System Design Interview Tip #3: Focus on the core design

Interviews are short. There is little time to cover components unrelated to the core design.

Skip common components not unique to the problem. For example, it is not necessary to include a DNS server in the high-level design, nor to discuss the inner workings of a load balancer in the deep dive. Reserve the bandwidth for the core pieces agreed upon during requirement gathering.

Resist the urge to show off our breadth. Don’t get distracted by non-core features. For example, if the only agreed-upon requirement for a dog walking service is to match canines with walkers, don’t discuss payment, analytics, logging, etc, even though they are essential to the service in real life.

Focus on demonstrating our ability to deliver a quality design under tight time constraints. Give the interviewers plenty to brag about on our behalf.

What are your favorite techniques to stay focused?

Published: 2022-04-19