anchor.diff:      glib
       libxml2
       icu
  +  ] ++ lib.optionals withIntrospection [
  +    gobject-introspection
     ];
   
     cmakeFlags = [
       "-DENABLE_GTK_DOC=False"
  -  ] ++ lib.optionals introspectionSupport [
  -    "-DGOBJECT_INTROSPECTION=True"
  -    "-DICAL_GLIB_VAPI=True"
  +    "-DGOBJECT_INTROSPECTION=${if withIntrospection then "True" else "False"}"
  +    "-DICAL_GLIB_VAPI=${if withIntrospection then "True" else "False"}"
     ] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
       "-DIMPORT_ICAL_GLIB_SRC_GENERATOR=${lib.getDev buildPackages.libical}/lib/cmake/LibIcal/IcalGlibSrcGenerator.cmake"
     ];
  
positive.code:     sha256 = "sha256-gZ6IBjG5pNKJ+hWcTzXMP7yxL4he4LTklZGoC9vXra8=";
    };
  
    nativeBuildInputs = [
      cmake
      ninja
  
negative.code: , python3
  , tzdata
  , fixDarwinDylibNames
  , withIntrospection ? stdenv.buildPlatform == stdenv.hostPlatform
  , gobject-introspection
  , vala
  }:
  