alt Hacker NewsOne of our interviews is a technical design question that asks the candidate to design a web-based system for public libraries. It explicitly tests for how simple they can keep it, starting at "a single small town library" scale and then changing the requirements to "every library in the country". The top ever performance was someone who answered that by estimating that even at max theoretical scale, all you need a medium sized server and Postgres.
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Wait, so you are telling me that not every company builds Spotify on design system interview? Impossible
Most people forget that the early web was built in server closets on-site handling hundreds of requests per second. The business was sold hyperscalers because devs wanted more servers and were tired of arguing WHY they wanted more servers. Then they got sold on Highly Available services because every second you're down is a dollar, or more, lost. Nobody mentioned that the cost of building and maintaining it costs more than the money you'd lose except for the largest of organizations.
Don't even get me started on the resume-driven development that came along with it.
And maybe I'm completely wrong. This is a perspective of one.
I have 100% failed interviews by giving that answer when their definition of scale was 10,000!!!! req/sec. Like sorry dude in 2026 that's not much different than 10 req/sec and my original design would work just fine... But that's what happens when your interviewer is a "senior" 24 year old just reading off the prompt.