High-Level System Design (HLD) for Engineering Leaders
In leadership loops, interviewers are not just checking if you know what a Load Balancer or Redis cache is. They are evaluating your operational maturity: How do squads own these services? What is the blast radius when a network link drops? How do you roll it out with zero customer downtime?
3 Classic System Design Prompts in Leadership Loops
Study the exact requirements, component trade-offs, and failure mode defenses interviewers look for.
Design a Real-Time Team Activity Feed (Jira / Slack style)
Atlassian / Slack / MetaThe Prompt: Design an activity notification and audit stream that broadcasts issue updates, mentions, and pull request events to millions of concurrent active users with sub-second latency.
Interactive Architecture Simulator • Fan-out on Write vs. Read
Standard Squad Member (< 10k followers): “With 4,500 followers, the write amplification is completely negligible for a Redis cluster (~2ms). We fan-out on write into each follower's timeline sorted set so timeline reads are instantaneous O(1) lookups (~2ms).”