The Indie Nation Sea: The scene at Chicago's Union Park for the 2012 Pitchfork Music Festival. (Photo: Rebecca Smeyne)

Held in Chicago's Union Park for the seventh straight year, the 2012 Pitchfork Music Festival featured an eclectic mix of indie rock mainstays, rising rap stars and boundary-pushing electronic artists. Back in the VIP area, writers, crew members, artists and their flaks intermingled in the shade while swilling free cups of Heineken, the only beer available at the fest.

A$AP Rocky (second from left) and a portion of the A$AP Mob crew. (Photo: Rebecca Smeyne)

The star of the opening day of the festival (Friday, July 13) was A$AP Rocky, the Harlem hip-hop phenom who brought his entire A$AP Mob crew onstage for the occasion. An hour after his set had wrapped, A$AP and roughly 15 friends were sitting in a dark room in the field house of Union Park, fielding questions from writers during interviews that were scheduled to last exactly five minutes. Outside of the field house, Rocky's manager, Chace Infinite, took a break from shepherding reporters in and outside to embrace Danny Brown, the Detroit rapper who performed at the fest on Saturday night.

The Good Hands People: Sleigh Bells Alexis Krauss crowd surfing. (Photo: Rebecca Smeyne)

While some reps -- like Press Here Publicity's Jen Appel, on site for Sleigh Bells -- got to enjoy parts of the festival after their sole client playing the fest had finished, others, like Motormouth Media's Judy Miller Silverman and David Marek, stayed busy overseeing artists like Flying Lotus, Lower Dens, the Dirty Projectors, Clams Casino, Atlas Sound and Oneohtrix Point Never. The latter artist, an ambient/experimental electronic artist whose 2011 disc "Replica" was widely acclaimed, chatted with Silverman and Marek on Sunday about the new music he was to premiere during his set, as well as his excitement for leaving the festival and watching the season premiere of "Breaking Bad" that night.

The Whole World's a Stage (from left): Cater Adams, Windish Agency; Judy Miller Silverman, Motormouth Media; XL Records' Imran Ahmed; Azizi Gibson of preHISTORIC (signed to Flying Lotus' Brainfeeder label); Pitchfork founder/CEO Ryan Schreiber; Warp Records' Charles Damga; Grimes' back up dancers (Photo: Rebecca Smeyne)

Artists like indie-poppers Cults stayed cool after their set on Saturday and members of the Dirty Projectors chatted with Feist before their respective sets on Friday. Meanwhile, media members like the New York Times' Jon Caramanica, eMusic editor-in-chief J. Edward Keyes and Pitchfork editor Jayson Greene documented the hipster-approved action. Other Pitchfork staffers, like senior editor Ryan Dombal, president Chris Kaskie and founder/CEO Ryan Schreiber, were on hand to cover the fest and make sure all systems were running smoothly.

The Dirty Projectors post Feist-chat. (Photo: Rebecca Smeyne)

But the biggest buzz of the weekend was generated when a certain global pop superstar was spotted watching a Compton rapper without a proper debut album tear through a spirited set on the Blue Stage on Sunday. As Kendrick Lamar spat rhymes from "The Recipe" and prodded the crowd into singing along to his hooks, Lady Gaga, sporting huge sunglasses and a simple dark garment, twirled around and nodded approvingly. Pitchfork Fest had officially been invaded by the mainstream.

Lady Gaga (center, in sunglasses) watchest Kendrick Lamar (right) at the 2012 Pitchfork Festival (Photo by Roger Kisby/Getty Images)

Feist breaking down post-Dirty Projectors chat. (Photo: Rebecca Smeyne)

A$AP Rocky crowd surfing. (Photo: Rebecca Smeyne).

Detroit's Danny Brown who performed at the fest on Saturday night. (Photo: Rebecca Smeyne)

Feeding brains: Flying Lotus dropping science on Saturday. (Photo: Rebecca Smeyne)