One phone interview then one onsite that lasted about 4-5 hours including a 1 hour technical assessment. Great planning/organization on HR's part and all expenses are paid for the interview process. The technical assessment consisted of some very easy multiple choice questions and a problem that requires coding in Linux. The problem was incredibly confusing at first but is actually quite easy if you take the time to understand what it is asking. Study common coding questions and structs in C. Side note: even if you don't get chosen for a particular role, they can refer you to another department or group that may choose to interview you as well, and it will be a much faster process since your assessment is already on file.

Straight forward - 30 minutes phone screen with behavioral and technical questions on C++. Followed by 5 hour in-person or virtual interview which included both technical and behavioral questions. Each hour was a different interview with different people.