The interview process was pretty long: 4 interviews + a homework. First, a classic interview with the recruiter. Then an development exercise to do at home on your free time. They say you don't have to spend a tremendous amount of time on it, but it seems the expectations are pretty high so maybe you should. Then 2 technical interviews (about 1 hour each) with 2 Proton's engineers: the first was a pair programing, the second was a system design interview. Both interviews were pleasant, no tricky questions. Finally a more casual interview (about 45min) with a manager.

Talent Acquisition do not give feedback on their decision. Starts by asking why do you want to work for them. Then go onto sef introduction and basic questions about wor style and salary, etc.