System Design Interview Questions
Practice 1,047 real System Design interview questions for 2026. Covers open-ended architecture problems from actual interviews with detailed solutions; System Design interview questions you can use for interview preparation at every seniority level, from mid-level backend roles to staff/infra interviews. System design rounds test how you scope problems, choose APIs and data models, size and shard storage, reason about latency, consistency, fault tolerance and operational costs, and trade off complexity vs. reliability. Companies that weight this category heavily include Meta, Google, and OpenAI, with Amazon and Rippling also asking system-style problems on many teams. Expect System Design to appear mid-to-late in an onsite loop as a 45–90 minute conversational whiteboard or collaborative doc exercise; interviewers score structure, technical depth, trade-off thinking, and communication. To prepare, practice a representative set of large-scale patterns, rehearse back-of-envelope scaling math, and run mock design interviews that force you to justify trade-offs under time pressure.

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"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
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Scale the cache to a distributed system
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Improve and measure service performance
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Design quota enforcement for high concurrency
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Design an extensible ticketing system
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Implement a two-user communications handler
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Design an Instagram-like photo-sharing platform
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Design pickup point planning for ride-hailing
Design an algorithm and high-level system for recommending a pickup point in a ride-hailing app. A passenger requests a ride from an approximate city ...
Ensure thread-safe updates to org hierarchy
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Design an online bookstore for browse and purchase
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Optimize machines for distributed merging cost
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Design a meeting scheduler with cancellations
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Describe end-to-end design of past project
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Design a Collaborative Notes Service
Design a collaborative notes service, similar to a lightweight online document editor. Users should be able to create, read, update, delete, and share...
Design VPC, IP plan, management, storage, SSO
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Implement held transfers with accept/cancel
Implement held transfers with accept/cancel Design and implement a two-phase ("pull-style") money-transfer system in which funds are first held on the...
Design user top-10 songs service
Design user top-10 songs service Design a Service to Compute Each User's Top 10 Songs Context You are designing a backend service for a large-scale mu...
Implement paginated, sortable dynamic table component
Implement paginated, sortable dynamic table component React Table Component: Pagination, Sorting, Dynamic Columns Context You are building a reusable ...
Parallelize the lock BFS safely
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Compare cloud compute; design Kubernetes security and CI/CD
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