I interviewed Booking.com in May 2022. The process starts with resume screening. If your resume seems to be a fit, you would receive an email with an invitation to a HackerRank coding challenge which contains both multi-choice questions and a few (algorithmic) coding problems to solve. If you pass the HackerRank challenge a recruiter conducts a short interview to ask about your motivation, you background, etc. If they find you fit after this interview, you get to the technical rounds. First interview focuses on General Programming, Data Structures, Complexity, Popular Computer Science topics, etc. If you pass this one there is another technical round with the focus on System Design. You will be presented with a feature/component that should be designed and you do the system/architectural design while justifying and communicating your solution with the interviewers. If you pass this round there's a final culture fit interview and that's the whole process. I generally had a very positive experience. Interviewers & recruiter were friendly and very knowledgeable. After each round there was a feedback call where you get to know how you have done in the previous round, which all (expect for one) were very quick. Post interview processes (Handling offer letter, contract, HR & legal stuff, etc) were also taken care of very smoothly.