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System Design 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 361–390 of 517 results
- OpenAIHardSoftware EngineerDesign 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 - OpenAIHardSoftware EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 - 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 - 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 - OpendoorMediumBackend EngineerDesign Map-Based Home Search
This problem tests the ability to design a geo-spatial search service capable of handling high-frequency map interactions, filtering, and data consistency at scale.
System DesignTechnical ScreenGeo-spatialCachingScaling - OptiverHardSoftware EngineerDesign a subscription push service
Design a subscription push service 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 - OracleMediumSoftware EngineerDesign a Video Upload Service for 100 GB Files with Chunked, Resumable Uploads
A system design question about building a service that accepts video uploads of up to 100 GB. It covers moving very large files efficiently, splitting them into chunks, resuming interrupted uploads, choosing storage for bytes and metadata, and scaling to many concurrent uploads.
System DesignTechnical Screen - OscarEasySoftware EngineerDesign a Stateful Outreach Campaign Engine
This problem tests the ability to design a resilient, stateful task scheduler capable of handling asynchronous external triggers (responses) and idempotent state transitions.
System DesignTechnical ScreenDistributed SystemsState MachinesScheduling - OtherMediumAnalytics EngineerMaintain Entry Numbers with Incremental Loads and Historical Backfills
Design incremental per-context entry numbering with idempotent state, contiguous-gap backfills, and correct handling of interleaved late events.
System DesignTechnical Screen - Otter.AiMediumData EngineerDefend a Data Pipeline Architecture and Its Trade-offs
Prepare to defend a production data pipeline you genuinely built or changed. The prompt tests how you connect requirements to architecture, compare alternatives, explain replay and backfills, diagnose a hard failure, quantify outcomes, and reflect on ownership and trade-offs.
System DesignTechnical Screen - Otter.AiEasySoftware EngineerExtend a Key-Value Store with Commits and Explicit Rollover Semantics
Design a versioned key-value store supporting staging, atomic commits, point-in-time snapshot reads, and automated rollover compaction.
System DesignTechnical ScreenKey-Value StoreMVCCConcurrency - PalantirHardSoftware EngineerDesign a scalable interview question bank
Design a scalable interview question bank 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 - Palo Alto NetworksMediumSoftware EngineerDesign a thread-safe high-QPS rate limiter
A Palo Alto Networks system-design screen: design and implement a thread-safe, high-QPS rate limiter that enforces per-identity request quotas. The answer covers algorithm choice (token bucket vs. fixed/sliding window), atomic per-key state with locks or CAS, hot-path performance, bounded-memory eviction, distributed scaling (Redis+Lua, token leasing, consistent-hash partitioning), and rejection semantics.
System DesignTechnical Screen - Paramount CommerceHardSoftware EngineerDesign a Go music player with playlists
This question evaluates object-oriented system design, API and data-structure modeling, state and concurrency management, persistence considerations, and algorithmic time/space complexity within a Go-based music player domain.
System DesignTechnical Screen - PatreonEasyData EngineerDesign a Data Processing System for JSON User Records: Batch vs Streaming Input
Design a data processing system for JSON user records that contain names, addresses and payment methods, and explain how the design changes when the upstream source delivers data in batches versus as a continuous stream. It tests pipeline architecture, idempotent loading, ordering and late data, and the handling of sensitive fields.
System DesignTechnical Screen - PerplexityHardSoftware EngineerDesign a personal finance aggregator
This question evaluates skills in large-scale system design including API and third-party integrations, data ingestion and normalization, transactional consistency and idempotency, security and privacy controls, data modeling for multi-currency financial records, and operational concerns like alerts and budgeting.
System DesignTechnical Screen - PerplexityHardSoftware EngineerDiagnose overloaded Kubernetes cluster
This question evaluates competency in diagnosing and mitigating production overloads in Kubernetes-based microservice architectures, emphasizing observability, autoscaling behavior, resource constraints, and incident-response reasoning.
System DesignTechnical Screen - PinterestMediumSoftware EngineerDesign a Distributed Rate Limiter
This problem evaluates your ability to design a distributed rate-limiting service that maintains low latency while enforcing consistent request quotas across multiple global nodes.
System DesignTechnical ScreenDistributed SystemsCachingConcurrency - PinterestHardSoftware EngineerScheduling Four Apps at Once on Kubernetes and a Node-Feedback Scheduler Plugin
A Kubernetes scheduling exercise for a senior infrastructure role: four applications request scheduling at the same time, and the candidate must ask the questions that settle capacity, priority, placement and coordination, then commit to a plan. A second part designs a scheduler plugin that uses signals reported by nodes.
System DesignTechnical Screen - PlaidEasySoftware EngineerDesign a ChatGPT-like conversational assistant
This question evaluates a candidate's ability to design large-scale conversational AI systems, covering competencies in distributed system architecture, real-time streaming, stateful multi-turn session management, safety controls, and integration with external tools.
System DesignTechnical Screen - PlaidEasySoftware EngineerDesign a geo-distributed rate limiter
This question evaluates a candidate's competency in designing geo-distributed, globally consistent rate limiting systems that enforce per-API-key and additional constraints while balancing low-latency request paths and regional failure tolerance.
System DesignTechnical Screen - Point72HardData EngineerDesign Data Quality and Observability Pipeline
This question evaluates proficiency in designing production data orchestration, data quality validation, and observability frameworks for both batch and streaming pipelines, covering dependency management, schema and integrity checks, and operational handling of anomalous records.
System DesignTechnical Screen