The first introductory meeting was good. She asked about my experience, company values, motivation to work at Revolut, and a basic technical question: how Java code gets executed. I explained the JVM and bytecode.

At the end of the interview, she gave me advice about the next stage if I progressed. One of her recommendations was: "Do not jump to coding straightaway; ask questions and clarify the task."

I progressed to the next stage and received an email detailing what the interview would cover and what to expect. It emphasized the importance of asking questions and not starting to code immediately, along with writing tests. The email also provided a list of resources to study, which I found to be unhelpful and misleading.

The list contained:

• An advanced Java book that I did not understand how to effectively use for a 45-minute question, given its extensive topics and the short preparation time.
• A section on concurrency, which I spent considerable time studying.
• A page written by one of their SWEs about the coding interview.

In the live coding interview, the interviewer did not have his camera on. He briefly told me about his role and team before starting the coding part. He gave me the question: to write a load balancer that returns a service with specific requirements.

Naturally, I started asking questions to understand the task. The interviewer seemed uninterested and just wanted me to "do what I want." For many questions, he did not answer directly but paused and then said, "As I told you before, you can do it the way you want." This was confusing because the recruiter and the email had told me to ask questions and clarify.

I coded the solution and wrote the unit tests. There was no concurrency part, contrary to what the email had suggested I prepare for.

At the end, the interviewer asked about the time complexity of using a HashSet to store services to check for duplicates, and I explained its constant time. He then asked how HashSets perform equality checks, and I explained the answer but used the word "memory addresses" instead of "buckets" for where objects are stored.

It was then time for my questions. One of the questions I asked was about work-life balance, overtime, and weekend work, and how these situations are handled. He answered that they happen but not usually, and there is no compensation or standard company policy for it; it depends on what the manager agrees to. Such a vague answer further confirmed the burnout and stress associated with the role that people complain about.

I received a rejection a few days later with feedback that I lacked an understanding of the contains method for collections (which I used and coded the solution with but initially forgot its Java name, recalling it from Python's in operator) and a lack of understanding of hashmaps internally, which supposedly prevented me from properly assessing time complexity. I had assessed it correctly but did not use the word "buckets."

From the feedback, I realized that this company and the stress of their work are not worth it. They are not serious about their interviews, and the feedback does not accurately reflect what happened during the interview. It appears they are using a checklist, as others have also stated.

Implement a simple load balancer.

Time complexity of HashSet and how does it work?