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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 511–540 of 1311 results

  • GoogleMediumSoftware Engineer
    Safe LLM Digests of App Store Reviews for Product Teams

    Design a pipeline that turns a firehose of untrusted app reviews into LLM-written theme digests for internal product teams, with defenses against prompt injection, spam and personal data leakage.

    System DesignOnsitesystem-designllmprompt-injection
  • GoogleMediumSoftware Engineer
    Shared Distributed In-Memory Cache With Rebalancing and Failover

    Staff-level system design question on building a distributed in-memory cache shared by many backend services. It covers the client API, node memory layout and eviction, key placement and rebalancing, replication and failover, freshness against the database, hot keys, miss storms and cold starts.

    System DesignOther
  • GoogleMediumSoftware Engineer
    Technical Deep Dive: Present and Defend the Design of a Service You Own

    Technical deep-dive question from a senior software engineer loop at Google: explain the architecture of a service you own and walk through its technical details. It tests whether a candidate can present purpose, scale and data flow clearly, then defend design choices, failure handling and trade-offs under probing.

    System DesignOther
  • GoogleHardFrontend Engineer
    Visualize More Than One Hundred Million Map Points

    Design a multiresolution map that turns over one hundred million points into cached heat maps and detailed pins without overwhelming the browser.

    System DesignOnsite
  • GrammarlyMediumSoftware Engineer
    Design Disappearing Direct Messages

    Design an ephemeral direct messaging system that reliably deletes messages after viewing across multiple devices, handles offline delivery, and balances user privacy with abuse reporting.

    System DesignTechnical Screensystem-designdistributed-systemsmessaging
  • GrammarlyMediumSoftware Engineer
    Design a Figma-like collaborative editor

    This question evaluates a candidate's ability in designing real-time collaborative systems, covering concurrency control (OT/CRDT trade-offs), low-latency messaging, data modeling, persistence, client-server synchronization, and fault tolerance for unreliable networks.

    System DesignTechnical Screen
  • GrammarlyMediumSoftware Engineer
    Design a Read-Once Chat System

    This question evaluates a candidate's competence in large-scale system design and distributed messaging, including API and data model design, read-once delivery semantics, consistency trade-offs, and operational concerns like scaling, partitioning, and failure handling.

    System DesignOnsite
  • GrammarlyMediumSoftware Engineer
    Design a collaborative spreadsheet

    This question evaluates system design and distributed-systems competencies such as real-time collaboration, concurrent edit conflict resolution, data modeling for workbooks and sheets, session management, persistence and concrete API design.

    System DesignOnsite
  • GrammarlyMediumSoftware Engineer
    Design a restaurant reservation system

    This question assesses the ability to design a distributed reservation system that handles high concurrency, prevents double-booking, and ensures data consistency.

    System DesignTechnical ScreenConcurrencyDatabase ModelingDistributed Systems
  • GustoMediumSoftware Engineer
    Design restaurant shift scheduling

    This problem tests your ability to design a scalable scheduling system, specifically focusing on data modeling for temporal availability, handling conflicting shift assignments, and API design for concurrent updates.

    System DesignTechnical ScreenConcurrencyData ModelingScalability
  • HackerRankMediumSoftware Engineer
    Design a URL Shortener

    This question assesses the ability to design a URL shortening service (like Bitly) focusing on scalability, distributed ID generation, and efficient data retrieval.

    System DesignTechnical ScreenScalabilityDatabaseCaching
  • HadrianHardSoftware Engineer
    Migrate a Continuously Used Database

    This question tests your ability to design a zero-downtime database migration strategy that handles heterogeneous database engines while maintaining strict data consistency across concurrent read and write operations.

    System DesignOnsiteDatabase MigrationCDCConsistency
  • HarveyMediumSoftware Engineer
    Design Cloud File Storage

    This question tests your ability to design a scalable cloud file storage and collaboration platform, focusing on the architectural separation between metadata and blob storage, chunking, deduplication, and granular access control.

    System DesignOnsiteDistributed SystemsObject StorageAccess Control
  • HarveyMediumSoftware Engineer
    Design File Storage with Metadata, Access Control, and Chunked Uploads

    Design drive-style file storage with metadata and blob separation, ACL checks, resumable chunk uploads, atomic publication, and version conflicts.

    System DesignOnsite
  • HarveyMediumFrontend Engineer
    Design a Chat Application with Durable Conversation History

    Design persistent real-time chat with conversation ordering, idempotent sends, paginated history, optimistic state, delivery receipts, and reconnect catch-up.

    System DesignOther
  • HarveyMediumSoftware Engineer
    Design a Cloud File Storage Service

    This question evaluates competency in designing large-scale distributed file storage and collaboration systems, covering storage and metadata modeling, API design, synchronization and consistency models, resumable large-file handling, versioning, access control, scalability, availability, durability, and security.

    System DesignTechnical Screen
  • HarveyMediumSoftware Engineer
    Design a RAG question-answering system

    Design an enterprise-grade Retrieval-Augmented Generation (RAG) system capable of answering complex natural language queries over millions of internal documents with high precision, low latency, and verifiable citations.

