The first interview was by phone, where the Manager asked me a few general questions, confirming information on my Resume about the projects I had worked on.
The second interview took place in person with the department lead and COO - questions, while technical in some aspects, were more aimed at best-practices kind of scenarios and asking me to describe some of my solutions to problems. There was no brain-teaser or "edgy" trick questions which was somewhat of a relief.
The third interview was a group interview with certain members of the team - this was actually the most difficult interview by a long shot, surprisingly, and the team pitched questions which really challenged my background knowledge. This was also a sort of character evaluation, to ensure that I was a good fit personality-wise.