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System Design 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
- Companies
- 11
- Topics
- 8
- Languages
Showing 331–360 of 517 results
- OpenAIMediumSoftware EngineerDesign a Fault-Tolerant Online Chess Service
This problem tests your ability to design a stateful, fault-tolerant system where move ordering, clock synchronization, and session persistence are critical for game integrity.
System DesignTechnical ScreenDistributed SystemsWebSocketsEvent Sourcing - OpenAIHardSoftware EngineerDesign a Fault-Tolerant Video Generation Platform
This question tests the ability to design a distributed, asynchronous system capable of handling long-running, resource-intensive tasks while ensuring idempotency and fault tolerance in the event of partial component failure.
System DesignTechnical ScreenDistributed SystemsFault ToleranceAsynchronous Processing - OpenAIMediumSoftware EngineerDesign a Fleet Metrics Monitoring Platform, Then Go Deep
Sketch an end-to-end metrics pipeline for a large service fleet, then choose one or two components — cardinality control, storage layout, or alert evaluation — and design them in real depth.
System DesignTechnical Screensystem-designobservabilitytime-series - OpenAIHardSoftware EngineerDesign a GPT chat UI with snapshots and sharing
This question evaluates system-design and engineering competencies for building a multi-tenant LLM chat web application, covering real-time token streaming, snapshot/versioned data modeling, full-text and metadata search, API and schema design, role-based sharing, security, and frontend state management.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Hosted Notebook Platform
This question tests the ability to design a scalable, low-latency infrastructure for hosted interactive notebooks, focusing on container orchestration, state persistence, and session management.
System DesignTechnical ScreenDistributed SystemsContainersOrchestration - OpenAIHardSoftware EngineerDesign a Live Speed-Typing Arena With Mistake Lockouts
Design the backend for a multiplayer typing race where wrong keys lock a player out for 1.5 seconds. Covers authoritative match servers, the lockout mechanism, skill-based matchmaking, ratings and leaderboards, and compensating for network latency.
System DesignTechnical Screenreal-timewebsocketsmatchmaking - OpenAIHardSoftware EngineerDesign a Live Trivia Buzzer Arena with Wrong-Answer Lockouts
Design an online trivia game where 2 to 8 players race to buzz in and answer each question correctly, and a wrong answer locks that player out for one second. Tests authoritative server design for real-time input, lockout state, matchmaking, and fairness across differing network latencies.
System DesignTechnical Screensystem-designreal-timematchmaking - OpenAIMediumSoftware EngineerDesign a Multi-Tenant Online IDE
This question assesses the ability to architect a multi-tenant cloud IDE platform, focusing on secure runtime isolation, resource partitioning, and efficient state management for concurrent user environments.
System DesignTechnical ScreenMulti-tenancySandboxingDistributed Systems - OpenAIMediumSoftware EngineerDesign a Payment Processing Service (Merchant to Payment Provider)
This question tests the ability to design a reliable, fault-tolerant distributed system for handling financial transactions, focusing on idempotency, atomicity, and consistent state transitions.
System DesignTechnical ScreenDistributed SystemsAPI DesignFinancial Systems - OpenAIHardSoftware EngineerDesign a Payment Processing System with Exactly-Once Charging
This question tests the ability to design a fault-tolerant payment system that handles distributed transactions, ensures idempotency, and reconciles state with external gateways.
System DesignTechnical ScreenDistributed SystemsIdempotencyTransactions - OpenAIMediumSoftware EngineerDesign a Payment Processor with Holds, Charges, and Network Batches
Design a hold-and-charge payment processor with honest asynchronous results, durable deduplication, incremental network batches, and safe acknowledgment recovery.
System DesignTechnical Screen - OpenAIEasySoftware EngineerDesign a Payment System
This system design question evaluates a candidate's ability to architect a reliable backend payment flow, including idempotent request handling, transactional data modeling, and reconciliation with external processors. It is commonly asked to assess practical distributed systems skills around failure handling, consistency, and scalability under real-world conditions, testing applied architectural reasoning rather than pure theory.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Photo Storage Service That Deduplicates Uploads by SHA-256 Content Hash
A system design question about a photo service that supports upload, download and delete while keeping only one stored copy of any content with the same SHA-256 hash. It tests content-addressed storage, reference tracking, safe deletion under concurrent uploads, and the security risks of deduplicating across users.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Real-Time Multiplayer Typing Race with Matchmaking and Spectators
A system design question: build a real-time multiplayer typing race where players matched by language into races of 2 to 8 type the same text, see each other's progress and errors live, freeze for one second per error, and can be watched by spectators. It tests matchmaking, server-authoritative real-time state, fan-out to spectators and fairness under network latency.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a Real-Time Multiplayer Typing Race with Typo Freezes and Fair Matchmaking
Design a real-time multiplayer typing race for 2 to 8 players in which the first player to type a generated passage wins and every wrong letter freezes that player for one second. The discussion covers the freeze mechanism, matchmaking, ranking players by score, and keeping races fair when players have different network delays.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Real-Time Online Chess Platform
This question tests your ability to design a low-latency, stateful distributed system that handles real-time bidirectional communication and ensures strict move consistency.