    System DesignOnsiteRAGVector DatabaseInformation Retrieval
  • HarveyMediumSoftware Engineer
    Design a Secure PDF Data Room

    Design an enterprise-grade virtual data room (VDR) for secure legal document sharing, focusing on multi-tenant access control, instant permission revocation, dynamic watermarking, and tamper-evident audit logging.

    System DesignOnsitesystem-designsecurityauthorization
  • HarveyHardSoftware Engineer
    Design a production file storage service

    This question evaluates a candidate's competency in distributed systems and storage architecture, covering metadata schema design, concurrency control for atomic per-directory limits and renaming, transaction boundaries and idempotency, storage models for file bytes, large-file handling, consistency and failure modes, scalability and partitioning, observability, lifecycle management, and security. It is in the System Design domain and is commonly asked because it reveals how a candidate reasons about architectural trade-offs and practical implementation concerns; it tests both high-level conceptual design and hands-on practical application.

    System DesignTechnical Screen
  • HarveyMediumBackend Engineer
    Design a secure document vault

    This question evaluates a candidate's competencies in secure backend system design, covering authentication and authorization, metadata and object storage architectures, integrity verification for chunked uploads, scalability, and operational reliability.

    System DesignOnsite
  • HarveyHardSoftware Engineer
    Determine identical files ignoring metadata

    A Harvey AI system design screen on determining whether two files are byte-identical while ignoring metadata, then scaling to deduplication. It covers hashing algorithm choice (SHA-256/BLAKE3 vs MD5/xxHash), multi-stage verification, collision and false-positive mitigation, streaming and parallel hashing, content-defined chunking, and persistent hash-index/service design.

    System DesignTechnical Screen
  • HeadwayMediumSoftware Engineer
    Design a Rental Search and Booking Platform from Startup to Scale

    Design a short-term rental search and booking system, balancing eventual consistency in search discovery with strict consistency during reservations and checkout.

    System DesignTechnical Screensystem-designconcurrencydistributed-systems
  • HeadwayMediumSoftware Engineer
    Design a Shopping Cart Service That Keeps Inventory Consistent Under Concurrency

    Design the backend for an online store's shopping cart, with the focus on inventory consistency: when stock is reserved, how two shoppers racing for the last unit are resolved, and how abandoned holds are released. It tests data modeling, concurrency control, checkout failure handling and contention on popular items.

    System DesignTechnical Screen
  • HeadwayMediumSoftware Engineer
    Handle traffic spikes and estimate server capacity

    This question evaluates a candidate's competency in performance troubleshooting, capacity planning, and scalable system architecture, focusing on diagnosing overload causes and quantifying infrastructure needs.

    System DesignTechnical Screen
  • HebbiaMediumSoftware Engineer
    Design a Multi-Agent Chat Backend

    This question evaluates a candidate's ability to design scalable, reliable backend architectures that integrate LLMs and multi-agent orchestration, covering distributed systems, streaming responses, conversation context management, tool integrations, observability, and secure handling of sensitive financial data.

    System DesignOnsite
  • HexMediumSoftware Engineer
    Design a Notebook App That Synchronizes Notes

    This question tests the ability to design a resilient client-server architecture for a collaborative editing application that must function reliably under network instability.

    System DesignOnsiteOffline-firstSynchronizationConcurrency
  • HexMediumSoftware Engineer
    Design an In-Flight Entertainment Experience for a Small Screen

    This problem tests the ability to design a high-availability, accessible, and modular UI/UX system under significant physical and connectivity constraints.

    System DesignOnsiteUI/UXEmbedded SystemsArchitecture
  • Hot Agent StartupMediumSoftware Engineer
    Design Flight Booking and Voting Systems

    This question evaluates system design competencies including large-scale backend architecture, data modeling and indexing, database internals, concurrency control to prevent overselling, and high-throughput real-time streaming and metrics for live updates.

    System DesignOnsite
  • HubSpotHardSoftware Engineer
    Design a Netflix-like streaming platform

    A HubSpot software-engineer onsite system-design question: design a Netflix-like video streaming platform covering catalog browse by genre and curated rails (Recently Added, Top Ten), search, adaptive-bitrate playback across web, mobile and TV, cross-device resume, and an upload-to-streamable ingest pipeline. It evaluates service decomposition, data models and API contracts, transcoding and CMAF/multi-DRM packaging, CDN and caching strategy, session concurrency and consistency, multi-region failover, observability and A/B testing, graceful degradation, and cost control at millions of concurrent viewers. The worked solution sizes egress and heartbeat load, corrects the common concurrency, resume, and cache-TTL mistakes, and marks the MVP cut line.

    System DesignOnsite
  • HubSpotHardSoftware Engineer
    Design a near-real-time weather API

    A HubSpot onsite system-design question: build a weather data platform that ingests hourly dumps for ~2,000 U.S. locations and serves the current temperature with an at-most-10-minute freshness SLA. It tests ingestion pipelines, idempotent retries and backfill, caching and invalidation, storage modeling, rate-limit handling, scaling, and observability on freshness SLOs.

    System DesignOnsite