anchor.diff:  , pkg-config, cmake, doxygen
   , libopenshot-audio, imagemagick, ffmpeg
   , swig, python3, jsoncpp
  -, unittest-cpp, cppzmq, zeromq
  +, cppzmq, zeromq
   , qtbase, qtmultimedia
   , llvmPackages
   }:
  
positive.code:     export _REL_PYTHON_MODULE_PATH=$(toPythonPath $out)
    '';
  
    nativeBuildInputs = [ pkg-config cmake doxygen ];
  
    buildInputs =
    [ imagemagick ffmpeg swig python3 jsoncpp
      cppzmq zeromq qtbase qtmultimedia ]
      ++ optional stdenv.isDarwin llvmPackages.openmp
    ;
  
negative.code:   };
  
    patches = [
      # Fix build with GCC 10.
      (fetchpatch {
        name = "fix-build-with-gcc-10.patch";
        url = "https://github.com/OpenShot/libopenshot/commit/13290364e7bea54164ab83d973951f2898ad9e23.diff";
  