System DesignTechnical ScreenWebSocketsConcurrencyReal-time - OpenAIMediumSoftware EngineerDesign a Slack-Like Messaging System
This System Design question evaluates a candidate's ability to architect a scalable, durable real-time messaging system, testing skills in distributed systems, data modeling, API design, persistence versus low-latency delivery, ordering guarantees, missed-message recovery, notifications, and operational scaling.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a Slack-like real-time messaging system
This problem tests your ability to design a distributed, low-latency messaging system that handles concurrent message delivery, persistence, and synchronization across multiple devices.
System DesignTechnical ScreenScalabilityWebSocketsDatabase - OpenAIMediumSoftware EngineerDesign a Tier-Aware AI Video Generation Service
This problem tests your ability to design a distributed, asynchronous task processing system that balances resource fairness, reliability in the face of compute failures, and tiered prioritization.
System DesignTechnical ScreenDistributed SystemsQueuesTask Scheduling - OpenAIHardSoftware EngineerDesign a User-Respecting Smart-Grid Controller
Design a distributed demand-response and curtailment controller for an electrical grid that sheds load during emergencies while strictly respecting user preferences, device criticalities, and fairness constraints.
System DesignTechnical Screensystem-designdistributed-systemsiot - OpenAIHardSoftware EngineerDesign a crossword puzzle solver system
This problem tests the ability to design an efficient search and constraint-solving system for crossword puzzles, requiring optimized data structures for prefix lookups and a backtracking strategy to handle search space pruning.
System DesignTechnical ScreenBacktrackingTrieConstraint Satisfaction - OpenAIMediumSoftware EngineerDesign a distributed crossword fill solver
This problem tests your ability to design a scalable, distributed architecture capable of solving large-scale constraint satisfaction problems (crossword filling) across a vast vocabulary.
System DesignTechnical ScreenDistributed SystemsConstraint SatisfactionBacktracking - OpenAIHardSoftware EngineerDesign a fullstack app with frontend focus
Design a fullstack app with frontend focus evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a metrics monitoring system, going deep on one or two components
A system design question about a metrics monitoring system that collects time series from services and hosts, stores them, serves dashboard queries and raises alerts. After a brief end-to-end sketch, the candidate goes deep on one or two areas, such as time-series storage, label cardinality, downsampling or reliable alert evaluation.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a minimal ChatGPT with presets
This question evaluates a candidate's competency in designing multi-tenant conversational AI services with reusable, versioned presets, covering API design, data modeling, session state and context-window management, scalability, multi-tenant isolation, privacy, and observability.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a multi-device calendar application
This question tests the ability to design a distributed calendar system focusing on synchronization, conflict resolution for overlapping time slots, and efficient storage of recurring events.
System DesignTechnical ScreenDistributed SystemsData ModelingSync - OpenAIHardSoftware EngineerDesign a multi-tenant CI/CD platform
An OpenAI software-engineering system-design screen asking you to design a scalable, multi-tenant CI/CD platform. It spans Git/event intake, YAML workflow parsing into a job DAG, fair scheduling and runner isolation, live log and status streaming, per-tenant quotas and billing, observability, audit logging, disaster recovery, and zero-downtime deploys.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a multi-tenant Slack-like messenger
This question evaluates skills in large-scale distributed systems architecture, real-time messaging and presence, data modeling for multi-tenant platforms, security and compliance features, and operational concerns like observability and cost efficiency.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a payment system with holds and batching
This question tests the ability to design a high-consistency payment processing system that handles asynchronous state transitions, authorization holds, and batch settlement workflows.
System DesignTechnical ScreenPaymentsIdempotencyDistributed Systems - OpenAIHardSoftware EngineerDesign a scalable payment system
Design a scalable payment system evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen
OpenAI