Your question is Async Without Blocking. 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).
How do you handle asynchronous operations in a high-throughput environment without blocking the main event loop?
Explain how nonblocking I/O, worker execution, concurrency limits, and backpressure work together. Distinguish I/O-bound operations from CPU-bound work and describe how you would prevent overload while preserving responsiveness.
Scope: discuss the mechanisms using a mainstream event-loop runtime such as Node.js, without designing a complete production system.