anchor.diff:      ninja
     ] ++ lib.optionals cudaSupport [ cudatoolkit_joined ];
   
  -  buildInputs = [ blas blas.provider oneDNN ]
  +  buildInputs = [ blas blas.provider ]
       ++ lib.optionals cudaSupport [ cudnn magma nccl ]
       ++ lib.optionals stdenv.isLinux [ numactl ];
   
  
positive.code:   openMPISupport ? false, openmpi ? null,
    buildDocs ? false,
    cudaArchList ? null,
    numpy, pyyaml, cffi, click, typing, cmake, oneDNN, hypothesis, numactl, psutil,
    linkFarm, symlinkJoin,
  
    # virtual pkg that consistently instantiates blas across nixpkgs
  
negative.code: 
    USE_MKL = blas.implementation == "mkl";
  
    # Unlike MKL, oneDNN (née MKLDNN) is FOSS, so we enable support for
    # it by default. PyTorch currently uses its own vendored version
    # of oneDNN through Intel iDeep.
    USE_MKLDNN = mklDnnSupport;
    USE_MKLDNN_CBLAS = mklDnnSupport;
  
  