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Bit.ly URL Shortener

Time Remaining: 30:00Stage: High Level Design
URL shortener system design: client to load balancer to API service, which reads a Redis cache before the URL store and publishes click events to a queue for an analytics worker

Problem Introduction & Defining Requirements

8/10

Clear scope, low-latency target, and read-heavy traffic assumptions.

Core Entities

9/10

Connected users, original URLs, and short codes with the right attributes.

API/Interface Design

8/10

Defined creation and redirect endpoints with sensible response contracts.

Data Flow

8/10

Explained both write and redirect paths through cache and storage.

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Shared whiteboard

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URL shortener system design: client to load balancer to API service, which reads a Redis cache before the URL store and publishes click events to a queue for an analytics worker

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Performance Summary

Requirements

8/10

You clarified scale, latency, and availability before proposing components.

Try next time

Quantify the cache hit-rate assumption before choosing the storage strategy.

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