The interview process consisted of two phone interviews and then an on-site interview.

The first phone interview was algorithms-based, and the second was coding-based. Both interviews included questions ranging from medium to hard difficulty.

The coding interview was especially stressful as the questions were not trivial (e.g., reverse a list, find duplicates) but were still algorithmically interesting.

The on-site interview was intense. I was driven in a limo to the Palo Alto site. It consisted of breakfast, two interviews, lunch, three more interviews, a founders interview, and then dinner. People usually stay for dinner, but I had another event planned that night, so I skipped it.

All interview questions were tough. For most of them, I had to ask for help or hints to get the answer. I still ended up getting the offer, though :)

Also, this place is like an interview slaughterhouse. When I was there, I estimate they interviewed 20-30 people that day, and it seems like they interview that many people on-site at least three days a week.