Went on-site after a couple phone screens, technical and cultural. On-site interview consisted of coding challenges of easy-medium, followed by system design questions. Overall a negative experience. I had a major thinking error on one of algorithm questions and bombed it - bad luck. They seemed to jump to conclusions on that and politely gave me a rejection right there - only halfway through the 4 hour interview. There was a lot of ego in the room. It wasn't a good fit anyway.