Your question is Describe Implementation Details of a System You Built. 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).
Explain the specific implementation details of a system you have previously built.
Describe the architecture, important data flows, key APIs or types, concurrency model, failure handling, and how you tested and debugged it. Focus on mechanisms and trade-offs rather than only describing the product’s purpose.