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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 1141–1170 of 1311 results
- SnapchatMediumSoftware EngineerDesign a device owner lookup service
This question tests the ability to design a distributed system for tracking the mapping between ephemeral devices and their currently signed-in users, focusing on handling event concurrency and high-throughput read/write operations.
System DesignOnsiteDistributed SystemsConcurrencyCaching - SnapchatMediumSoftware EngineerDesign a metrics collection and alerting system
This question evaluates system design competencies such as scalable time-series data modeling, ingestion and storage architecture, query latency versus retention trade-offs, and alert evaluation logic within the System Design domain.
System DesignOnsite - SnapchatMediumMachine Learning EngineerDesign a search-to-ads ranking pipeline
This question tests the ability to design a high-throughput, low-latency ranking system that balances user experience with monetization goals through multi-stage retrieval and bidding mechanics.
System DesignOnsiteRankingRecommendation-SystemsAd-Tech - SnapchatHardSoftware EngineerDesign a streaming ads system
This question evaluates a candidate's competency in designing low-latency, scalable, and privacy-compliant ad-insertion platforms, encompassing distributed systems, real-time bidding integration, ad format and measurement standards, content and identity signal processing, pacing/frequency control, and multi-region fault tolerance.
System DesignOnsite - SnapchatMediumSoftware EngineerDesign a swipeable video feed backend
This question evaluates system-design competence for building scalable, low-latency backend services that handle feed vending, pagination, personalized ranking, caching, storage, and content eligibility; it is categorized under System Design and tests practical application of distributed systems and backend data engineering principles.
System DesignOnsite - SnapchatHardSoftware EngineerDesign product co-occurrence analytics API
This question evaluates design skills for RESTful APIs and backend systems, covering API schema and versioning, authentication and rate limiting, caching and cache invalidation, storage models, precomputation pipelines, consistency and staleness bounds, monitoring, and operational concerns.
System DesignOnsite - SnapchatMediumSoftware EngineerDesign real-time ad impression and spend tracking
This question tests the ability to design a high-throughput, fault-tolerant system capable of tracking massive volumes of ad impression events and calculating real-time budget spending.
System DesignOnsiteDistributed SystemsCachingHigh Throughput - SnapchatHardSoftware EngineerDesign ride-hailing and price alert systems
This question evaluates a candidate's competency in large-scale system design, including distributed architecture, real-time data processing, geo-spatial indexing and low-latency matching for ride-hailing, plus scalable ingestion, time-series storage, rule evaluation, and reliable notification pipelines for price-tracking, within the System Design domain. It is commonly asked to assess architectural trade-offs around scalability, consistency, availability, fault tolerance and operational concerns, testing practical application of architectural patterns alongside conceptual understanding of data modeling and real-time constraints.
System DesignOnsite - SnapchatHardSoftware EngineerDesign short URL service with click counting
This question tests the ability to design a distributed URL shortening service, focusing on system architecture, database partitioning, and strategies for high-frequency write operations like click tracking.
System DesignTechnical ScreenScalabilityDatabaseCaching - SnapchatHardSoftware EngineerParallelize the lock BFS safely
Parallelize the lock BFS safely 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 - SnowflakeMediumSoftware EngineerDesign a Cron Job Scheduler
This question evaluates skills in designing reliable distributed schedulers, including durable state modeling, concurrency and race-condition reasoning, idempotency, and fault-tolerant handoff semantics, and is commonly asked to assess a candidate's ability to guarantee correctness and coordination when multiple replicas must manage recurring job triggers. Categorized under system design and distributed systems with overlap into data modeling and consistency, it emphasizes practical application of architectural and operational trade-offs rather than purely theoretical concepts.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Distributed Job Scheduler with Cron, Pause and Resume
Design a job scheduler service that runs one-time and cron jobs, supports pausing and resuming, and dispatches work to an unlimited pool of workers. It tests due-job indexing, claim and lease protocols, pause semantics, at-least-once execution with idempotency, and handling top-of-the-hour spikes.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a Geolocation Search Service
This question tests your ability to design a scalable spatial indexing system capable of performing range-based queries (e.g., 'find all points of interest within 5km') while maintaining high availability and low latency.
System DesignTechnical ScreenGeolocationIndexingScalability - SnowflakeMediumSoftware EngineerDesign a Photo Album Backend: Upload Consistency, Deduplication and Scaling
A backend system design prompt for a photo album service where users upload photos and organize them into albums. It probes keeping a metadata database and blob storage consistent on upload, showing new photos instantly despite processing lag, blocking duplicate uploads, and when a relational database stops scaling.
