anchor.diff:      propagatedBuildInputs = depends;
       nativeBuildInputs = depends;
       meta.homepage = mkHomepage (args // { inherit name; });
  -    meta.platforms = R.meta.platforms;
  +    meta.platforms = platforms;
       meta.hydraPlatforms = hydraPlatforms;
       meta.broken = broken;
       meta.maintainers = maintainers;
  
positive.code:   #
    # some packages, e.g. cncaGUI, require X running while installation,
    # so that we use xvfb-run if requireX is true.
    mkDerive = {mkHomepage, mkUrls, hydraPlatforms ? R.meta.platforms}: args:
      let hydraPlatforms' = hydraPlatforms; in
        lib.makeOverridable ({
          name, version, sha256,
  
negative.code:         doCheck ? true,
          requireX ? false,
          broken ? false,
          platforms ? R.meta.platforms,
          hydraPlatforms ? if hydraPlatforms' != null then hydraPlatforms' else platforms,
          maintainers ? []
        }: buildRPackage {
      name = "${name}-${version}";
  