Short discussion of past related projects and future goals. 3-4 questions solving algorithmic problems on whiteboard about 15-30 minutes per question. Solutions reviewed with interviewer. Experienced candidate vs new graduate treated the same.

Interview consisted of brief background history and remainder was whiteboarding code. No information was provided in advance, no preparation time or access to references, expected algorithms memorized. If its been any time since you studied undergrad CS algos, you will not have a good time.