Pretty easy, just a take home test about data structures and runtimes. They sent an email to me in order to do this, gave me a lot of time to complete it as well.

Initially, they mail the student and ask for the availability. Before the interview, they let you wait in the reception with a guest identification. The interview is around 30 to 40 minutes. They ask about your experiences with self-projects and previous co-ops. They give a tour of their office and explain the work environments after the interview.