Your question is Architecture of a Challenging Project. 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).
Walk me through the architecture of your most challenging project.
Explain the system end to end, including requirements, data flows, model stages, training and serving paths, and the decisions you made. Be prepared to discuss scale, latency, reliability, cost, evaluation, monitoring, feature drift, training-serving skew, and significant tradeoffs. If your project did not use machine learning, describe the most technically challenging production system you built and explain how you would introduce or evaluate ML components.