anchor.diff:  
     doCheck = false;
   
  -  meta = with stdenv.lib; {
  +  meta = with lib; {
       description = "Libraries for cryptographic UIs and accessing PKCS#11 modules";
       homepage = https://git.gnome.org/browse/gcr;
       license = with licenses; [
  
positive.code: }:
  
  let
    inherit (stdenv.lib)
      enFlag;
  in
  stdenv.mkDerivation rec {
    name = "gcr-${version}";
    versionMajor = "3.20";
    versionMinor = "0";
    version = "${versionMajor}.${versionMinor}";
  
    src = fetchurl {
      url = "mirror://gnome/sources/gcr/${versionMajor}/${name}.tar.xz";
  
negative.code:     "--disable-gtk-doc"
      "--disable-gtk-doc-html"
      "--disable-gtk-doc-pdf"
      "--enable-introspection"
      "--${boolEn (vala != null)}-vala"
      "--disable-update-mime"
      "--disable-update-icon-cache"
      "--disable-debug"
  