Kata library
Explore katas — system design kata practice library
Each system design kata is a safe practice scenario with a clear brief, friendly feedback, and room to experiment. Open one, sketch a system design diagram, and see how the simulator reacts.
Practice-firstImmediate feedbackBeginner friendly
Start where you are
Pick a kata that feels approachable.
Each kata is a low-risk way to practice system design decisions. Open one, explore the components, and see how your design handles the scenario. You can change direction anytime.
Beginner–Intermediate 45–75 min Education Technology saasmessaging
Big news on campus
Serve a sudden surge of reads when thousands of users open the same notification at once.
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Beginner–Intermediate 45–75 min Retail Technology retailpayments
Coffee please
Prevent double-charges and duplicate orders during peak demand and retries.
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Intermediate 60–90 min Consumer Internet saasresilience
Ticket Drop
Keep checkout stable during an on-sale surge when a dependency partially fails.
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