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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
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- 546
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- 11
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Showing 2491–2520 of 3640 results
- OneMain FinancialMediumData ScientistPresent Successful Analytics Project: From Problem to Impact
Evaluates end-to-end analytics project storytelling for an onsite panel presentation. Strong answers cover business context, data, methodology, validation, impact, deployment, stakeholder feedback, and lessons learned.
Behavioral & LeadershipOnsite - OpenAIMediumSoftware Engineer0-to-1 Ownership, Critical Feedback Both Ways, Defining Success, and Why OpenAI
A software engineer behavioral round covering a 0-to-1 project you built, a time you received negative feedback, how you deliver critical feedback to others, how you define success for a project or product, and why you want to join OpenAI. It tests ownership, self-awareness, communication and motivation.
Behavioral & LeadershipOnsite - OpenAIHardSoftware EngineerA Project You Decided Not to Ship
This question evaluates your product judgment, objective decision-making, and ability to prioritize organizational resources over personal or team output.
Behavioral & LeadershipOnsiteBehavioralLeadershipProduct Judgment - OpenAIMediumSoftware EngineerAI Safety Views and Leadership-Principle Behavioral Questions
A hiring-manager round asks for your view of AI safety and how it would shape your engineering work, followed by standard behavioral questions in the style of Amazon's leadership principles. It tests genuine motivation, judgment when safety and speed conflict, and structured, evidence-based storytelling.
Behavioral & LeadershipOnsite - OpenAIMediumSoftware EngineerAdd Consecutive-Value Bonuses to Grid Paths
Tests dynamic programming on a 2D grid with extended state tracking to incorporate multi-step path history for score bonuses, path counting, and lexicographical path reconstruction.
Coding & AlgorithmsOnsitedynamic-programminggridpathfinding - OpenAIHardSoftware EngineerAggregate Recent Message Events And Active Chats
Design an in-memory aggregation system that tracks rolling window message counts and distinct active entities across chats with bounded memory and O(1) amortized operations.
Coding & AlgorithmsOnsiteSliding WindowData StreamsDesign - OpenAIMediumSoftware EngineerBehavioral: why OpenAI, AI safety views, 0-to-1 work, feedback, defining success
Behavioral questions reported from OpenAI's software engineering loop: why OpenAI, how you think about AGI and AI safety, a 0-to-1 project, negative feedback you received, and how you defined success for a project. A slide-based project deep dive then probes technical depth under repeated challenge, testing ownership, calibrated judgment and composure.
Behavioral & LeadershipOnsite - OpenAIMediumSoftware EngineerBuild a SaaS API-Credit Ledger With Expiring Grants and Late Events
Implement an API-credit ledger that grants, spends, and reports balances, where each grant expires and spending always draws from the soonest-expiring usable grant first, even when operations arrive out of timestamp order.
Software Engineering FundamentalsOnsitedata-structuresheapevent-ordering - OpenAIMediumSoftware EngineerClarify and Design Social-Graph Milestones
Clarify ambiguous social-graph milestones before designing follow and unfollow operations, consistent snapshots, and user recommendations. The discussion tests directed-edge semantics, snapshot guarantees, recommendation-policy choices, exclusions, deterministic tie rules, scale assumptions, and contract-focused testing.
Software Engineering FundamentalsOnsite - OpenAIHardMachine Learning EngineerCompute Matrix Prefix Products And Gradients
This question evaluates understanding of automatic differentiation for matrix operations, specifically forward and reverse-mode gradients for sequential, associative (but noncommutative) matrix products, together with algorithmic analysis of time and space complexity.
Machine LearningOnsite - OpenAIMediumMachine Learning EngineerCompute entropy and implement 1-NN
This question evaluates numerical stability and streaming computation for entropy estimation from logits, along with efficient vectorized linear-algebra implementation of 1-nearest-neighbor inference and its interpretation as a neural-network forward pass under different distance metrics.
Machine LearningOnsite - OpenAIMediumSoftware EngineerCompute infection spread time
This problem tests your ability to model a spreading process on a 2D grid using a multi-source Breadth-First Search (BFS) to determine the time required for a state to propagate across the entire space.
Coding & AlgorithmsOnsiteBFSGraphsGrid - OpenAIHardSoftware EngineerCount Events in a Trailing 15-Minute Window with a Fixed-Size Ring Buffer
Implement an event counter that returns how many events occurred in the trailing 15 minutes, using a fixed-size ring buffer of per-second buckets so memory stays bounded at any event rate. It tests circular buffers, stale-slot detection, window boundaries, late events and thread safety.
Software Engineering FundamentalsOnsite - OpenAIMediumMachine Learning EngineerDebug Transformer and Add KV Cache
This problem tests your understanding of transformer architecture by requiring you to fix a broken attention mechanism and implement a Key-Value cache to optimize autoregressive inference.
Machine LearningOnsiteTransformersAttentionInference - OpenAIHardMachine Learning EngineerDebug a Small PyTorch Transformer with Four Bugs, Then Add a KV Cache
Debug a small PyTorch transformer language model that hides four bugs, some of which crash and some of which silently ruin training, then add a key-value cache so generation computes only the newest token each step. It tests causal masking, positional encoding, training-loop order and cached decoding.
