With regards to this match's relevancy in this thread: http://zero-k.info/Forum/Thread/24943

This shows just how difficult it can be to keep a Jack from breaking through your defenses, and wiping out your economy. I would've recommended using anything mobile enough to outpace a Jack, which may be more than just some Raiders/Scouts with decent range, or Skirmishers with at least decent speed, as some fast Riots, like Venom, or Assaults, like Ravagers, could've worked out well. Static defenses wouldn't cut it, since not even Stingers are effective against such tanky units like Jacks.