Not long after Beyonce's politically-charged video for "Formation" hit VEVO, the official writing credits were released, revealing that Rae Sremmurd hook-master Swae Lee had contributed to the record. On reassessment, it was clear that Swae's slinky rasp cadence was present throughout the record, but of course, it was impossible to determine exactly what he wrote specifically. According to a new interview with Mike WiLL, who produced the track, and has mentored the Sremms from the beginning, Swae came up with the main concept for the song in one line.

Speaking with the New York Times, WiLL recalled Swae freestyling the main line of the hook on the way to Coachella. “And we’re just coming up—we just freestyle, you know?—and Swae Lee said, ‘O.K., ladies, now let’s get in formation.’ And we put it on the VoiceNote. Swae Lee’s got so many voice notes that he doesn’t even record, but I’m like, ‘Dog, we got to do that “get in formation” shit.’ That could be a hard song for the ladies. Some woman-empowerment shit. Like, ‘Ladies, let’s get in line, let’s not just fall for anything.’ I’m seeing that vision.”

As fate would have it, Swae went into the studio to flesh out the line on a beat, which ended up making its way to Beyonce. “We were just thinking about it being a female anthem,” he said. “Because I knew I just wanted a banger with Beyoncé, like a ‘Single Ladies,’ but I wanted it to be a new kind of chant.”

The beatmaker made it clear that Bey made the track all her own from there. "[She took] one little idea we came up with on the way to Coachella, put it in a pot, stirred it up, and came with this smash. She takes ideas and puts them with her own ideas, and makes this masterpiece. She’s all about collaborating.”

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