Shape Security Software Engineer interview questions

This was one of the worst experiences I've had with a recruiter. The process took weeks. No one replied to my messages. They rescheduled meetings constantly and then never replied to messages.

On-site interview right after a phone interview with HR. The on-site one was a bit long, about 4-5 hours. First the HR and PM had a casual chat with me introducing some of the company. Then other interviewers give about 3 algorithm problems to solve on white board. Some basic knowledge questions were also asked.