anchor.diff:      nat = [ pkgs.which ];
       nat_nblast = [ pkgs.which ];
       nat_templatebrains = [ pkgs.which ];
  -    pbdZMQ = lib.optionals stdenv.isDarwin [ pkgs.binutils.bintools ];
  +    pbdZMQ = lib.optionals stdenv.isDarwin [ pkgs.darwin.binutils ];
       RMark = [ pkgs.which ];
       RPushbullet = [ pkgs.which ];
       qtpaint = [ pkgs.cmake ];
  
positive.code:     pbdZMQ = old.pbdZMQ.overrideDerivation (attrs: {
        postPatch = lib.optionalString stdenv.isDarwin ''
          for file in R/*.{r,r.in}; do
              sed -i 's#system("which \(\w\+\)"[^)]*)#"${pkgs.binutils.bintools}/bin/\1"#g' $file
          done
        '';
      });
  
negative.code:     JuniperKernel = old.JuniperKernel.overrideDerivation (attrs: {
        postPatch = ''
          for file in {R,src}/*.R; do
              sed -i 's#system("which \(otool\|install_name_tool\)"[^)]*)#"${pkgs.darwin.cctools}/bin/\1"#g' $file
          done
        '';
        preConfigure = ''
  