anchor.diff:          -qmldir $out/$qtQmlPrefix \
           -docdir $out/$qtDocPrefix"
   
  -    createQmakeCache() {
  -        cat >>"$1" <<EOF
  +    NIX_CFLAGS_COMPILE+=" -DNIXPKGS_QT_PLUGIN_PREFIX=\"$qtPluginPrefix\""
  +  '';
  +
  +  postConfigure = ''
  +    qmakeCacheInjectNixOutputs() {
  +        local cache="$1/${qmakeCacheName}"
  +        if ! [ -f "$cache" ]; then return; fi
  +        echo "qmakeCacheInjectNixOutputs: $cache"
  +        cat >>"$cache" <<EOF
       NIX_OUTPUT_BIN = $bin
       NIX_OUTPUT_DEV = $dev
       NIX_OUTPUT_OUT = $out
  
positive.code:     }
  
      find . -name '.qmake.conf' | while read conf; do
          cache=$(dirname $conf)/.qmake.cache
          echo "Creating \`$cache'"
          createQmakeCache "$cache"
      done
  
      NIX_CFLAGS_COMPILE+=" -DNIXPKGS_QT_PLUGIN_PREFIX=\"$qtPluginPrefix\""
    '';
  
  
    NIX_CFLAGS_COMPILE =
      [
  
negative.code: 
  let
    compareVersion = v: builtins.compareVersions version v;
    qmakeCacheName =
      if compareVersion "5.12.4" >= 0 then ".qmake.stash" else ".qmake.cache";
  in
  
  stdenv.mkDerivation {
  