System Design Interview Questions
Practice 1,105 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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"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."

"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Design a device configuration system
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Model entities for feed content and shares
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Compare core system design tradeoffs with scenarios
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Design a scalable chatbot platform
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Diagnose why a scaled system became slow
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Debug and optimize React performance issues
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Design coding platform leaderboard system
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Compare RDBMS and NoSQL trade-offs
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Design a Random Number Generation API
Design a Random Number Generation API System Design: Random Number Service (REST + Streaming) You are designing a high-scale service that generates ra...
Design a scalable metrics monitoring system
Design a scalable metrics monitoring system Design a Metrics Monitoring System for Large-Scale Services Context You are designing a metrics monitoring...
Design a global multi-game leaderboard
Design a Global, Multi‑Game Leaderboard (Ladder) Service You are designing a global leaderboard platform used by many different games and modes. Each ...
Design distributed log storage service
Design a Distributed Append-Only Log Storage System You are asked to design the storage layer of a distributed, partitioned, replicated append-only lo...
Design viewing history and resume service
Design: Watched-Video and Resume Playback Service Context Design a backend service that records each user’s watched video list and lets them resume an...
Analyze end-to-end request latency
Question Provide a detailed approach to analyze and improve the end-to-end latency of a web request. The request flows from a browser through a CDN, l...