practice a little every day, paws crossed ♡
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 3991–4020 of 5874 results
- OpenAIMediumSoftware EngineerDesign 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 - OpenAIHardSoftware EngineerDesign credit balance with vector-clock expirations
This question evaluates understanding of distributed-systems concepts such as vector clocks, partial orders, concurrency control and idempotency, plus practical competencies in data structures and algorithms for efficient per-user state management and correctness under concurrent operations.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign in-memory database API
This question evaluates a candidate's ability to design and reason about in-memory data storage, indexing, query planning, and the underlying data structures and algorithms for insert and query operations.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign power grid device monitoring over an unreliable public internet
Design a monitoring system for power grid field devices that report their status over an unreliable public internet. It tests store-and-forward reporting, idempotent ingestion of late and duplicate data, telling silent devices from failed ones, alerting, and security for critical infrastructure.
System DesignOnsite - OpenAIHardSoftware EngineerDesign the GPU Job Scheduler for a Text-to-Video Generation Service
Design a high-throughput, fault-tolerant GPU job scheduler tailored for large-scale text-to-video generation workloads under sustained compute contention. The problem evaluates distributed resource allocation, multi-node gang scheduling, fairness guarantees, and preemption mechanics.
System DesignTechnical ScreenGPU SchedulingDistributed SystemsResource Management - OpenAIMediumSoftware EngineerDesign webhook, POI, chat, CI/CD, payments
This question evaluates proficiency in distributed system design, covering scalability, availability, durability, data modeling, geospatial indexing, event-driven delivery, API design, fault tolerance, security, and operational monitoring for high-throughput backend services.
System DesignOnsite - OpenAIMediumSoftware EngineerDispatch Parcels to Delivery Drones That May Go Silent Mid-Flight
Build an in-process dispatcher that hands delivery parcels to drones, reclaims a parcel when its drone goes silent, rejects stale reports from a drone that already lost its parcel, and quarantines parcels that fail too many times.
Software Engineering FundamentalsTechnical Screenconcurrencystate-machinereliability - OpenAIHardSoftware EngineerDurable Session Cache: Byte Checkpoints, Segments, Thread Safety
A three-part exercise building a durable in-memory session cache: serialize entries to length-prefixed bytes and checkpoint them to disk, split the checkpoint into size-capped segments that reassemble by concatenation, then discuss making the class thread-safe. Tests byte-level encoding, exact round-tripping, and concurrency reasoning.
Software Engineering FundamentalsTechnical Screenserializationpersistenceconcurrency - OpenAIMediumSoftware EngineerExpiring GPU Credit Ledger with Out-of-Order Events and Point-in-Time Balance
A two-part coding exercise to build a GPU credit ledger with expiring grants, usage deducted earliest-expiration-first, out-of-order events and balance queries at any timestamp, then avoid replaying from time zero on every query. It tests event ordering, heap use, checkpointing and invalidation when late events arrive.
Software Engineering FundamentalsTechnical Screen - OpenAIHardSoftware EngineerExplain JS threading and useState vs useRef
This question evaluates understanding of JavaScript's execution model and concurrency mechanisms (including worker-based threading) along with React state-management semantics, specifically the behavioral differences between useState and useRef.
Software Engineering FundamentalsHR Screen - OpenAIEasySoftware EngineerExplain Why You Want This Company and Infrastructure Role
This question assesses the candidate's ability to connect their personal career trajectory with the specific engineering challenges of scaling large-scale AI infrastructure, testing alignment, motivation, and self-awareness.
Behavioral & LeadershipHR ScreenInfrastructureBehavioralCareer Strategy - OpenAIHardSoftware EngineerExplain Your Engineering Ownership
This question evaluates engineering ownership, technical leadership, end-to-end system responsibility, trade-off reasoning, and incident diagnosis by asking about recent hands-on work, technology choices, an owned system, and a production failure and fix.
Behavioral & LeadershipHR Screen - OpenAIMediumSoftware EngineerExplain Your Technical Focus and Responsible Use of AI
Assesses a candidate's technical ownership, practical experience integrating AI systems or tools, and their ability to navigate reliability, safety, and ethical trade-offs.
Behavioral & LeadershipHR ScreenBehavioralAI SafetyTechnical Ownership - OpenAIHardSoftware EngineerExplain your perspective on AI safety
An OpenAI software engineer onsite behavioral question asking you to define AI safety in practical product terms, triage near-term versus long-term risks, and assess AI's effect on human work, the economy, and society. The answer must then connect those views to concrete engineering practice — threat modeling, guardrails, evals and red-teaming, phased rollout, and incident response. It also tests whether you can balance responsible deployment against shipping speed in both directions.
Behavioral & LeadershipOnsite - OpenAIHardSoftware EngineerFault-Tolerant Task Queue with Retries, a Dead-Letter Queue and Task Dependencies
Implement an in-memory fault-tolerant task queue with enqueue, reserve, complete and fail operations, retries up to a configurable attempt limit, and a dead-letter queue for tasks that keep failing. A second part adds dependencies between tasks, testing state-machine design, efficient readiness tracking and handling of failed dependencies.
Software Engineering FundamentalsTechnical Screen - OpenAIHardSoftware EngineerFault-Tolerant Task Queue with Retry Cooldowns, a Dead-Letter Queue and Dependencies
Implement an in-memory fault-tolerant task queue with enqueue, reserve, fail and a dead-letter queue, where each failed task waits out its own cooldown measured from the failure time and returns in its original enqueue order. A second part adds task dependencies, testing state modeling, efficient scheduling and careful edge-case handling.
