anchor.diff: -{ stdenv, fetchFromGitHub, pkgconfig, autoreconfHook
  +{ stdenv, fetchFromGitHub, pkgconfig, autoreconfHook, makeWrapper
   , zimg, libass, python3, libiconv
   , ApplicationServices, nasm
   , ocrSupport ?  false, tesseract ? null
  
positive.code: with stdenv.lib;
  
  stdenv.mkDerivation rec {
    name = "vapoursynth-${version}";
    version = "R46";
  
    src = fetchFromGitHub {
  
negative.code:     sha256 = "1xbwva12l68awplardf47ydlx904wifw468npaxa9cx9dvd5mv13";
    };
  
    nativeBuildInputs = [ pkgconfig autoreconfHook nasm makeWrapper ];
    buildInputs = [
      zimg libass
      (python3.withPackages (ps: with ps; [ sphinx cython ]))
  