Oscar Holter is a swedish songwriter and record producer based in the United States. He was also a former member of band Necro Facility. He is best known for producing songs with the likes of Tove Lo, Carly Rae Jepsen, DNCE, Hailee Steinfeld, Tori Kelly, Cher Lloyd, Christina Aguilera and Adam Lambert.

Work with Katy Perry

He worked with Katy Perry on the following songs:

Songs from Witness (2017):