anchor.diff:      optionals
       optionalString;
   
  -  channel = "1.56";
  -  version = "${channel}.1";
  +  channel = "1.58";
  +  version = "${channel}.0";
   in
   stdenv.mkDerivation rec {
     name = "gobject-introspection-${version}";
  
positive.code: , fetchurl
  , flex
  , lib
  # , meson
  # , ninja
  
  , bzip2
  , glib
  , libffi
  , python2
  
  , cairo
  }:
  
negative.code:     })
    ];
  
    postPatch = ''
      # Fix python patching
      grep -q 's,@PYTHON_CMD\\@,.*$(PYTHON),' Makefile.in
      sed -i 's#s,@PYTHON_CMD\\@,.*$(PYTHON),#s,@PYTHON_CMD\\@,$(PYTHON),#' Makefile.in
    '';
  
    configureFlags = [
      "--disable-maintainer-mode"
      "--disable-gtk-doc"
      "--disable-doctool"
    ];
  
    doCheck = false;
  
    passthru = {
      srcVerification = fetchurl {
        failEarly = true;
        inherit (src)
          outputHash
          outputHashAlgo
          urls;
        fullOpts = {
          sha256Url = "https://download.gnome.org/sources/gobject-introspection/"
            + "${channel}/${name}.sha256sum";
        };
      };
    };
  
  