anchor.diff:    src = fetchurl {
       url = "https://github.com/libass/libass/releases/download/${version}/"
         + "${name}.tar.xz";
  -    sha256 = "7065e5f5fb76e46f2042a62e7c68d81e5482dbeeda24644db1bd066e44da7e9d";
  +    sha256 = "881f2382af48aead75b7a0e02e65d88c5ebd369fe46bc77d9270a94aa8fd38a2";
     };
   
     nativeBuildInputs = [
  
positive.code:   ];
  
    configureFlags = [
      "--${boolEn doCheck}-test"
      "--disable-profile"
      "--${boolEn (fontconfig != null)}-fontconfig"
      "--disable-directwrite" # Windows
      "--disable-coretext" # OSX
      "--enable-require-system-font-provider"
      "--${boolEn (harfbuzz_lib != null)}-harfbuzz"
      "--${boolEn (nasm != null)}-asm"
      "--${boolEn rasterizerSupport}-rasterizer"
      "--${boolEn largeTilesSupport}-large-tiles"
    ];
  
    doCheck = false;
  
    meta = with stdenv.lib; {
      description = "Library for SSA/ASS subtitles rendering";
  
negative.code:   inherit (stdenv.lib)
      boolEn;
  
    version = "0.14.0";
  in
  stdenv.mkDerivation rec {
    name = "libass-${version}";
  