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Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
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- 11
- Topics
- 8
- Languages
Showing 2521–2550 of 3640 results
- OpenAIMediumSoftware EngineerDesign a Digital Game Store and Distribution Platform Like Steam
A system design interview question asking you to design a digital game store and distribution platform like Steam, covering the catalog, purchases, player libraries, and game downloads and updates. It tests content delivery for very large builds, entitlement consistency with payments, and handling traffic spikes during sales and launches.
System DesignOnsite - OpenAIHardSoftware EngineerDesign a Distributed Crossword Solver
This problem tests your ability to design a distributed system capable of solving large-scale constraint satisfaction problems (crossword puzzles) by partitioning search spaces and managing state across workers.
System DesignOnsiteDistributed SystemsBacktrackingConstraint Satisfaction - OpenAIMediumSoftware EngineerDesign a Fair-Queueing Image-Upscaling Service, One GPU per Job
Design the backend for a SaaS image-upscaling API where every job runs on exactly one accelerator and a scheduler must divide a shared fleet across many paying customers, testing job-store design, weighted scheduling by accelerator-time rather than job count, and recovery from worker, accelerator, and scheduler failures.
System DesignOnsitesystem-designschedulingfair-queueing - OpenAIHardSoftware EngineerDesign a High-Throughput Payment Authorization and Settlement System
This problem tests the ability to design a high-throughput, fault-tolerant distributed system that bridges external payment processors with internal ledger state management.
System DesignOnsiteDistributed SystemsConsistencyPayments - OpenAIMediumSoftware EngineerDesign a Highly Available Conversational AI Service
Start with a minimal stateless conversational AI endpoint that streams responses, then evolve it for scale and resilience. Cover safety and authorization, cancellation, admission control, backpressure, dependency failures, regional isolation, durable history, and metrics that separate serving issues from model issues.
System DesignOnsite - OpenAIHardSoftware EngineerDesign a Large-Scale Streaming AI Product Feature
Design an end-to-end streaming architecture for an AI product feature serving millions of concurrent users. The focus is on low-latency token streaming, connection lifecycle management, data persistence, and graceful failure recovery.
System DesignOnsiteStreaming APIsDistributed SystemsLLM Infrastructure - OpenAIMediumSoftware EngineerDesign a Live Elimination Puzzle Arena With Spectators
Design a real-time game in which up to ~150 players per arena solve timed puzzle rounds, the wrong and slowest are knocked out each round, and large audiences watch live standings. Tests partitioning by arena, authoritative timing, mid-round failover, and isolating spectator fan-out from gameplay.
System DesignOnsitesystem-designreal-timewebsockets - OpenAIMediumSoftware EngineerDesign a Live Riddle Showdown With Round Eliminations and Spectators
Design the backend for a live multiplayer riddle showdown where wrong or slow answerers are eliminated each round and large audiences spectate in real time. Tests room sharding, authoritative round settlement, mid-round crash recovery, and isolating spectator traffic from gameplay.
System DesignOnsitesystem-designreal-timesharding - OpenAIMediumSoftware EngineerDesign a Payment Lifecycle from Hold to Charge and Settlement
This problem tests the design of a distributed, idempotent payment processing system that ensures data consistency and financial integrity across asynchronous state transitions.
System DesignOnsiteDistributed SystemsIdempotencyReliability - OpenAIMediumSoftware EngineerDesign a Payment Orchestration System
Design a resilient merchant-side payment orchestration platform that routes transactions across multiple payment service providers (PSPs) while enforcing strict amount invariants, idempotent state transitions, and auditability.
System DesignOnsitePaymentsDistributed SystemsIdempotency - OpenAIHardSoftware EngineerDesign a Payment Processing System
This question tests the ability to design a distributed payment processing system that guarantees atomicity and consistency under high concurrency and partial network failures.
System DesignOnsiteDistributed SystemsConsistencyIdempotency - OpenAIMediumSoftware EngineerDesign a Payment System That Charges Customers Through an External Payment Provider
A system design interview question asking you to design a payment system that charges customers through an external payment provider. It tests exactly-once charging under retries and timeouts, payment state machines, ledger and reconciliation design, webhook handling, and failure recovery.
System DesignOnsite - OpenAIHardSoftware EngineerDesign a Payment System: Holds and Captures, Batch Charges, Reconciliation, Idempotency
Design a payment system that places holds and captures final amounts, submits charges in batches, reconciles internal records against processor settlement reports, and never double-charges when calls are retried. It tests payment state machines, double-entry ledgers, idempotency and reconciliation.
System DesignOnsite - OpenAIMediumMachine Learning EngineerDesign a Real-Time Sensor Intelligence System
This question evaluates proficiency in end-to-end machine learning system design for real-time sensor-driven products, covering sensor choice trade-offs, data collection and labeling pipelines, model selection and real-time inference, and operational constraints such as latency, reliability, privacy, efficiency, and power.
ML System DesignOnsite - OpenAIMediumSoftware EngineerDesign a Real-Time Trivia Battle Royale Platform with Live Spectating
System design question about a real-time trivia battle royale in which dozens to a hundred or more players per room answer timed rounds, the wrong and slowest are eliminated, and spectators watch live leaderboards. It tests sharding by room, authoritative round settlement, fair answer timing, recovery from a server failure mid-round, and spectator isolation.
