anchor.diff:    packagesToSkipCheck = [
       "Rmpi" # tries to run MPI processes
       "gmatrix" # requires CUDA runtime
  +    "gputools" # requires CUDA runtime
       "sprint" # tries to run MPI processes
       "pbdMPI" # tries to run MPI processes
     ];
  
positive.code:       PKG_LIBS = "-L${pkgs.openblasCompat}/lib -lopenblas";
      });
  
      gputools = old.gputools.overrideDerivation (attrs: {
        patches = [ ./patches/gputools.patch ];
        CUDA_HOME = "${pkgs.cudatoolkit}";
      });
  
      gmatrix = old.gmatrix.overrideDerivation (attrs: {
        patches = [ ./patches/gmatrix.patch ];
        CUDA_LIB_PATH = "${pkgs.cudatoolkit}/lib64";
        R_INC_PATH = "${pkgs.R}/lib/R/include";
        CUDA_INC_PATH = "${pkgs.cudatoolkit}/include";
      });
  
      EMCluster = old.EMCluster.overrideDerivation (attrs: {
        patches = [ ./patches/EMCluster.patch ];
      });
  
negative.code:     RPushbullet = [ pkgs.which ];
      qtpaint = [ pkgs.cmake ];
      qtbase = [ pkgs.cmake pkgs.perl ];
      gmatrix = [ pkgs.cudatoolkit pkgs.which ];
      RCurl = [ pkgs.curl.dev ];
      R2SWF = [ pkgs.pkgconfig ];
      rggobi = [ pkgs.pkgconfig ];
  