anchor.diff: -{ stdenv, fetchFromGitHub, boost, fftw, qt5 }:
  +{ stdenv, fetchFromGitHub, fftw, qt5 }:
   
  -let version = "0.11"; in
  +let version = "2.1"; in
   stdenv.mkDerivation {
     name = "libkeyfinder-${version}";
   
     src = fetchFromGitHub {
  -    sha256 = "0674gykdi1nffvba5rv6fsp0zw02w1gkpn9grh8w983xf13ykbz9";
  +    sha256 = "07kc0cl6kirgmpdgkgmp6r3yvyf7b1w569z01g8rfl1cig80qdc7";
       rev = "v${version}";
       repo = "libKeyFinder";
       owner = "ibsh";
  
positive.code: 
    postInstall = ''
      mkdir -p $out/include/keyfinder
      cp *.h $out/include/keyfinder
    '';
  }
  
negative.code:   };
  
    buildInputs = [ fftw qt5.base ];
  
    postPatch = ''
      substituteInPlace LibKeyFinder.pro \
        --replace "/usr/local" "$out" \
        --replace "-stdlib=libc++" ""
    '';
  
    configurePhase = ''
  