Olivia Rodrigo has often spoken of her love for Taylor Swift; she told Zane Lowe she is the "biggest Swiftie in the whole world." Speaking to Rolling Stone
in a video interview, Rodrigo said the yelling in this song's bridge and outro ("I hope you get deja vu!") was inspired by Swift's 2019 Lover
song "Cruel Summer
." She wanted the bridge and outro to be really high energy, "'cause the rest of the song is very serene and eerily calm."
"I love 'Cruel Summer,'" she said. "It's one of my favorite songs ever. I love the yell-y vocals in it, like the harmonized yells that she does. I feel like they're super electric and moving, so I wanted to do something like that."
Because of this, Swift was officially credited as a co-writer of "Déjà Vu." Since Jack Antonoff and St. Vincent co-wrote the song, they got credited, too.