anchor.diff:    date = "2019.0";
     rel = "117";
   
  -  src = fetchurl {
  -    url = "http://registrationcenter-download.intel.com/akdlm/irc_nas/tec/13575/l_mkl_${version}.tgz";
  -    sha256 = "1bf7i54iqlf7x7fn8kqwmi06g30sxr6nq3ac0r871i6g0p3y47sf";
  -  };
  +  src = if stdenvNoCC.isDarwin
  +    then
  +      (fetchurl {
  +        url = "http://registrationcenter-download.intel.com/akdlm/irc_nas/tec/13565/m_mkl_${version}.dmg";
  +        sha256 = "1f1jppac7vqwn00hkws0p4njx38ajh0n25bsjyb5d7jcacwfvm02";
  +      })
  +    else
  +      (fetchurl {
  +        url = "http://registrationcenter-download.intel.com/akdlm/irc_nas/tec/13575/l_mkl_${version}.tgz";
  +        sha256 = "1bf7i54iqlf7x7fn8kqwmi06g30sxr6nq3ac0r871i6g0p3y47sf";
  +      });
   
  -  buildInputs = [ rpm cpio ];
  +  buildInputs = if stdenvNoCC.isDarwin then [ undmg ] else [ rpmextract ];
     propagatedBuildInputs = [ openmp ];
   
  -  buildPhase = ''
  -    rpm2cpio rpm/intel-mkl-common-c-${date}-${rel}-${date}-${rel}.noarch.rpm | cpio -idmv
  -    rpm2cpio rpm/intel-mkl-core-rt-${date}-${rel}-${date}-${rel}.x86_64.rpm | cpio -idmv
  -  '';
  +  buildPhase = if stdenvNoCC.isDarwin then ''
  +      for f in Contents/Resources/pkg/*.tgz; do
  +          tar xzvf $f
  +      done
  +  '' else ''
  +    rpmextract rpm/intel-mkl-common-c-${date}-${rel}-${date}-${rel}.noarch.rpm
  +    rpmextract rpm/intel-mkl-core-rt-${date}-${rel}-${date}-${rel}.x86_64.rpm
  +  '' ;
   
  -  installPhase = ''
  -    mkdir -p $out/lib
  -    cp -r opt/intel/compilers_and_libraries_${version}/linux/mkl/include $out/
  -    cp -r opt/intel/compilers_and_libraries_${version}/linux/mkl/lib/intel64_lin/* $out/lib/
  -    cp license.txt $out/lib/
  +  installPhase = if stdenvNoCC.isDarwin then ''
  +      mkdir -p $out/lib
  +      cp -r compilers_and_libraries_${version}/mac/mkl/include $out/
  +      cp -r compilers_and_libraries_${version}/mac/mkl/lib/* $out/lib/
  +      cp -r compilers_and_libraries_${version}/licensing/mkl/en/license.txt $out/lib/
  +  '' else ''
  +      mkdir -p $out/lib
  +      cp -r opt/intel/compilers_and_libraries_${version}/linux/mkl/include $out/
  +      cp -r opt/intel/compilers_and_libraries_${version}/linux/mkl/lib/intel64_lin/* $out/lib/
  +      cp license.txt $out/lib/
     '';
   
     # Per license agreement, do not modify the binary
  
positive.code:       threading models.
      '';
      homepage = https://software.intel.com/en-us/mkl;
      license = licenses.issl;
      platforms = [ "x86_64-linux" ];
      maintainers = [ maintainers.bhipple ];
    };
  }
  
negative.code: { stdenvNoCC, writeText, fetchurl, rpmextract, openmp, undmg }:
  
  stdenvNoCC.mkDerivation rec {
    name = "mkl-${version}";
  