I did one first phone interview which lasted about one hour, I was asked quite high level questions about different topics, and it was good to gain some confidence and get a first impression of the team. The second(and last) interview was in person at the office and I interviewed with several team leads and was asked many different questions(problem solving, efficiency, scalability, algorithms, previous job experience, etc). It was thorough but the interviewers were really friendly. It was challenging but definitely recommend applying if you like working in a startup environment, making and impact and working with talented engineers