System Design Fundamentals

System design interviews are the make-or-break round for senior engineering roles, yet most candidates prepare by memorizing diagrams instead of building real architectures. This path changes that. You will work through five progressively complex challenges — from URL shorteners to notification systems — each requiring you to reason about trade-offs in availability, consistency, latency, and cost. Every challenge uses real AWS services so you understand not just the theory but the operational reality of running distributed systems at scale. By the end, you will have a portfolio of architecture blueprints you actually designed and validated, not just read about.