The online interview was formed of 10 questions related to the projects I listed on my CV, a few questions about computer architecture (one of them was about caches) and a final question to "add anything I might want". Following that online interview, I got an on-site interview. The process took 2h. The first hour was about C++, I had to make some functions (Fibonacci, bit handling, etc.) a few questions about specifics of the language (pointers, references, instances, constructors, bit operators, virtual functions, etc.) and a couple final questions about programming practices (debugging, memory leak handling, etc.). The second half was about computer architecture, I had to draw a basic CPU pipeline, hazards, forwarding, out of order execution and required structures for all of that. This second half was more interactive since I had a pen and a whiteboard where I drew whatever I was asked for instead of writing code in a notebook. My overall impression was very good, I had fun and the interviewers where nice. Furthermore ARM paid all travel expenses (Flight, hotel and car)