anchor.diff:        default = false;
         # getEnv part is in check-meta.nix
         defaultText = literalExpression ''false || builtins.getEnv "NIXPKGS_ALLOW_UNFREE" == "1"'';
  -      description = ''
  +      description = lib.mdDoc ''
           Whether to allow unfree packages.
   
  -        See <link xlink:href="https://nixos.org/manual/nixpkgs/stable/#sec-allow-unfree">Installing unfree packages</link> in the NixOS manual.
  +        See [Installing unfree packages](https://nixos.org/manual/nixpkgs/stable/#sec-allow-unfree) in the NixOS manual.
         '';
       };
   
  
positive.code:   mkMassRebuild = args: mkOption (builtins.removeAttrs args [ "feature" ] // {
      type = args.type or (types.uniq types.bool);
      default = args.default or false;
      description = (args.description or ''
        Whether to ${args.feature} while building nixpkgs packages.
      '') + ''
        Changing the default may cause a mass rebuild.
      '';
    });
  
    options = {
  
negative.code:     /* Config options */
  
      warnUndeclaredOptions = mkOption {
        description = lib.mdDoc "Whether to warn when `config` contains an unrecognized attribute.";
        type = types.bool;
        default = false;
      };
  
      doCheckByDefault = mkMassRebuild {
        feature = "run `checkPhase` by default";
      };
  
      strictDepsByDefault = mkMassRebuild {
        feature = "set `strictDeps` to true by default";
      };
  
      enableParallelBuildingByDefault = mkMassRebuild {
        feature = "set `enableParallelBuilding` to true by default";
      };
  
      configurePlatformsByDefault = mkMassRebuild {
        feature = "set `configurePlatforms` to `[\"build\" \"host\"]` by default";
      };
  
      contentAddressedByDefault = mkMassRebuild {
        feature = "set `__contentAddressed` to true by default";
      };
  
      allowAliases = mkOption {
        type = types.bool;
        default = true;
        description = lib.mdDoc ''
          Whether to expose old attribute names for compatibility.
  
          The recommended setting is to enable this, as it
  