System DesignOnsite - OpenAIMediumSoftware EngineerDesign a Reliable Payment Processing System
Design a reliable payment-processing service that prevents duplicate charges and preserves an auditable state history through retries and partial failures. Cover idempotency, exact money representation, timeout ambiguity, asynchronous callbacks, reconciliation, state transitions, partitioning, and operational controls.
System DesignOnsite - OpenAIMediumSoftware EngineerDesign a Sora-Style Video Generation Service with Fair Queueing and Cancellation
A system design question about building a Sora-style text-to-video generation service in which every generation task runs on exactly one GPU. It tests task lifecycle and dispatch design, fair sharing of GPU time across many users, and cancellation of queued and running tasks, including whether a direct RPC to the worker is enough.
System DesignOnsite - OpenAIHardSoftware EngineerDesign a Text-to-Video Generation Platform (Sora-style)
This problem evaluates your ability to design a distributed ML infrastructure that handles high-latency, resource-intensive inference jobs while ensuring scalability, reliability, and content safety.
ML System DesignOnsiteDistributed SystemsML InfrastructureTask Queues - OpenAIHardSoftware EngineerDesign a Text-to-Video Generation System
This question evaluates a candidate's competency in designing scalable ML inference platforms, including GPU resource management and scheduling, asynchronous job orchestration and state-machine-driven job lifecycles, failure classification and recovery, artifact storage, rate limiting, and monitoring for quality and latency.
ML System DesignOnsite - OpenAIMediumSoftware EngineerDesign a URL Shortener
This question tests your ability to design a highly scalable, distributed URL shortening service, focusing on database schema design, request routing, and efficient short-code generation.
System DesignOnsiteScalabilityCachingDatabase Sharding - OpenAIHardSoftware EngineerDesign a URL shortening service
This problem tests your ability to design a distributed, high-scale URL shortening service, focusing on data modeling, collision-resistant ID generation, and performance optimization via caching.
System DesignOnsiteDistributed SystemsDatabase ShardingCaching - OpenAIHardMachine Learning EngineerDesign a chatbot fallback for unknown questions
This question evaluates a candidate's competency in ML system design, focusing on handling model uncertainty, retrieval-augmented components, tool integration, decision policies, and operational evaluation within the ML System Design domain.
ML System DesignOnsite - OpenAIHardMachine Learning EngineerDesign a harmful video content moderation system
This question evaluates a candidate's competency in designing scalable, multi-modal machine learning systems for content moderation, covering architecture, model strategy, labeling and human-in-the-loop workflows, metrics, auditability, and defenses against adversarial evasion.
ML System DesignOnsite - OpenAIMediumSoftware EngineerDesign a parser for a hypothetical language
This question evaluates competency in compiler and language design, covering grammar analysis, parsing algorithms (LL/LR/GLR/Earley/PEG), lexer and parser implementation, AST construction, error reporting and recovery, operator precedence and associativity, and analysis of time/space trade-offs.
Coding & AlgorithmsOnsite - OpenAIHardMachine Learning EngineerDesign a recommendation system end-to-end
This question evaluates a candidate's competency in large-scale machine learning system design, including architecture for candidate generation and ranking, feature engineering across real-time and batch pipelines, training and serving workflows, and monitoring for fairness and safety.
ML System DesignOnsite - OpenAIHardMachine Learning EngineerDesign a regional surge pricing strategy
This question evaluates skills in designing real-time surge pricing systems, assessing competencies in machine learning modeling, control and pricing logic, data engineering, operational robustness, explainability, and monitoring within the System Design domain.
System DesignOnsite - OpenAIEasySoftware EngineerDesign a sandboxed cloud IDE
This question evaluates a candidate's competency in designing multi-tenant distributed systems with strong isolation and sandboxing, runtime lifecycle management, real-time output/log streaming, data persistence, autoscaling, and observability.
System DesignOnsite - OpenAIHardMachine Learning EngineerDesign a search query autocomplete system
This question evaluates a candidate's ability to design a real-time, low-latency search autocomplete system, exercising competencies in architecture, indexing and serving, ranking and personalization, typo-tolerance, multilingual support, abuse prevention and privacy-aware data handling; it is categorized under System Design and emphasizes practical application with architectural-level conceptual reasoning. It is commonly asked to assess how candidates balance stringent latency and scalability requirements with personalization and trending signals, robustness to input errors and multiple languages, and metrics-driven trade-offs across caching, ranking and monitoring.
System DesignOnsite - OpenAIMediumSoftware EngineerDesign a text-to-video GPU job scheduler with one GPU per task and fair queueing
Design a GPU job scheduler for a text-to-video generation service where each task runs on a single GPU and users share capacity through fair queueing. It tests job store design, fairness by GPU time rather than task count, leases and retries, and failure handling across workers, GPUs and the scheduler.
System DesignOnsite - OpenAIHardMachine Learning EngineerDesign an AWS fine-tuning platform for LLMs
This question evaluates a candidate's competency in designing cloud-native ML platforms for fine-tuning large language models, covering distributed training, multi-tenant security and isolation, cost controls, reproducibility, observability, checkpointing, and deployment workflows.
ML System DesignOnsite
OpenAI