System Design and Data

System design and data interviews are about constraints: consistency needs, read/write patterns, throughput, latency, failure modes, ownership boundaries, and operational cost. Strong answers explain why a storage or messaging model fits the access pattern instead of listing technologies.

This group covers databases, ORMs, data modeling, and the data side of distributed systems. Connect schema choices to query paths, transaction boundaries, caching, and how services share or isolate state.

Checklist:

• State assumptions about scale, consistency, and failure before choosing tech.
• Explain read/write paths and hot spots in the data model.
• Name trade-offs between normalization, denormalization, and caching.
• Use child domains for storage engines and ORM depth.