practice a little every day, paws crossed ♡
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 2911–2940 of 4616 results
- OpenAIMediumSoftware EngineerDebug a Machine Learning Pipeline
This question evaluates a candidate's ability to diagnose production machine learning failures, covering competencies in data quality, data and concept drift detection, model versioning and deployment checks, and operational debugging within an MLOps context.
Machine LearningTechnical Screen - OpenAIMediumMachine Learning EngineerDebug a Transformer Implementation and Implement a KV Cache for Decoding
Practice ML coding question on Transformer language models: find and fix several deliberately planted bugs in a decoder-only Transformer implementation, then implement key-value caching from scratch for autoregressive generation. Tests attention mechanics, tensor-shape reasoning, causal masking, position handling, and verification against full recomputation.
Machine LearningTechnical Screen - OpenAIHardSoftware EngineerDebug a failing ML classifier
This question evaluates a candidate's ability to diagnose a poorly generalizing ML classifier, testing practical knowledge of data leakage, feature drift, and model calibration. It assesses applied machine learning debugging skills — including cross-validation design and error analysis — commonly tested in senior engineering and ML roles.
Machine LearningTechnical Screen - OpenAIHardMachine Learning EngineerDebug a transformer training pipeline
An OpenAI ML engineer technical-screen debugging question: given a PyTorch Transformer training pipeline whose loss diverges and validation accuracy stays near chance (plus mask IndexErrors, AMP crashes, and nondeterminism), identify the distinct bugs and fix them. It tests Transformer internals - attention/causal masking, teacher-forcing label shift, positional encodings, ignore_index loss, optimizer and GradScaler order, determinism, and DDP - along with writing unit tests and a structured debugging plan.
Machine LearningTechnical Screen - OpenAIMediumData ScientistDebug and harden trial-assignment Python code
This question evaluates understanding of experiment assignment, data integrity, reliability engineering, concurrency, observability, and privacy in data systems, testing competencies around randomness, idempotency, time semantics, retries, and failure-mode identification.
Data Manipulation (SQL/Python)Technical Screen - OpenAIHardMachine Learning EngineerDebug transformer and train classifier
This question evaluates debugging and practical implementation skills for transformer-based text classification, covering model correctness, training loop integrity, data preprocessing, and evaluation metrics within the Machine Learning / Natural Language Processing domain.
Machine LearningTechnical Screen - OpenAIHardMachine Learning EngineerDerive Backpropagation for Matrix-Product Layers
This question evaluates understanding of backpropagation through linear blocks, matrix calculus, and the computation of gradients with respect to individual weight matrices in a product of trainable matrices, including reasoning about tensor shapes and matrix differentials.
Machine LearningTechnical Screen - OpenAIMediumMachine Learning EngineerDescribe handling pressure and present your work
Describe handling pressure and present your work evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - OpenAIMediumAndroid EngineerDesign Android MVVM API Architecture
Design a robust, scalable Android client architecture using MVVM and Unidirectional Data Flow (UDF) to interact with remote REST and streaming APIs, handling configuration changes, lifecycle events, and coroutine cancellation.
System DesignTechnical ScreenAndroidMVVMKotlin Coroutines - OpenAIMediumSoftware EngineerDesign CI/CD Build Caching
This problem evaluates your ability to design a distributed caching system for CI/CD pipelines, focusing on cache key strategies, invalidation, and storage scalability.
System DesignTechnical ScreenDistributed SystemsCI/CDCaching - OpenAIHardSoftware EngineerDesign Command Dispatch and Telemetry Reconciliation for Unreliable Devices
Design a resilient control plane and telemetry reconciliation system for millions of intermittently connected edge devices, ensuring safe command execution, idempotency, and accurate state tracking despite network unreliability.
System DesignTechnical ScreenDistributed SystemsIoTEdge Computing - OpenAIMediumSoftware EngineerDesign First-Fit and Best-Fit Memory Allocation
Design an in-memory heap allocator supporting first-fit and best-fit allocation, block splitting, adjacent free block coalescing, and safe handle validation to prevent stale or forged free operations.
Software Engineering FundamentalsTechnical ScreenMemory ManagementData StructuresLinked List - OpenAIHardSoftware EngineerDesign GPU credit allocator
A multi-tenant GPU credit allocation system design (OpenAI software-engineer system-design screen): track and deduct GPU credits in real time across many nodes, issue/transfer/spend credits via idempotent APIs, and enforce budgets, hierarchical quotas, rate limits, and fair-share with scheduler integration. Covers prepaid vs postpaid, an immutable double-entry ledger with reservations, overspend prevention, failure recovery, scaling, and observability.
System DesignTechnical Screen - OpenAIMediumAndroid EngineerDesign Mobile Model Usage Quotas
Design an end-to-end quota and rate-limiting system for a mobile AI chat client, focusing on client-side state management, API contract design, and multi-device synchronization.
System DesignTechnical Screensystem-designandroidapi-design - OpenAIHardSoftware EngineerDesign Online Chess Matchmaking
This question tests the ability to design a distributed, low-latency matchmaking system that balances player skill (MMR), wait time, and network latency under high concurrency.
