My first interview was a one hour skype call with a software engineer on the ML team. We first had a technical research discussion and then a higher level discussion about what the unity ML toolkit will provide for the ML/RL community. Then, a fairly standard 20 minute coding interview through coderpad.
I was invited for an onsite interview the following week. The day consisted of 3 technical machine learning interviews (research discussion or solve a problem), 1 coding interview with an engineer and 1 behavioral interview with a project manager with a one hour break for lunch. Two of the ML interviews were more open-ended technical discussions and one was probing understanding of particular algorithms/methods. Everyone was extremely friendly and patient during the interviews. The HR team was incredibly helpful in organizing everything (flight, hotels etc.).