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Structured Learning
"Give a person a fish, and you feed them for a day; teach a person to fish, and you feed them for a lifetime." - Lao Tzu, Chinese philosopher
We don't just hand you solutions
we equip you with a conceptual toolkit to solve problems yourselves —-not just the ones we discuss.
Common Patterns, Unlimited Applications
No more reinventing the wheel for each unique challenge. Utilize our comprehensive design templates that act as a powerful foundation for solving a multitude of issues.
Real-World Code Examples
"Talk is cheap, show me the code." - Linus Torvalds, creator of Linux
Don't just read about it; experience it. Our platform offers not just blog-post theories but actual code snippets and examples that you can pull and run on your machine.
Dive into our 'Codelabs' for hands-on understanding
Forget convoluted setups; complex examples comes wrapped in a Docker container that you can easily clone and execute. This bridges the gap between theory and real-world application, making your learning journey as frictionless as possible.
So yeah, it's pretty awesome. But don't just take our word for it. Try a practice problem!
Design YouTube
YouTube is an online video-sharing platform where users can upload, share, and view videos. It supports various types of videos, including TV show clips, music videos, short and documentary films, movie trailers, and other content such as video blogging (vlogging), short original videos, and educational videos.
Design a News Feed
Design the home feed for a social product — a ranked, near-real-time stream of posts from the accounts a user follows. The hard parts are fan-out and ranking, and they are coupled.
Design Uber
Design a ride-hailing service that matches riders with nearby drivers in real-time, handles hundreds of thousands of location updates per second, and manages the full trip lifecycle.
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Rider enters a pickup location and destination. The system returns an estimated fare and ETA before the rider confirms the request.
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After the rider confirms, the system finds nearby available drivers, ranks them, and assigns one through an offer/accept flow.
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Online drivers continuously report GPS coordinates. During an active trip, the rider sees the driver's live position on a map in near real-time.
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The system manages the full lifecycle of a trip through well-defined states, with each transition triggering appropriate side effects (notifications, metering, payment).
Design Instagram
Design a photo-sharing service — upload images, follow accounts, and see a timeline of recent posts. The read path is a News Feed variant; the new problem is the media write path — upload, transcode, durable blob storage, and CDN delivery.
Design Typeahead System
A typeahead system predicts search queries as users type, showing relevant suggestions in real-time. The core challenge: serve suggestions within milliseconds while handling millions of concurrent users.
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Given a prefix (e.g., "har"), return query suggestions that start with that prefix. The system must efficiently search through millions of stored queries.
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When a user selects a suggestion or submits a search, log the event. Aggregate these events to update frequency counts so future rankings reflect current behavior. New trending queries should appear within 24 hours.
Design Rate Limiter
Design a distributed rate limiter to protect API availability and prevent abuse
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The rate limiter must run inline at the API gateway to block excess traffic before it reaches backend services.
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The gateway must call a limiter module and react correctly on allow vs deny, including returning proper HTTP responses to the client.
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The system must determine a stable identity per request (user, API key, tenant, IP) to track usage fairly and prevent abuse.
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The limiter must allow short bursts of requests while enforcing a long-term average rate per identity.
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The limiter must enforce limits correctly across multiple API gateway instances, so traffic cannot bypass limits by hitting different instances.
-
Operators must be able to update rate limit policies safely without redeploying gateways.
Design YouTube
YouTube is an online video-sharing platform where users can upload, share, and view videos. It supports various types of videos, including TV show clips, music videos, short and documentary films, movie trailers, and other content such as video blogging (vlogging), short original videos, and educational videos.
Design a News Feed
Design the home feed for a social product — a ranked, near-real-time stream of posts from the accounts a user follows. The hard parts are fan-out and ranking, and they are coupled.
Design Uber
Design a ride-hailing service that matches riders with nearby drivers in real-time, handles hundreds of thousands of location updates per second, and manages the full trip lifecycle.
-
Rider enters a pickup location and destination. The system returns an estimated fare and ETA before the rider confirms the request.
-
After the rider confirms, the system finds nearby available drivers, ranks them, and assigns one through an offer/accept flow.
-
Online drivers continuously report GPS coordinates. During an active trip, the rider sees the driver's live position on a map in near real-time.
-
The system manages the full lifecycle of a trip through well-defined states, with each transition triggering appropriate side effects (notifications, metering, payment).
Design Instagram
Design a photo-sharing service — upload images, follow accounts, and see a timeline of recent posts. The read path is a News Feed variant; the new problem is the media write path — upload, transcode, durable blob storage, and CDN delivery.
Design Typeahead System
A typeahead system predicts search queries as users type, showing relevant suggestions in real-time. The core challenge: serve suggestions within milliseconds while handling millions of concurrent users.
-
Given a prefix (e.g., "har"), return query suggestions that start with that prefix. The system must efficiently search through millions of stored queries.
-
When a user selects a suggestion or submits a search, log the event. Aggregate these events to update frequency counts so future rankings reflect current behavior. New trending queries should appear within 24 hours.
Design Rate Limiter
Design a distributed rate limiter to protect API availability and prevent abuse
-
The rate limiter must run inline at the API gateway to block excess traffic before it reaches backend services.
-
The gateway must call a limiter module and react correctly on allow vs deny, including returning proper HTTP responses to the client.
-
The system must determine a stable identity per request (user, API key, tenant, IP) to track usage fairly and prevent abuse.
-
The limiter must allow short bursts of requests while enforcing a long-term average rate per identity.
-
The limiter must enforce limits correctly across multiple API gateway instances, so traffic cannot bypass limits by hitting different instances.
-
Operators must be able to update rate limit policies safely without redeploying gateways.