anchor.diff:          })
         ];
       };
  -    environment.etc."mpd.conf" = {
  -      mode = "0640";
  -      group = cfg.group;
  -      user = cfg.user;
  -      # To be modified by the service' ExecStartPre
  -      text = ''
  -      '';
  -    };
   
       users.users = optionalAttrs (cfg.user == name) {
         ${name} = {
  
positive.code:   uid = config.ids.uids.mpd;
    gid = config.ids.gids.mpd;
    cfg = config.services.mpd;
  
    mpdConf = pkgs.writeText "mpd.conf" ''
      # This file was automatically generated by NixOS. Edit mpd's configuration
  
negative.code:           The path to MPD's database. If set to <literal>null</literal> the
            parameter is omitted from the configuration.
          '';
        };
  
        credentials = mkOption {
          type = types.listOf (types.submodule {
            options = {
              passwordFile = mkOption {
                type = types.path;
                description = ''
                  Path to file containing the password.
                '';
              };
              permissions = let
                perms = ["read" "add" "control" "admin"];
              in mkOption {
                type = types.listOf (types.enum perms);
                default = [ "read" ];
                description = ''
                  List of permissions that are granted with this password.
                  Permissions can be "${concatStringsSep "\", \"" perms}".
                '';
              };
            };
          });
          description = ''
            Credentials and permissions for accessing the mpd server.
          '';
          default = [];
          example = [
            {passwordFile = "/var/lib/secrets/mpd_readonly_password"; permissions = [ "read" ];}
            {passwordFile = "/var/lib/secrets/mpd_admin_password"; permissions = ["read" "add" "control" "admin"];}
          ];
        };
  
        credentialsFile = mkOption {
  