Hackerrank test for 90 mins: multiple choice questions, questions for explaining code/concept, and a question for coding up an algorithm.
The algorithm question was rather challenging, this actually might be the hardest part of the whole process, so be prepared to write good code.
If it was successful, a behavioral interview with HR. They also measure your knowledge of HFT, market making, etc.
Then, code pairing with 2 developers, where they ask you to write an algorithm (in my case it was implementing a data structure with a few methods), not hard, but you need to communicate your ideas and edge cases etc clearly. They also care about concurrency and thread safety.
After that, on-site interviews in Amsterdam - this stage lasts about half a day:
- Interview with managers, which consists of a project deep dive, behavioral questions on a deeper level, explaining some technical concepts and business knowledge. If they see that you're knowledgeable, they might test the limits of that knowledge which is a positive indicator.
- Technical interview with developers: project deep dive on a deeper technical level, follow up questions to test your technical knowledge based on what you listed in your CV, and a system design question (architecture, why did you choose this etc.).
- Lunch with a team member to ask questions, have a feeling of the culture, etc.
- Final interview with the recruiter, and tour around the office. This is more of a discussion rather than an interview but be prepared to ask good questions for the position.
People are friendly, office is amazing, and the offer is great. I declined because I had to pursue another similar opportunity but looks like an amazing place to work. Highly recommended for anyone who is interested in working in a challenging environment with smart people.