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Technicalstandard
How would you design a URL shortener, at the level a PM needs?
How to approach it
Start with requirements and scale (how many links created versus clicked), because reads far outnumber writes and that shapes the design.
How a strong answer opens
“Before the design, I'd clarify features and scale. Links are created once but clicked many times, so reads far outnumber writes, and that shapes everything.”
Outline of a strong answer
Try answering out loud for a few minutes before you open this.
- Clarify features: custom links, expiry, click analytics
- Estimate scale: links created per day versus clicks per day
- Core flow: create a short code, store the mapping, redirect on click
- Use caching for popular links since reads dominate
- Discuss abuse: spam and phishing links, rate limits
- Name metrics: redirect speed, uptime, abuse rate
Where this question usually goes wrong
Jumping into hashing details without clarifying requirements, scale, or the abuse problem of spam and phishing links.
Learn the method
System design for PMs in Module 6, Technical for PMs.
The full kit has worked answers in full, start to finish, for every round type. $129 once.
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