Was filmed on location in Charleston, South Carolina; it was originally supposed to be filmed in Wilmington, North Carolina.
All the cast are good friends off set and regularly spend time together.
Nicholas Cirillo read for several characters but the show runners didn't feel he was a good match for any of them, so they gave him the role of Barry and the liberty to let him develop the role as he saw fit, including inventing the iconic "Country club" line.
J.D. revealed in an interview that there were clips of the Pogues friend group that were filmed without the actors' knowledge. In order to capture the authenticity of a group of friends beyond the confines of acting, the show-runners would sometimes have the cameras keep rolling between takes. Many of these unscripted interactions of friends just being friends made it into the show.