There were a total of 6 rounds, I got through to the 5th. 2 rounds were recruiter screening, followed by 1 technical coding round with a Leetcode Medium question described below, then 1 System Scalability (not design) question that was quite hard and specific to database scalability. The interviewers did not seem like they wanted to be there. I always ask at the end of each interview "What is your favourite thing about working at Booking.com" and none of them could give me an answer. One of the interviewers even laughed as if I had made a joke, then paused and clearly realised he couldn't start bad mouthing the company to a potential employee and then effectively dodged the question. I think its a pretty big red flag when none of the interviewers can tell you why they like working there, and try to dodge the question.

This was the first interview. In general it was a relaxed conversation with in depth moments. The main goals was to share information about the applicant, the company and see if there is a possible match. I like the academic nuance but the feedback is taking too long and is not clearly communicated.