Practice
Whiteboard problems for real system design practice. Read the requirements, draw your architecture, and reason through the math like you would in an interview.
5 problems are open with a free account; the rest are included with membership.
- Easy
- 1
- Medium
- 3
- Hard
- 2
System Design
| Attempted | Practice | ||
|---|---|---|---|
| Design a Rate Limiter Design a distributed rate limiter that limits the number of requests a user can send to an API within a specific time window. | medium | Free → | |
| Design a URL Shortener Design a URL shortening service like bit.ly: turn long URLs into short codes, redirect visitors fast, and survive read-heavy traffic. | easy | Free → | |
| Design a Web Crawler Design a distributed web crawler that discovers and fetches pages at scale without hammering the sites it visits or crawling the same URL twice. | medium | Sign in → | |
| Design a Notification Service Design a service that delivers notifications across push, email and SMS, survives flaky third-party providers, and does not send the same message twice. | medium | Sign in → | |
| Design a News Feed Design the feed for a social network: when someone posts, decide who sees it and when, and make opening the app fast for everyone including people who follow accounts with millions of followers. | hard | Sign in → | |
| Design YouTube Design the upload and playback core of a video platform: multi-gigabyte uploads that survive bad connections, processing into many resolutions, and playback that starts in seconds anywhere in the world without stalling. | hard | Members |