anchor.diff:  
     src = fetchurl {
       url = "mirror://gnome/sources/gtk+/${stdenv.lib.versions.majorMinor version}/gtk+-${version}.tar.xz";
  -    sha256 = "0llgq2adzn9p3bfq9rv2dhscmvzs35jp3glrfvy3vs1mrpknmsmf";
  +    sha256 = "1cg2vbwbcp7bc84ky0b69ipgdr9djhspnf5k8lajb8jphcj4v1jx";
     };
   
     patches = [
  
positive.code:   NIX_CFLAGS_COMPILE = "-DG_ENABLE_DEBUG -DG_DISABLE_CAST_CHECKS";
  
    postPatch = ''
      # TODO: Remove in 3.24.21
      # https://gitlab.gnome.org/GNOME/gtk/issues/2669
      echo "${stdenv.shell}" > check-version.py
      chmod +x check-version.py
  
      files=(
        build-aux/meson/post-install.py
        demos/gtk-demo/geninclude.py
  
negative.code: , epoxy
  , json-glib
  , libxkbcommon
  , libxml2
  , gmp
  , gnome3
  , gsettings-desktop-schemas
  