anchor.diff:          description = ''
             Extra directives added to to the end of MPD's configuration file,
             mpd.conf. Basic configuration like file location and uid/gid
  -          is added automatically to the beginning of the file.
  +          is added automatically to the beginning of the file. For available
  +          options see <literal>man 5 mpd.conf</literal>'.
           '';
         };
   
         dataDir = mkOption {
           type = types.path;
  -        default = "/var/lib/mpd";
  +        default = "/var/lib/${name}";
           description = ''
             The directory where MPD stores its state, tag cache,
             playlists etc.
  
positive.code: 
        user = mkOption {
          type = types.str;
          default = "mpd";
          description = "User account under which MPD runs.";
        };
  
        group = mkOption {
          type = types.str;
          default = "mpd";
          description = "Group account under which MPD runs.";
        };
  
  
negative.code: with lib;
  
  let
  
    name = "mpd";
  
    uid = config.ids.uids.mpd;
    gid = config.ids.gids.mpd;
  