Machine LearningOnsite - OpenAIHardMachine Learning EngineerDebug a broken Transformer implementation
This question evaluates a candidate's ability to debug and validate a Transformer implementation, focusing on attention masking, parameter initialization, loss alignment, and other implementation-level correctness issues.
Machine LearningOnsite - OpenAIMediumMachine Learning EngineerDefend a Research Direction and Experiment Design
This question evaluates a candidate's ability to synthesize the state of the art in Machine Learning, defend a research direction, and design rigorous experiments, measuring competencies in literature analysis, methodological justification, experimental design, and technical communication.
Machine LearningOnsite - OpenAIMediumMachine Learning EngineerDerive MLE and Bayesian posterior for Bernoulli
This question evaluates parameter estimation and inferential reasoning for Bernoulli/binomial data, including maximum likelihood estimation and its asymptotic variance, Bayesian updating with a Beta prior and the resulting posterior and posterior predictive probability, as well as interval estimation; it is classified in the Statistics & Math domain. It is commonly asked to assess understanding of frequentist versus Bayesian inference, the behavior and reliability of asymptotic approximations and credible intervals, and the practical implications for predictive probability and uncertainty quantification, testing both conceptual understanding and practical application.
Statistics & MathOnsite - OpenAIMediumMachine Learning EngineerDerive Sharded Matrix Multiplication and Backpropagation
Derive forward and backward computation for column-sharded matrix multiplication across multiple devices. Track every local tensor shape, identify the collective needed for replicated input gradients, and propose tests for shard ordering, scaling, and numerical errors.
Machine LearningOnsite - OpenAIMediumSoftware EngineerDesign Bakery Chain Card Payments With Tips and Nightly Settlement
Design the payment system for a bakery chain's counter terminals, where a card is authorized for the purchase, a tip is added afterward, and each location's transactions are captured together in a nightly settlement batch that must scale as the chain grows.
System DesignOnsitesystem-designpaymentsidempotency - OpenAIMediumMachine Learning EngineerDesign Duplicate File Detection
This question tests the ability to design a scalable content-based deduplication system using cryptographic hashing and distributed storage principles to manage large-scale file ingestion.
System DesignOnsiteScalabilityDistributed SystemsHashing - OpenAIMediumSoftware EngineerDesign GPU Scheduling for a Video Generation Platform
This question tests your ability to design a distributed job scheduling system that manages heterogeneous GPU resources for computationally expensive, variable-length video generation tasks.
System DesignOnsiteGPU SchedulingDistributed SystemsLatency - OpenAIHardSoftware EngineerDesign IDE Sandbox and Payments
This question evaluates system design competencies such as distributed systems architecture, scalability, isolation and security, API and state-machine design, storage and synchronization, resiliency, observability, and compliance applied to two domains: a cloud IDE sandbox and a payment processing backend, with domain: System Design.
System DesignOnsite - OpenAIHardMachine Learning EngineerDesign LLM search handling long token inputs
Design an LLM search and RAG system that handles long documents and long user queries. Covers chunking, hierarchical retrieval, query compression, context budgeting, citations, latency, and evaluation.
ML System DesignOnsite - OpenAIHardSoftware EngineerDesign Photo Storage with SHA-256 Content Deduplication and Safe Deletion
Design a photo storage service that deduplicates identical uploads by their SHA-256 content hash. Cover the upload flow with server-side verification, concurrent identical uploads, deletion with reference counting and garbage collection, and the privacy risks of deduplicating across users. It tests content-addressed storage design.
System DesignOnsite - OpenAIHardSoftware EngineerDesign Power-Grid Device Monitoring over Unreliable Networks: Dedup and Late Events
Design a monitoring platform for power-grid devices that report readings and upload logs over unreliable public networks. Ingestion must be idempotent, deduplicate retransmissions, handle out-of-order and late events and accept batched uploads. It tests IoT ingestion, event-time processing and resilience to reconnect storms.
System DesignOnsite - OpenAIMediumSoftware EngineerDesign Slack-like multi-tenant global messaging system
This question tests the ability to design a global, multi-tenant messaging platform that handles high-concurrency real-time delivery, data isolation, and low-latency synchronization across distributed environments.
System DesignOnsiteDistributed SystemsMulti-tenancyReal-time - OpenAIHardSoftware EngineerDesign a CI/CD system with stuck-job handling
This problem tests your ability to design a distributed job scheduling and orchestration system that handles process failures, network partitions, and job timeouts to ensure reliable execution in a high-scale environment.
System DesignOnsiteDistributed SystemsFault ToleranceCI/CD - OpenAIHardSoftware EngineerDesign a Chat Assistant Inference Service: Streaming, Free-Tier Limits, GPU Scheduling
Design the serving system for a chat assistant built on a large language model: stream replies token by token, rate-limit a free tier alongside paid users, schedule requests onto GPUs efficiently, and meet latency targets. It tests streaming protocols, batching, GPU memory limits, rate limiting and overload handling.
System DesignOnsite - OpenAIHardSoftware EngineerDesign a Cloud IDE That Edits and Runs Code in Browser-Accessible Workspaces
Design a cloud IDE in which developers edit and run code and use a terminal in the browser while their files and execution environments live on remote servers. It tests workspace lifecycle and cold starts, isolation of untrusted code, durable file storage, real-time editor and terminal channels, host scheduling, and failure handling at scale.
System DesignOnsite
OneMain Financial
OpenAI