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Problem Understanding
Restate the problem in your own words.
Design a URL Shortener
Design a URL-shortening service that takes a long URL and returns a short alias (6–8 characters) that, when visited, 301/302 redirects to the original. The system is read-heavy by ~10:1, latency-sensitive on the redirect path (it sits on someone else's web page), and globally distributed. The interesting decisions cluster around the id generator, the read-cache strategy, and how to keep click analytics from slowing the redirect down.
- Bit.lyThe canonical URL shortener. Custom aliases for paid users, analytics dashboards, > 600M monthly clicks.
- TinyURLOne of the original shorteners. Anonymous shortening, permanent links, > 25 yrs of operation.
- goo.gl (deprecated)Google's URL shortener — sunset in 2018 but architecturally a clean reference point.
- twitter.com/t.coTwitter's link wrapper — every external link gets shortened to t.co for tracking + click analytics.
Your task: read the problem above, then write what the system is, who uses it, the rough scale, and the headline UX expectation — in your own words. Submit for AI review when you're ready.
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