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Software Engineer 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 1801–1830 of 2810 results

  • OpenAIHardSoftware Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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
  • OpenAIHardSoftware Engineer
    Design a Retrieval-Augmented Generation (RAG) system

    This question tests the ability to design an end-to-end Retrieval-Augmented Generation (RAG) system, focusing on balancing retrieval accuracy, latency, data freshness, and system reliability.

    ML System DesignTechnical ScreenRAGLLMVector Databases
  • OpenAIMediumSoftware Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design a Text-to-Video Generation Service

    This question tests the ability to design a scalable, reliable asynchronous inference pipeline for resource-intensive generative models, focusing on task orchestration, GPU scheduling, and latency management.

    ML System DesignTechnical ScreenML-SystemsDistributed-SystemsGPU-Orchestration
  • OpenAIMediumSoftware Engineer
    Design 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
  • OpenAIMediumSoftware Engineer
    Design a Time-Windowed GPU Credit Ledger

    Design an in-memory credit ledger that manages time-windowed resource grants and consumptions with out-of-order event ingestion, deterministic allocation, and balance reconciliation.

    Software Engineering FundamentalsTechnical ScreenData StructuresSimulationIntervals
  • OpenAIHardSoftware Engineer
    Design 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
  • OpenAIMediumSoftware Engineer
    Design a Video Generation Service with GPU Fleet Management

    Tests the ability to design an end-to-end distributed ML inference system for compute-intensive video generation, focusing on GPU scheduling, job lifecycle management, fault tolerance, and cost efficiency.

    ML System DesignTechnical ScreenGPU SchedulingDistributed SystemsFault Tolerance
  • OpenAIMediumSoftware Engineer
    Design a chatbot (system design)

    This question evaluates system design skills for ML-powered chatbots with a front-end focus, testing understanding of client-side privacy and storage lifetimes, streamed response delivery, stateless relay architectures, authentication boundaries, rate limiting, and failure-mode handling.

    ML System DesignTechnical Screen
  • OpenAIHardSoftware Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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