anchor.diff:  
     enableParallelBuilding = true;
   
  +  # Required by Poppler
  +  # https://github.com/jwilk/pdf2djvu/commit/373e065faf2f0d868a3700788d20a96e9528bb12
  +  CXXFLAGS = "-std=c++17";
  +
     meta = with lib; {
       description = "Creates djvu files from PDF files";
       homepage = "https://jwilk.net/software/pdf2djvu";
  
positive.code: }:
  
  stdenv.mkDerivation rec {
    version = "0.9.17.1";
    pname = "pdf2djvu";
  
    src = fetchFromGitHub {
      owner = "jwilk";
      repo = "pdf2djvu";
      rev = version;
      sha256 = "1igabfy3fd7qndihmkfk9incc15pjxpxh2cn5pfw5fxfwrpjrarn";
    };
  
    patches = [
      # Not included in 0.9.17.1, but will be in the next version.
      (fetchpatch {
        name = "no-poppler-splash.patch";
        url = "https://github.com/jwilk/pdf2djvu/commit/2ec7eee57a47bbfd296badaa03dc20bf71b50201.patch";
        sha256 = "03kap7k2j29r16qgl781cxpswzg3r2yn513cqycgl0vax2xj3gly";
      })
    ];
  
    nativeBuildInputs = [ autoreconfHook pkg-config ];
  
  
negative.code: { stdenv
  , lib
  , fetchFromGitHub
  , autoreconfHook
  , gettext
  , libtool
  