Scalable System Design and Architecture Questions

Focuses on designing systems that scale to large numbers of users and high load while balancing consistency, availability, and operational concerns. Candidates should discuss application programming interface design, data flow, load distribution and load balancing, caching strategies, database selection and partitioning, indexing, replication, consistency models, microservices boundaries, synchronous and asynchronous communication patterns, message and event architectures, deployment and rollout strategies, and measures for capacity planning and performance optimization. Answers should include trade off analysis, expected bottlenecks, quantification where possible, and rationale for architecture decisions.