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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 811–840 of 1189 results

  • OpenAIMediumSoftware Engineer
    Design 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 Engineer
    Design 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
  • 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
  • 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
  • OpenAIHardSoftware Engineer
    Design 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 Engineer
    Design 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 Engineer
    Design 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
  • OpenAIEasySoftware Engineer
    Design 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
  • OpenAIHardSoftware Engineer
    Design 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
  • OpenAIHardSoftware Engineer
    Design a team chat system

    This question tests the ability to design a scalable, low-latency, real-time messaging system, focusing on message ordering, delivery guarantees, and high-concurrency state management.

    System DesignTechnical ScreenScalabilityWebSocketsDistributed Systems
  • OpenAIMediumSoftware Engineer
    Design 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
  • OpenAIHardSoftware Engineer
    Design an AI playground editor

    This problem tests your ability to design a scalable, low-latency document editor that integrates real-time AI streaming responses into a persistent, collaborative text environment.

    System DesignTechnical ScreenReal-timeStreamingAPI Design
  • OpenAIMediumSoftware Engineer
    Design an Asynchronous Text-to-Video Generation Service

    This question tests the ability to design a high-latency, asynchronous job-processing pipeline with a focus on fault tolerance, job state management, and reliable resource handling.

    System DesignOnsiteAsync ProcessingScalabilityJob Queues
  • OpenAIMediumSoftware Engineer
    Design an Instagram-like Feed System

    This question assesses the ability to architect a high-scale feed system by balancing pre-computation (push model) versus on-demand computation (pull model) to minimize latency for social media users.

    System DesignTechnical ScreenScalabilityCachingData Modeling
  • OpenAIMediumSoftware Engineer
    Design an Offline Merchant Payment System with Reconciliation

    This question tests your ability to design a distributed payment architecture that supports asynchronous transactions and reliable reconciliation between offline Point-of-Sale (POS) terminals and a centralized ledger.

    System DesignTechnical ScreenDistributed SystemsEventual ConsistencyPayment Gateway
  • OpenAIHardSoftware Engineer
    Design an On-Demand Cloud Notebook Service for ML Engineers

    Design a platform that gives ML engineers on-demand, GPU-backed notebook workspaces they can create, connect to, pause, and resume, covering lifecycle and API design, provisioning latency, persistent storage, and idle-cost control.

    System DesignTechnical Screensystem-designinfrastructurescalability
  • OpenAIHardSoftware Engineer
    Design an Online Chess Platform: Elo Matchmaking, WebSocket Moves, Game Clocks

    Design an online chess platform: match players of similar Elo rating quickly, deliver moves in real time over WebSocket connections, and enforce fair game clocks despite network latency and disconnections. It tests matchmaking, stateful real-time architecture, server-authoritative timing and failover.

    System DesignOnsite
  • OpenAIMediumSoftware Engineer
    Design an Online Chess Service from Launch to Scale

    This problem tests the ability to design a real-time, stateful gaming system, focusing on concurrency control, low-latency communication, and fault tolerance.

    System DesignOnsiteReal-timeConcurrencyWebSockets
  • OpenAIHardSoftware Engineer
    Design an Online Devbox Service for On-Demand Cloud Development Environments

    System design question about an online devbox service that gives engineers cloud development environments they can create, connect to, stop and resume. It tests lifecycle and API design, fast provisioning, persistent workspace storage, connection routing, isolation of user code, idle cost control and failure handling.

    System DesignTechnical Screen
  • OpenAIHardSoftware Engineer
    Design an Online Development Box

    Design an online devbox with authenticated workspace access, isolated code execution, persistent project files, reliable stop/resume, and controlled startup costs.

    System DesignTechnical Screen
  • OpenAIHardSoftware Engineer
    Design an Online Multiplayer Chess Service with Real-Time Moves

    Design an online chess service where two remote players play live games, every move is validated and delivered to the opponent immediately, and results are recorded. It tests authoritative game state, real-time transport, fair clocks, move ordering, recovery of games in progress after failures, and scaling to many concurrent games and spectators.

    System DesignOnsite
  • OpenAIHardSoftware Engineer
    Design an SSH-Based Cloud Development Environment

    This question tests your ability to design a distributed system that manages stateful, long-running compute resources while ensuring isolation, high availability, and secure remote access.

    System DesignOnsiteDistributed SystemsCloud InfrastructureSecurity
  • OpenAIHardSoftware Engineer
    Design an in-memory database

    This problem tests the ability to architect a high-performance, in-memory key-value store, focusing on concurrency control, data structures, and durability guarantees.

    System DesignTechnical ScreenConcurrencyData StructuresCaching
  • OpenAIHardSoftware Engineer
    Design an in-memory key-value database

    Design an in-memory key-value database 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 coffee-shop card payments with tips and nightly batch settlement at scale

    Design a card payment system for coffee shops where purchases are authorized at the counter, tips are added afterwards, and transactions settle in a nightly batch. The discussion centers on scaling nightly settlement, along with idempotent APIs, failure handling and reconciliation against processor reports.

    System DesignOnsite