anchor.diff:      "PredictABEL"
       "prefmod"
       "PrevMap"
  -    "ProbForecastGOP"
       "r4ss"
       "RandomFields"
       "rareNMtests"
  
positive.code:     RNetCDF = [ pkgs.netcdf pkgs.udunits ];
      RODBC = [ pkgs.libiodbc ];
      rpanel = [ pkgs.bwidget ];
      rpg = [ pkgs.postgresql ];
      Rpoppler = [ pkgs.poppler ];
      RPostgreSQL = [ pkgs.postgresql pkgs.postgresql ];
      RProtoBuf = [ pkgs.protobuf ];
      RSclient = [ pkgs.openssl.dev ];
      Rserve = [ pkgs.openssl ];
      Rssa = [ pkgs.fftw.dev ];
      rtiff = [ pkgs.libtiff.dev ];
      runjags = [ pkgs.jags ];
      RVowpalWabbit = [ pkgs.zlib.dev pkgs.boost ];
      rzmq = [ pkgs.zeromq pkgs.pkg-config ];
  
negative.code:     Cardinal = [ pkgs.which ];
      chebpol = [ pkgs.fftw ];
      ChemmineOB = [ pkgs.openbabel pkgs.pkg-config ];
      curl = [ pkgs.curl.dev ];
      data_table = [pkgs.zlib.dev] ++ lib.optional stdenv.isDarwin pkgs.llvmPackages.openmp;
      devEMF = [ pkgs.xorg.libXft.dev pkgs.x11 ];
  