Your question is Design Highly Available AWS Application. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are responsible for an AWS-hosted application that serves customer traffic through a public endpoint and depends on several internal services and managed databases. The current design has occasional outages when one availability zone degrades, and your team also needs to keep the system secure while preserving uptime. You are asked to redesign it so it stays available during component, zone, and partial regional failures.
How would you architect the application for high availability in AWS while keeping security controls explicit at each trust boundary? Walk through the design choices you would make, the failure modes you would expect, and how you would verify the system continues to serve traffic safely when parts of the stack fail.