Artist: Katy Perry - Producer: Max Martin - Producer: Shellback - Producer: Oscar Holter - Engineer: Sam Holland - Asst. Recording Engineer: Jeremy Lertola - Asst. Recording Engineer: Cory Bice - Editor: Peter Karlsson - Recording Engineer: Daryl "DJ Durel" McPherson - Mixer: Serban Ghenea - Mix Engineer: John Hanes - Keyboards: Oscar Holter - Programmer: Oscar Holter - Keyboards: Shellback - Programmer: Shellback - Background Vocalist: Shellback - Vocals: Katy Perry - Remixer: MUNA