Newton native Alex Karpovsky has come a long way from performing stand-up at Harvard Square’s Comedy Studio. These days, rather than venturing up to the mike himself, he’s impersonating a struggling comedian, starring as down-on-his-luck humorist Paul in the feature film “Folk Hero and Funny Guy.’’ Karpovsky made an appearance at the Somerville Theatre Saturday night to support his latest project, which was screened as part of Independent Film Festival Boston following its debut at the Tribeca Film Festival on April 16. After the showing, Karpovsky — best known as the cynical Ray Ploshansky on HBO’s “Girls,’’ — and director Jeff Grace discussed the road-trip buddy comedy with audience members. The pair provided insight on the film’s Kickstarter origins, improvised lines, and music, much of which was written by Boston musician Adam Ezra (who also largely inspired the “folk hero’’ in the film, a successful musician — and the best friend of Karpovsky’s character — played by Wyatt Russell). “Folk Hero and Funny Guy’’ also features Meredith Hagner, Hannah Simone, Melanie Lynskey, Heather Morris, Michael Ian Black, and David Cross.