anchor.diff:  
   stdenv.mkDerivation rec {
     pname = "libpsm2";
  -  version = "11.2.156";
  -  ifs_version = "10_10_2_0_44";
  +  version = "11.2.185";
   
     preConfigure= ''
       export UDEVDIR=$out/etc/udev
  
positive.code:   src = fetchFromGitHub {
      owner = "intel";
      repo = "opa-psm2";
      rev = "IFS_RELEASE_${ifs_version}";
      sha256 = "0ckrfzih1ga9yvximxjdh0z05kn9l858ykqiblv18w6ka3gra1xz";
    };
  
    postInstall = ''
  
negative.code: 
    buildInputs = [ numactl pkgconfig ];
  
    installFlags = [
      "DESTDIR=$(out)"
      "UDEVDIR=/etc/udev"
      "LIBPSM2_COMPAT_CONF_DIR=/etc"
  