anchor.diff:  
   mkDerivation rec {
     pname = "libqtav";
  -  version = "1.12.0";
  +  version = "git-2020-09-10";
   
     nativeBuildInputs = [ extra-cmake-modules qttools ];
     buildInputs = [
       qtbase qtmultimedia qtquick1
       libGL libX11
  -    libass openal ffmpeg_3 libuchardet
  +    libass openal ffmpeg libuchardet
       alsaLib libpulseaudio libva
     ];
   
     src = fetchFromGitHub {
  -    sha256 = "03ii9l38l3fsr27g42fx4151ipzkip2kr4akdr8x28sx5r9rr5m2";
  -    rev = "v${version}";
  +    sha256 = "0qwrk40dihkbwmm7krz6qaqyn9v3qdjnd2k9b4s3a67x4403pib3";
  +    rev = "2a470d2a8d2fe22fae969bee5d594909a07b350a";
       repo = "QtAV";
       owner = "wang-bin";
       fetchSubmodules = true;
  
positive.code: { mkDerivation, lib, fetchFromGitHub, extra-cmake-modules
  , qtbase, qtmultimedia, qtquick1, qttools
  , libGL, libX11
  , libass, openal, ffmpeg_3, libuchardet
  , alsaLib, libpulseaudio, libva
  }:
  
  
negative.code:     homepage = "http://www.qtav.org/";
      maintainers = [ maintainers.jraygauthier ];
      platforms = platforms.linux;
    };
  }
  