anchor.diff:  
     src = fetchurl {
       url = "mirror://gnome/sources/${pname}/${lib.versions.majorMinor version}/${pname}-${version}.tar.xz";
  -    sha256 = "6hUqJD9qQ8DgNqKMcN4/y83qVmTGgRx4WSvCKezCSDM=";
  +    sha256 = "bmJsVk41S82MOEuQ+OTzCzA6+mweDLXMVroUkAxdtzA=";
     };
   
  -  cargoVendorDir = "vendor";
  +  cargoDeps = rustPlatform.fetchCargoTarball {
  +    inherit src;
  +    name = "${pname}-${version}";
  +    hash = "sha256-tvfdRGyrEkEh6sb69f0ugfzR2bgGdWa05pSyovpXAF8=";
  +    # TODO: move this to fetchCargoTarball
  +    dontConfigure = true;
  +  };
   
     strictDeps = true;
   
  
positive.code: , withIntrospection ? stdenv.hostPlatform == stdenv.buildPlatform
  , gobject-introspection
  , nixosTests
  }:
  
  stdenv.mkDerivation rec {
    pname = "librsvg";
    version = "2.54.4";
  
    outputs = [ "out" "dev" "installedTests" ] ++ lib.optionals withIntrospection [
      "devdoc"
  
negative.code:   '';
  
    passthru = {
      updateScript =
        let
          updateSource = gnome.updateScript {
            packageName = "librsvg";
            versionPolicy = "odd-unstable";
          };
  
          updateLockfile = {
            command = [
              "sh"
              "-c"
              ''
                PATH=${lib.makeBinPath [
                  common-updater-scripts
                  jq
                  nix
                ]}
                # update-source-version does not allow updating to the same version so we need to clear it temporarily.
                # Get the current version so that we can restore it later.
                latestVersion=$(nix-instantiate --eval -A librsvg.version | jq --raw-output)
                # Clear the version. Provide hash so that we do not need to do pointless TOFU.
                # Needs to be a fake SRI hash that is non-zero, since u-s-v uses zero as a placeholder.
                # Also cannot be here verbatim or u-s-v would be confused what to replace.
                update-source-version librsvg 0 "sha256-${lib.fixedWidthString 44 "B" "="}" --source-key=cargoDeps > /dev/null
                update-source-version librsvg "$latestVersion" --source-key=cargoDeps > /dev/null
              ''
            ];
            # Experimental feature: do not copy!
            supportedFeatures = [ "silent" ];
          };
        in
        _experimental-update-script-combinators.sequence [
          updateSource
          updateLockfile
        ];
  
      tests = {
        installedTests = nixosTests.installed-tests.librsvg;
  