After I submitted resume, one of recruiters contacted me within 24hrs, and quickly set up a phone screen interview with the hiring team. An interviewer asked me some normal questions then brought me for a onsite interview. I met about 5 Sr engrs, almost all questions they asked related to my past GPU experience and they were really serious taking notes. " I cant tell you " was the only answer I got from them when I asked them some reasonable questions. After talking to my internal resource, I got what Apple is doing. Basically, Apple hired huge number of temporary hunting agents to find some experienced people, in my case, experience in GPU. The purpose of doing it is not for hiring, it is for their own knowledge. If you are from Intel, Nvidia or some other cutting-edge GPU companies and interviewed by Apple GPU org, be very careful to answer their questions such as " Can you tell me how do you verify your block ?" " what is the most interesting bug you have closed? " those are reasonable questions, but just make sure don't go too much into your current project(s).