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Classic question but it opens up fast once you start talking through it.
Start by clarifying the scope and requirements of the parking lot system, such as size, location, and user types. Then, outline a high-level design covering key components like entry/exit, payment, and space allocation, and dive into trade-offs and edge cases. Finally, discuss how you would measure success and iterate based on user feedback.
Pro tip: Anchor your design in a clear user journey and business goal (e.g., maximizing occupancy or reducing wait times), and explicitly tie technical choices back to those outcomes to show product sense.
Ask questions to understand the scope: Is this for a single lot or a network? What types of vehicles? What are the peak hours? What are the key user personas (drivers, attendants, owners)?
Identify main components: parking spots, vehicles, entry/exit gates, payment systems, and user interfaces. Map out the end-to-end user flow from arrival to departure.
Propose a high-level architecture: how spots are allocated (e.g., first-come-first-served, reservation), how payments are processed, and how data is stored and synced across gates.
Discuss trade-offs like cost vs. scalability, real-time vs. batch updates, and handle edge cases such as lost tickets, payment failures, and full capacity.
Propose metrics like average wait time, occupancy rate, and revenue per spot. Suggest how to iterate based on data and user feedback.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.