It consisted of 4 phases: 1. First contact interview: I made an interview with the leader of my team to get to know me and describe the challenge I needed to deliver. It consisted on a 1 week challenge to solve. The challenge was basically to implement a Voice Activity Detector (VAD). 2. Explain your solution to the team you would be working with. You would present your solution and they would ask you some technical questions on and off the topic. 3. Interview with the managers of Sonos 4. Negotiation phase. I did not reach it Personal opinion. The interview was a nice experience but I had to spend 1 week implementing the solution while working full-time. I spent 2 hours a day to implement and document the solution to not receive an offer in the end. Too much work. In my opinion, if a company asks you to make a challenge like this, they should pay you the hours doing the task.