anchor.diff:      # Make a recently added pure virtual function just virtual,
       # to keep compatibility.
       sed -i 's/virtual void endImage() = 0;/virtual void endImage() {}/' src/nvtt/nvtt.h
  +  '' + lib.optionalString stdenv.isAarch64 ''
  +    # remove x86_64-only libraries
  +    sed -i '/bc1enc/d' src/nvtt/tests/CMakeLists.txt
  +    sed -i '/libsquish/d;/CMP_Core/d' extern/CMakeLists.txt
     '';
   
     cmakeFlags = [
  
positive.code: 
  stdenv.mkDerivation rec {
    pname = "nvidia-texture-tools";
    version = "unstable-2019-10-27";
  
    src = fetchFromGitHub {
      owner = "castano";
      repo = "nvidia-texture-tools";
      rev = "a131e4c6b0b7c9c73ccc3c9e6f1c7e165be86bcc";
      sha256 = "1qzyr3ib5dpxyq1y33lq02qv4cww075sm9bm4f651d34q5x38sk3";
    };
  
    patches = [
      (fetchpatch {
        url = "https://github.com/castano/nvidia-texture-tools/commit/6474f2593428d89ec152da2502aa136ababe66ca.patch";
        sha256 = "0akbkvm55hiv58jx71h9hj173rbnqlb5a430y9azjiix7zga42vd";
      })
    ];
  
    nativeBuildInputs = [ cmake ];
  
  
negative.code:     homepage = "https://github.com/castano/nvidia-texture-tools";
      license = licenses.mit;
      platforms = platforms.unix;
      maintainers = with maintainers; [ wegank ];
    };
  }
  