The success of Tyga's "Rack City" has significantly raised the profile of DJ Mustard, one of several guys—including "Up!" producer Iamsu—who seem to have created a contemporary Bay-pop sound derived from the finger-snap funk of tracks like The Pack's "Vans." (I have a theory that DJ Quik's "Can U Werk Wit Dat" is the secret co-forefather of this movement, but that might be wishful thinking.) Meek Mill's DJ Mustard-produced "I'm Rollin" starts with the same sound, but Meek is a bit more gruesome: I walk up in this bitch, fresher than a mu'fucker/ Pocket full of money and my sneakers got blood on em.