They are currently still in this round of recruiting, so I have been asked not to share questions, but I can say that the series of four interviews is split up into 3 different types of interview. There are two technical interviews which are fairly similar to other software engineering interviews. The second is with a hiring manager which is technical, but usually there is more of a focus on your design process and specific fields of interest so they can place you on a team if they want to give you an offer. The last is a culture interview, which is more like a typical interview for a non-technical vocation and they basically try to get a sense of whether you are a good fit.