The hiring process takes place in several stages. The first is a basic phone interview that takes about a half hour. If that goes well, then you take a skills assessment. If you score well on that, then they fly you out to Wisconsin for the final interview.
The final interview takes place over the course of a day. You'll meet a variety of Epic employees, get a tour of the campus, and sit down for two real interviews. One is a case study with someone in your desired position, and the other is a typical interview with HR.