Harry Styles wrote the song with:
American producer Jeff Bhasker, whose previous credits include fun.'s "We Are Young
", Kanye West's "All of the Lights
" and Mark Ronson's "Uptown Funk
Frequent Bhasker associate Tyler Johnson, who was also the engineer on the 2012 Bhasker-produced Pink hit "Just Give Me A Reason
". He has also worked on artist projects for the likes of Ed Sheeran, Taylor Swift, Keith Urban.
Another frequent Bhasker associate, Alex Salibian who is part of the Americans production crew. He was producer and co-writer of Young the Giant's third album Home of the Strange
and is also the musical director of Harry Styles's band, starting with his performance on Saturday Night Live
in April 2017.
Sound engineer and bassist Ryan Nasci, who is another member of Harry's band.
One-time pizza shop worker Mitch Rowland, who lives with Ryan Nasci. When the original session musician dropped out, Nasci suggested Rowland to play guitar on the record and he ended up co-writing nine of the album tracks, while continuing to deliver pizzas between their sessions. Speaking in the documentary Harry Styles: Behind the Album
, the One Direction star said:
"The thing with Mitch is that something felt so new to me – he was someone else who had never done it before. He was working in a pizza shop and had never been in a studio. It felt like we had each other to walk out together. He was someone who had no preconceptions about me or who I was or anything and he's a legend."