anchor.diff:        description = ''
           A list of additional packages supplying kernel modules.
         '';
  -      merge = name: list:
  -        pkgsArg: pkgs.lib.concatMap (f: f pkgsArg) list;
  +      merge = backwardPkgsFunListOldMerge;
       };
   
       kernelModules = mkOption {
  
positive.code: 
      extraFonts = mkOption {
        default = pkgs: [];
        description = "
            Function, returning list of additional fonts.
        ";
  
negative.code: 
        packageFun = mkOption {
          default = pkgs: pkgs.xorg;
          merge = backwardPkgsFunOldMerge;
          description = "
            Alternative X.org package to use. For 
            example, you can replace individual drivers.
  