anchor.diff:  
   let
     version = "1.12";
  +
  +  inherit (stdenv.hostPlatform) system;
  +
  +  srcs = {
  +    x86_64-linux = fetchurl {
  +      url = "https://static-meteor.netdna-ssl.com/packages-bootstrap/${version}/meteor-bootstrap-os.linux.x86_64.tar.gz";
  +      sha256 = "0l3zc76djzypvc0dm5ikv5ybb6574qd6kdbbkarzc2dxx64wkyvb";
  +    };
  +    x86_64-darwin = fetchurl {
  +      url = "https://static-meteor.netdna-ssl.com/packages-bootstrap/${version}/meteor-bootstrap-os.osx.x86_64.tar.gz";
  +      sha256 = "01gn3m6qacp3ibvp0rcvm2pq7fi1xds02ws0irypldh7vz3930jl";
  +    };
  +  };
   in
   
   stdenv.mkDerivation {
     inherit version;
     pname = "meteor";
  -  src = fetchurl {
  -    url = "https://static-meteor.netdna-ssl.com/packages-bootstrap/${version}/meteor-bootstrap-os.linux.x86_64.tar.gz";
  -    sha256 = "0l3zc76djzypvc0dm5ikv5ybb6574qd6kdbbkarzc2dxx64wkyvb";
  -  };
  +  src = srcs.${system};
   
     #dontStrip = true;
   
  
positive.code:       chmod +w "\$HOME/.meteor/package-metadata/v2.0.1/packages.data.db"
      fi
  
      $node \''${TOOL_NODE_FLAGS} $out/tools/index.js "\$@"
      EOF
      chmod +x $out/bin/meteor
    '';
  
    meta = with lib; {
      description = "Complete open source platform for building web and mobile apps in pure JavaScript";
      homepage = "http://www.meteor.com";
      license = licenses.mit;
      platforms = [ "x86_64-linux" ];
      maintainers = with maintainers; [ cstrahan ];
    };
  }
  
negative.code:     toolsDir=$(dirname $(find $out/packages -print | grep "meteor-tool/.*/tools/index.js$"))
      ln -s $toolsDir $out/tools
  
      # Meteor needs an initial package-metadata in $HOME/.meteor,
      # otherwise it fails spectacularly.
      mkdir -p $out/bin
  