.error.status_code} == 404
    }
    rewrite @404 /404.html
    file_server
  }
}