System Design Mock Interview
Design a News Feed
Work through the five parts of a system design interview one at a time. An AI interviewer asks the questions, then scores your reasoning against an interview rubric.
The interviewer guides you through topics one by one.
The five parts
Each part is a short mock interview. Start anywhere.
1
Problem Exploration / Scoping
Define the core features, boundaries, scale, and non-functional requirements.
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2
High-Level Design
Sketch the services, stores, and asynchronous paths, then justify the boundaries.
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3
End-to-End Design
Trace a representative request through APIs, data, consistency, and failure handling.
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4
Scaling
Find the bottlenecks, partition the workload, and explain the tradeoffs of each scaling move.
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5
Capacity Planning
Turn the assumptions into request rates, storage growth, and an order-of-magnitude deployment plan.
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Your progress
No sessions yet
Finish a part and your best score lands here. Sessions are saved to your account when you are signed in. For the full reference design, read the Design a News Feed solution.
Problem Exploration / Scoping—
High-Level Design—
End-to-End Design—
Scaling—
Capacity Planning—