nixpkgs/pkgs/misc/bleeding-edge-fetch-info/synergy.nix

 args: with args; fetchurl { 
  url = http://mawercer.de/~nix/repos/synergy.tar.gz;
  sha256 = "c86dde2f10e7071d823cff542ea6c98a7e29a45e4909034edbd7605caa775a47";}