System DesignOnsite - SnowflakeHardSoftware EngineerDesign a REST API Abstraction Layer
This question evaluates system design and API design competencies, focusing on creating a REST API abstraction layer and internal SDK that address cross-cutting concerns like reliability, observability, security, versioning, and contract/interface modeling.
System DesignTechnical Screen - SnowflakeHardSoftware EngineerDesign a Reliable Job Scheduler
This problem tests the ability to design a distributed, fault-tolerant job scheduler capable of handling task persistence, concurrency, and strict timing requirements at scale.
System DesignOnsiteDistributed SystemsConcurrencyFault Tolerance - SnowflakeMediumSoftware EngineerDesign a Shared User Quota Service That Never Overdraws
Design a quota service that several services draw from for each user, where the balance must never be overdrawn under highly concurrent requests and must stay strongly consistent. It tests atomic conditional updates, reserve-and-commit APIs with idempotency, replication choices, and scaling a single hot user's quota.
System DesignTechnical Screen - SnowflakeHardSoftware EngineerDesign a concurrent web crawler
This problem evaluates your ability to design a distributed, concurrent web crawling architecture that balances high throughput with politeness policies, concurrency control, and robust state management.
System DesignOnsiteConcurrencyDistributed SystemsCaching - SnowflakeEasySoftware EngineerDesign a disk-backed KV store under contention
This problem tests the ability to design a persistent key-value store that balances disk I/O, memory caching, and thread safety under high concurrency.
System DesignOnsiteConcurrencyStorage EnginesLSM Trees - SnowflakeHardSoftware EngineerDesign a distributed system end-to-end
This question evaluates a candidate's ability to design scalable, multi-tenant distributed analytics platforms, testing competencies in distributed systems architecture, data layout and storage, query planning and execution, metadata management, consistency and replication strategies, fault tolerance, observability, and capacity planning.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign a distributed tree node counter
Design a distributed tree node counter 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 - SnowflakeHardSoftware EngineerDesign a multi-tenant quota system
This question evaluates a candidate's ability to design a global multi-tenant quota service, testing competencies in distributed systems, data consistency, concurrency control, API and storage modeling, and scalability within the System Design domain.
System DesignTechnical Screen - SnowflakeMediumSoftware EngineerDesign an Audit Logs Service
Tests the ability to design an immutable, highly available, multi-tenant audit logging service that supports high-throughput ingestion and tamper-evident storage while providing fast, tenant-scoped querying.
System DesignTechnical ScreenDistributed SystemsSecurityMulti-Tenancy - SnowflakeMediumSoftware EngineerDesign an Interactive Query Execution Notebook
Tests your ability to design an asynchronous, scalable system for executing interactive SQL queries and streaming execution state and tabular results back to web clients.
System DesignTechnical Screensystem-designdistributed-systemsapi-design - SnowflakeMediumSoftware EngineerDesign an object store with deduplication
This question evaluates a candidate's ability to design scalable, durable object storage systems with deduplication, touching on storage architecture, data modeling, metadata management, consistency, and garbage collection.
System DesignTechnical Screen - SnowflakeHardSoftware EngineerDesign cache for DAG-based query views
This question evaluates a candidate's understanding of caching, consistency, versioning, eviction, and update propagation in DAG-based materialized views, testing competencies in distributed systems, data engineering, and storage-hierarchy design.
System DesignOnsite - SnowflakeHardSoftware EngineerDesign multi-core service startup scheduler
This question evaluates scheduling and resource-management skills, including DAG dependency handling, concurrency bounding, timeout/retry strategies, observability, and correctness reasoning for service startup orchestration.
System DesignOnsite - SnowflakeHardSoftware EngineerDesign under vague distributed requirements
This question evaluates expertise in distributed system architecture, metadata and schema management, transactional DDL semantics, consistency and replication strategies, API and data-model design, multi-tenant isolation, observability, security, and capacity planning.
System DesignTechnical Screen - SoFiHardSoftware EngineerDesign a Random Number Generation API
Design a Random Number Generation API 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 DesignOnsite - SoFiHardSoftware EngineerDesign a Real-Time Suggestions Service
Design a Real-Time Suggestions 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 DesignOnsite
Snapchat
Snowflake
SoFi