I applied online without any referral. After a few weeks, I got an email from the recruiter to talk about my background. Then I had one technical interview online for a coding interview in C++ related to my background. Fortunately, I passed it, and then I was invited to on-site interview. The onsite interview consists of 4 slots where I was interviewed about my research background, coding interview (leetcode), etc. Overall, my experience was positive. Everyone is kind and the office was great.

They have (many) very unprofessional HR. They stood me up multiple times during scheduled interviews for no reason. They were non-responsible and rude. It was the worst experience I have ever had.