anchor.diff:  
   stdenv.mkDerivation rec {
     pname = "librsvg";
  -  version = "2.52.6";
  +  version = "2.53.1";
   
  -  outputs = [ "out" "dev" "installedTests" ];
  +  outputs = [ "out" "dev" "installedTests" ] ++ lib.optionals withIntrospection [
  +    "devdoc"
  +  ];
   
     src = fetchurl {
       url = "mirror://gnome/sources/${pname}/${lib.versions.majorMinor version}/${pname}-${version}.tar.xz";
  -    sha256 = "o/k5oeajpgQIJEYy0DI/jDsg60t7AAU24uW9k7jv+q0=";
  +    sha256 = "uo4EAHR0nzhFRFxWAuCQLzAHoYsHTPDMahDI3cWmUyI=";
     };
   
     cargoVendorDir = "vendor";
  
positive.code:     mv $GDK_PIXBUF/loaders.cache.tmp $GDK_PIXBUF/loaders.cache
    '';
  
    passthru = {
      updateScript = gnome.updateScript {
        packageName = pname;
  
negative.code: , rustc
  , rust
  , cargo
  , gi-docgen
  , python3
  , gnome
  , vala
  , withIntrospection ? stdenv.hostPlatform == stdenv.buildPlatform
  