NIX_REMOTE_SYSTEMS = concatStringsSep ":" cfg.buildMachinesFiles;

      buildMachinesFiles = mkOption {
        type = types.list types.path;
        default = [];
        example = [ "/etc/nix/machines" "/var/lib/hydra/provisioner/machines" ];
        description = "List of files containing build machines.";
      };

            WorkingDirectory = baseDir;