anchor.diff:        '';
       };
   
  +    hostPort = mkOption {
  +      type = types.nullOr types.string;
  +      default = null;
  +      example = "8080";
  +      description = ''
  +        Allow port forwarding from the host to the container. 
  +      '';
  +    };
  +
  +
       hostAddress = mkOption {
         type = types.nullOr types.str;
         default = null;
  
positive.code:         --setenv LOCAL_ADDRESS="$LOCAL_ADDRESS" \
          --setenv HOST_ADDRESS6="$HOST_ADDRESS6" \
          --setenv LOCAL_ADDRESS6="$LOCAL_ADDRESS6" \
          --setenv PATH="$PATH" \
          ${if cfg.additionalCapabilities != null && cfg.additionalCapabilities != [] then
            ''--capability="${concatStringsSep " " cfg.additionalCapabilities}"'' else ""
  
negative.code:               ${optionalString (cfg.hostBridge != null) ''
                  HOST_BRIDGE=${cfg.hostBridge}
                ''}
                ${optionalString (cfg.hostPort != null) ''
                  HOST_PORT=${cfg.hostPort}
                ''}
                ${optionalString (cfg.hostAddress != null) ''
                  HOST_ADDRESS=${cfg.hostAddress}
                ''}
  