anchor.diff:      ++ optional speexSupport       speex
       ++ optional bs2bSupport        libbs2b
       ++ optional openalSupport      openalSoft
  -    ++ optional (openalSupport && stdenv.isDarwin) darwin.apple_sdk.frameworks.OpenAL
       ++ optional libpngSupport      libpng
       ++ optional youtubeSupport     youtube-dl
       ++ optional sdl2Support        SDL2
  
positive.code:     sha256 = "0i2nl65diqsjyz28dj07h6d8gq6ix72ysfm0nhs8514hqccaihs3";
    };
  
    postPatch = ''
      patchShebangs ./TOOLS/
    '';
  
negative.code: { stdenv, fetchpatch, fetchurl, fetchFromGitHub, makeWrapper
  , docutils, perl, pkgconfig, python3, which, ffmpeg_4
  , freefont_ttf, freetype, libass, libpthreadstubs
  , lua, luasocket, libuchardet, libiconv ? null, darwin
  