The final day of Boston Calling followed the same script as Friday and Saturday—let the kids have the afternoon and give the night to an older, more mature crowd.

The Boston-based Pixies closed the night and the festival, but not before the festival’s September lineup was announced—with The Avett Brothers, Alt-J, and The Alabama Shakes set to headline. The dapper dog in the bowling hat will return at the end of September, just in time for the college crowd’s return.

The Pixies, who in the late ’80s and early ’90s influenced the likes of Nirvana and David Bowie, didn’t have much patience for small talk. It’s a wonder how the Black Francis’ voice always seemed to meld with the larger landscape of the group’s sound. Francis did not have a whole lot of range, but he had plenty of rage. On the surface, the Pixies weren’t as excentric as Beck or have the sonic musicianship of My Morning Jacket, but it was the band’s stop and start harmonies that really made the Pixies a treat to watch. Of course, the band played classics “Where Is My Mind?” and “Here Comes Your Mind,” but for most of the set it was content to rage against the skyline.

The day began with short sets from Boston folk group The Ballroom Thieves, pop singer-songwriter Halsey, and ILOVEMAKONNEN of “Tuesday” fame.

Harmonic folk group The Lone Bellow got the afternoon off in earnest, though. The group’s folk anthem “Green Eyes and a Heart of Gold” was the first tune to get the crowd singing and bobbing along. Lucius followed with pulpy, percussion-heavy indie-rock sound.

For a set, the festival shook off its indie-obsessed roots with Alabama bred Jason Isbell. A country artists for lack of a better term, Isbell is more Melencamp than Tim McGraw. His hard-rocking country garnered a small but loyal following at Sunday’s show.

Vance Joy delighted the courtyard crowd with his Australian falsetto and two radio hits, “Georgia” and “Riptide.” Brooklyn rock group TV On the Radio followed, fitting more words into an hour long set than any other group.

Jack Black and Kyle Glass’s acoustic/metal/comedy duo Tenacious D earned the penultimate set of the festival and treated the audience to an hour of acoustic mashing and Black’s engaging and often absurd stage antics. The best part of the duo’s set was its walk out—two scraggily, middle-aged men in tee shirts walking on stage with straight faces to delirious shouts. Their set started off well, with the popular and funny “Tribute.”

Before the Pixies took the stage, the festivalgoers were treated to the schedule for September, a list of acts co-currated by The National’s Aaron Dessnor. The afore-mentioned headliners will be joined by the likes of CHVRCHES, Hozier, Of Monsters and Men, Walk the Moon, MisterWives, Father John Misty, Ben Howard, Nate Ruess, and others. The organizers dedicated this spring’s top spots to ’90s icons Beck and Pixies—as well as popular festival jam bands like My Morning Jacket, TV On the Radio, and Ben Harper. Boston Calling seems to be going in a younger direction this September.

This isn’t that surprising. The fact is that most of Boston’s student population had fled back home before this late May version of the festival. The fall lineup is for the kids and the spring for the grown ups they leave behind.

Going into its fourth year, Boston Calling is beginning to develop an identity. The organizers like indie-rock groups based in Brooklyn. They like euro-pop groups. They’ll take a few rappers and folk singer-songwriters. What’s the common denominator between Marina and the Diamonds, Jason Isbell, and Beck? They’re cool—or at least generally perceived as such. If you told your roommate you’re off to see them in concert, they’d probably be mildly impressed. Boston Calling likes acts you wouldn’t feel guilty publicly listening to on Spotify. If you made a playlist of the spring lineup, you wouldn’t have to fear getting a text from a friend saying, “You’re listening to Maroon 5? And not Songs About Jane?”