Shot in sequence.
Although there was a definitive script, the Duplass brothers encouraged their actors to improvise as much as possible.
It's interesting to read that the executive producers for this small art-house movie, were the brothers Ridley and Tony Scott, who are both known for their big American action blockbusters, everything this small art-house movie isn't about. Ridley and Tony Scott made among others: Alien, Blade Runner, Gladiator, Top Gun and True Romance.
On the theatrical poster, Jonah Hill is the only actor not listed as an Academy Award nominee/winner. Hill would later earn nominations in the Best Supporting Actor category for Moneyball (2011) and The Wolf of Wall Street (2013).