Software Engineering FundamentalsTechnical Screen - OpenAIHardSoftware EngineerFault-Tolerant Work Queue with Leases, Fencing Tokens and DAG Task Dependencies
Implement a fault-tolerant work queue in which workers claim tasks under expiring leases, crashed workers' tasks are reassigned, and late reports from stale workers are rejected, then add DAG dependencies with cycle detection. It tests leases, fencing tokens, topological release and delivery semantics.
Software Engineering FundamentalsOnsite - OpenAIHardSoftware EngineerFind a Hidden Number When Each Comparison Answer Arrives One Call Late
Find a hidden integer from 1 to n using a comparison API whose answers arrive one call late: each call submits a new guess but returns the result for the previous one. Build a correct search first, then reduce the worst-case number of calls. It tests binary search under delayed feedback and worst-case analysis.
Software Engineering FundamentalsOnsite - OpenAIHardSoftware EngineerFollow Graph with Cheap Snapshots and Top-K Follow Recommendations
Build a one-directional follow graph that supports cheap snapshots and queries against past snapshots, then recommend the top k accounts a user should follow. It tests versioned data structures, snapshot semantics, two-hop graph traversal, heap-based top-k selection and scaling to highly connected accounts.
Software Engineering FundamentalsOnsite - OpenAIHardSoftware EngineerFollow One-Way Links to the Endpoint Node or the Last Node Before a Loop Closes
Given one-way links in which every node has at most one outgoing link, follow the links from a start node and return the endpoint where the walk stops, or the last node visited before the walk would revisit a node. Tests single-successor graph traversal, visited-node bookkeeping and loop edge cases.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerGPU Credit Ledger with Expiring Grants, Out-of-Order Operations and Fast Balances
Implement a GPU credit ledger with expiring grants, subtractions that spend the soonest-expiring credits first, and balance queries, where operations can arrive out of timestamp order. Then avoid recomputing from time zero on every query. It tests event replay, priority queues and checkpoint invalidation.
Software Engineering FundamentalsOnsite - OpenAIMediumSoftware EngineerGPU Credit Ledger: Spend Earliest-Expiring Credits First, Stop on Overdraft
A coding and design question about an in-memory GPU credit ledger that grants expiring credits, charges usage against the credit that expires soonest, and returns no balance once any charge overdraws the account. It tests data structure choice, expiry and boundary conventions, and optimizing the ledger for a very large number of credit changes.
Software Engineering FundamentalsOnsite - OpenAIMediumSoftware EngineerGame Telemetry Windows: Match Counts, Live Sessions, Late Events
Build an in-memory service that counts per-match actions inside a global 10-minute window, tracks each player's live client sessions from heartbeats and logouts, and stays correct when events arrive late. Tests bounded-memory eviction, amortized analysis, lazy deletion and exact window semantics.
Software Engineering FundamentalsOnsitesliding-windowheapqueue - OpenAIMediumSoftware EngineerGenerate Data Labeling Schedules
This question evaluates combinatorial reasoning and constructive algorithm design for generating constrained assignment schedules, including ensuring each human appears a minimum number of times, preventing duplicate human-task pairs, and managing valid ID ranges.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerHiring manager call: walk through your past work, interests and latest project
A hiring manager asks you to describe what you have built, what you want to work on next, and the project you worked on most recently, then describes their own team. Tests whether you can tell a concise career story, separate your own contribution from the team's, and defend the technical decisions of a recent project in depth.
Behavioral & LeadershipTechnical Screen - OpenAIHardSoftware EngineerHow to answer common recruiter screen questions
How to prepare for an OpenAI software-engineering recruiter / HR phone screen. Covers the full set of common screen questions — self-intro, work-setup and sponsorship logistics, employment history and departure narrative, promotion and leadership-vs-coding deep-dives, an ambiguity STAR story, search-timeline and 'why OpenAI', referral context, and compensation — with model answers, a STAR framework, and the mistakes that sink candidates.
Behavioral & LeadershipHR Screen - OpenAIMediumSoftware EngineerImplement A Contiguous Memory Allocator With Free-Block Coalescing
Design a fixed-size contiguous memory allocator supporting allocation and deallocation with immediate adjacent free-block coalescing.
Coding & AlgorithmsTechnical ScreenData StructuresIntervalsBinary Search - OpenAIEasySoftware EngineerImplement Chat Event Counter
This question evaluates data structures and algorithms competency, focusing on designing efficient in-memory counters and time-windowed event aggregation for (userId, chatId) pairs; it is categorized under Coding & Algorithms and has a practical implementation focus.
Coding & AlgorithmsTechnical Screen - OpenAIHardSoftware EngineerImplement Disease and Friend Snapshot Models
This question evaluates skills in graph-based modeling and temporal state simulation as well as the design and implementation of snapshot-capable directed graph data structures, covering competencies in propagation and state transitions (including immunity, recovery, and death), efficient snapshotting, querying, ranking, and diffing of follow relationships. It is commonly asked to assess algorithmic reasoning, correctness under edge cases, and complexity-aware implementation; the problem belongs to the Coding & Algorithms domain and tests both conceptual understanding of dynamic graph behavior and practical application-level implementation of data structures and immutable snapshots.
Coding & AlgorithmsOnsite - OpenAIMediumSoftware EngineerImplement GPU credit ledger
This question evaluates a candidate's ability to design efficient stateful systems and algorithmic data structures for tracking per-tenant resource balances, including handling idempotency, negative balance policies, concurrency, and persistence.
Coding & AlgorithmsTechnical Screen
OpenAI