How does the system design interview work at Amazon?

We have an hour-long interview where the candidate is given a high-level problem. We expect candidates to ask questions and refine both functional and non-functional requirements. Since the problem statement is intentionally ambiguous, candidates must make assumptions and explicitly list and agree on them.

Once we're aligned on scope, we ask the candidate to draw a diagram explaining the system's components, starting from a high-level picture and diving into details. We encourage candidates to think aloud so we can evaluate their reasoning process, problem-solving approach, and ability to handle ambiguity. System design interviews showcase a candidate's experience, theoretical knowledge, and technical expertise.

We don't expect candidates to create a perfect design—after all, such systems are built by large teams over years. Instead, we're looking for sound reasoning and a solid approach. Candidates should remember that it's impossible to cover everything in an hour. They are evaluated on their ability to identify appropriate design patterns, demonstrate technical knowledge, and describe a solution that considers key details. A common pitfall is over-engineering a system that doesn't need to handle massive scale, especially when business requirements call for resource efficiency.