anchor.diff:    '';
   
     # Enable output images from the placer.
  -  cmakeFlags = [ "-DUSE_CIMG_LIB=ON" ];
  +  cmakeFlags = [
  +    "-DUSE_SYSTEM_BOOST=ON"
  +    "-DUSE_CIMG_LIB=ON"
  +    "-DOPENROAD_VERSION=${src.rev}"
  +  ];
   
     # Resynthesis needs access to the Yosys binaries.
     qtWrapperArgs = [ "--prefix PATH : ${lib.makeBinPath [ yosys ]}" ];
  
positive.code:   ];
  
    buildInputs = [
      boost172
      cimg
      eigen
      lcov
  
negative.code: 
  mkDerivation rec {
    pname = "openroad";
    version = "unstable-2022-07-19";
  
    src = fetchFromGitHub {
      owner = "The-OpenROAD-Project";
      repo = "OpenROAD";
      rev = "2610b3953ef62651825d89fb96917cf5d20af0f1";
      fetchSubmodules = true;
      sha256 = "sha256-BP0JSnxl1XyqHzDY4eITaGHevqd+rbjWZy/LAfDfELs=";
    };
  
    nativeBuildInputs = [
  