anchor.diff:  { lib
   , rustPlatform
   , python
  -, fetchpatch
   , fetchFromGitHub
   , pipInstallHook
   , maturin
  
positive.code:     pipInstallPhase
    '';
  
    installCheckInputs = [ pytestCheckHook numpy ];
    preCheck = ''
      export TESTDIR=$(mktemp -d)
      cp -r $TMP/$sourceRoot/tests $TESTDIR
      pushd $TESTDIR
    '';
    postCheck = "popd";
  
negative.code: 
  rustPlatform.buildRustPackage rec {
    pname = "retworkx";
    version = "0.6.0";
  
    src = fetchFromGitHub {
      owner = "Qiskit";
      repo = "retworkx";
      rev = version;
      sha256 = "11n30ldg3y3y6qxg3hbj837pnbwjkqw3nxq6frds647mmmprrd20";
    };
  
    cargoSha256 = "1vg4yf0k6yypqf9z46zz818mz7fdrgxj7zl6zjf7pnm2r8mq3qw5";
  
    propagatedBuildInputs = [ python ];
  
    nativeBuildInputs = [ pipInstallHook maturin pip ];
  
    # Needed b/c need to check AFTER python wheel is installed (using Rust Build, not buildPythonPackage)
    doCheck = false;
    doInstallCheck = true;
  
    installCheckInputs = [ pytestCheckHook numpy ];
  
    buildPhase = ''
      runHook preBuild
      maturin build --release --manylinux off --strip
      runHook postBuild
    '';
  
  