Very smooth interview process, probably the best one I've had. It took roughly 45 days from sending my CV to receiving the final result, which is not very fast, but it's still reasonable considering I had to fly abroad. There is a phone interview and up to four on-site interviews on one day. All of these were very professional and enjoyable. The difficulty was average, perhaps easier than I expected. You are expected to write code on a whiteboard to solve technical questions, but you can choose any sensible language to do so. Be prepared to answer questions about your past experience and some behavioural questions. You are not expected to be able to solve everything perfectly, but you have to demonstrate the right attitude and show that you know how to approach the presented types of problems. I received the result of the interviews right after the last on-site interview.