Instacart System Design interview questions center on real-world logistics problems rather than abstract toy exercises. Expect prompts that mirror the product: cart and checkout consistency, inventory sync across retailers, real-time shopper assignment, delivery routing and ETA prediction, and scaling for unpredictable peak demand. Interviewers evaluate how you clarify requirements, estimate scale, choose appropriate data models and storage, design APIs and messaging flows, reason about consistency/latency trade-offs, and address reliability, monitoring, and compliance. Good answers connect technical choices to business impact and operational realities. For effective interview preparation, practice a five-step framework: clarify constraints, sketch end-to-end flow, pick storage and APIs, plan scaling and failure modes, and finish with monitoring and incremental improvements. Time-box 45 minutes for a full design and be ready to deep-dive into one component. Use mock interviews and whiteboarded diagrams focused on Instacart-like scenarios (order management, inventory pipelines, shopper matching, routing). Emphasize trade-offs, graceful degradation, and measurable success criteria so your solutions feel practical and production-ready.