Your question is Design a Rate Limiter. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Design a rate limiter to ensure API calls do not exceed a given QPS constraint.
Asked in the Onsite stage, system design and troubleshooting round. Candidate discussed Token Bucket and Sliding Window algorithms. Reported follow-up: How would you ensure consistency in a distributed environment?