Designing a URL Shortener

Summary

A classic system design interview question — requiring you to reason about ID generation, redirect performance, database choice, and handling scale, all in a deceptively simple-sounding product.

• 1Design the core flow: generate a short code, store the mapping, redirect on lookup.
• 2Decide how you'd generate unique short codes at scale without collisions.
• 3Consider a caching strategy for the very read-heavy redirect lookup path.