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:     extraPackages = mkOption {
        default = pkgs: [];
        example = pkgs: [pkgs.firefox pkgs.thunderbird];
        merge = backwardPkgsFunListOldMerge;
        description = "
          This option allows you to add additional packages to the system
          path.  These packages are automatically available to all users,
  