System DesignTechnical ScreenScalabilityConcurrencyDistributed Systems - OpenAIMediumSoftware EngineerDesign Online Chess Matchmaking and Clocks
This question tests your ability to design a real-time game backend, focusing on low-latency state synchronization, fair matchmaking, and reliable clock management in a distributed environment.
System DesignTechnical ScreenReal-timeConcurrencyWebSockets - OpenAIMediumSoftware EngineerDesign Payment Authorization, Capture, and Batch Settlement
Design a resilient payment processing platform supporting two-phase payment operations (authorize and capture), double-entry ledgering, and asynchronous batch settlement with external financial gateways.
System DesignTechnical ScreenPaymentsDistributed SystemsLedger - OpenAIMediumMachine Learning EngineerDesign Real-Time Collaborative Editing
This question tests your ability to design a low-latency, distributed synchronization system that manages concurrent text edits from multiple users while maintaining eventual consistency.
System DesignTechnical ScreenDistributed SystemsCRDTConcurrency - OpenAIHardSoftware EngineerDesign Real-Time Electricity Monitoring and Policy Control
Design a distributed real-time electricity monitoring and policy actuation system that ingests high-throughput telemetry, evaluates dynamic load-shedding policies with hysteresis, and reliably issues auditable commands to edge devices.
System DesignTechnical ScreenStream ProcessingIoTDistributed Systems - OpenAIMediumSoftware EngineerDesign Slack-like messaging platform
This question evaluates a candidate's ability to design scalable, secure, real-time messaging systems, testing competencies in distributed systems, data modeling, API design, storage and sharding strategies, search indexing, and notification delivery.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign Video Generation Orchestration
This system design question tests a candidate's ability to architect asynchronous, distributed job-orchestration pipelines at scale. It evaluates practical knowledge of durable queues, state machines, reliability patterns like the outbox and idempotency, and trade-offs between throughput and latency in GPU-constrained systems.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a CI/CD pipeline with scheduler
An OpenAI software-engineering system design interview question: design a production-grade CI/CD pipeline for a large microservices monorepo, end to end. It spans source-control triggers, build and artifact management, layered testing with flaky-test handling, progressive deployment and rollback, observability, supply-chain security, and — the differentiator — the job scheduler that orchestrates pipeline steps (DAG modeling, concurrency, priorities, retries, caching, rate limiting) plus its data stores, queues, APIs, schemas, multi-tenant fairness, KPIs/SLOs, and failure handling.
System DesignTechnical Screen - OpenAIHardSoftware EngineerDesign a CI/CD system with live log streaming
This question tests the ability to design a distributed job orchestration system that handles task dependencies, secure execution, and low-latency log streaming at scale.
System DesignTechnical ScreenDistributed SystemsCI/CDInfrastructure - OpenAIHardSoftware EngineerDesign a ChatGPT-like web chat UI
This problem evaluates your ability to design a performant, scalable front-end architecture for a real-time conversational AI interface, focusing on state management, streaming data handling, and network resilience.
System DesignTechnical ScreenFrontendArchitectureStreaming - OpenAIHardSoftware EngineerDesign a Cloud DevBox Platform
This question evaluates a candidate's ability to design scalable, secure cloud development platforms, testing competencies in distributed systems architecture, orchestration and scheduling, storage and persistence, multi-tenancy and RBAC, runtime isolation, and operational observability.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Cloud Development Environment
Design a secure, multi-tenant cloud development environment platform that provisions isolated compute instances, supports low-latency interactive editing, and reliably persists workspace state across disconnects.
System DesignTechnical ScreenDistributed SystemsCloud InfrastructureContainers & Virtualization - OpenAIMediumSoftware EngineerDesign a Cloud Development Environment Platform Like an Online IDE
Design a cloud development environment platform, like an online IDE, where developers open a repository in a hosted workspace with a browser editor, a terminal and forwarded ports, then stop and resume it later. It tests sandbox isolation, workspace storage, fast startup, secure connectivity and cost control.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Cloud IDE With SSH Access Where One or More Users Share a Host
A system design question about building a cloud IDE in which developers get SSH access to remote development hosts, and a host can be used by one person or shared by several. It tests host lifecycle management, connection routing through a gateway, workspace persistence, multi-user access control and isolation.
System DesignTechnical Screen - OpenAIMediumSoftware EngineerDesign a Content-Addressed Photo Storage Service
Design a scalable, content-addressed photo storage service with cryptographic verification, resumable chunked uploads, reference-counted deduplication, and protections against unauthorized hash-probing attacks.
System DesignTechnical ScreenObject StorageDeduplicationDistributed Systems - OpenAIMediumSoftware EngineerDesign a Conversational AI Assistant
This question tests the ability to design a low-latency, scalable architecture for an LLM-based conversational assistant capable of handling concurrent user requests and streaming responses.
System DesignTechnical ScreenLLMScalabilityStreaming
OpenAI