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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 1081–1110 of 1311 results
- RobinhoodMediumSoftware EngineerDesign a job scheduler with SLA and logs
This question tests the ability to design a distributed, fault-tolerant job scheduling system capable of meeting strict SLAs and providing audit-ready logging.
System DesignTechnical ScreenDistributed SystemsTask QueuesScalability - RobinhoodMediumSoftware EngineerDesign a live and historical stock quote API fed by a redundant exchange trade feed
A system design question that asks for a stock quote API serving live prices at about 10 million requests per second and one-day, one-month and one-year history at about 1 million, fed by two redundant exchange trade connections. It tests sequence-number arbitration, gap replay, fan-out of live state, bar aggregation and caching at scale.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign a secure trading app on AWS
This System Design question evaluates secure cloud-based architecture on AWS, covering competencies in authentication and authorization, PII handling and auditability, API and data model design, and scalable low-latency market-data retrieval.
System DesignTechnical Screen - RobinhoodMediumSoftware EngineerDesign an At-Most-Once Job Scheduler
This question tests the ability to design a distributed, fault-tolerant job scheduler that guarantees tasks are executed no more than once, focusing on state management and concurrency control.
System DesignOnsiteDistributed SystemsConcurrencyFault Tolerance - RobinhoodMediumSoftware EngineerDesign an Order Execution System for Market and Limit Orders with Cancellation
A system design question about building the order execution system for a retail brokerage, where users place market and limit orders and can cancel them. It tests order execution flow, order state transitions with partial fills and cancels, failure handling, tracking user balances, and scaling the design to millions of orders.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign authorization and audit logging systems
This question tests your ability to design a scalable, low-latency authorization framework and a reliable, tamper-proof audit logging system for a financial platform.
System DesignOnsiteSecurityAuthorizationAudit Logging - RobinhoodMediumBackend EngineerScale Word-Frequency Processing Beyond One Machine
This question tests the ability to design a distributed data processing pipeline that handles large-scale text files by balancing memory constraints, horizontal scalability, and data integrity.
System DesignTechnical ScreenDistributed SystemsMapReduceScalability - RobloxEasySoftware EngineerDesign Multi-Dimensional Request Rate Limiting
Design a distributed, low-latency rate limiting service capable of enforcing multi-dimensional limits (e.g., by user ID, IP address, and endpoint) across a large-scale gaming platform.
System DesignTechnical ScreenDistributed SystemsRate LimitingCaching - RobloxHardSoftware EngineerDesign a Played-By Summary System
Design a scalable social-proof service that tracks unique player counts per experience and computes real-time friend-intersection summaries under high write throughput and low read latency.
System DesignTechnical Screensystem-designdistributed-systemscaching - RobloxMediumSoftware EngineerDesign a Real-Time Shared To-Do List
Design a real-time collaborative to-do list supporting concurrent edits, task reordering, fast write confirmations, and seamless reconnect recovery.
System DesignTechnical ScreenReal-TimeWebSocketsDistributed Systems - RobloxMediumFrontend EngineerDesign a Reusable Dropdown Menu Component
Tests a candidate's ability to architect a production-grade, reusable UI component library element with consideration for flexible API design, accessibility (WAI-ARIA), state management, and large dataset performance.
System DesignOnsiteFrontend System DesignReactAccessibility - RobloxMediumSoftware EngineerDesign a Scalable Like Counter
This question tests the ability to design a high-throughput, eventually consistent counting system that handles massive concurrent write volumes while maintaining low-latency read access.
System DesignOnsiteScalabilityDistributed SystemsCaching - RobloxMediumSoftware EngineerDesign a Scalable Likes System
This question tests your ability to design a high-throughput, distributed service for tracking user engagement, focusing on write-heavy loads and read-consistency trade-offs.
System DesignTechnical ScreenScalabilityDistributed SystemsCaching - RobloxMediumSoftware EngineerDesign a rate limiter
This problem tests your ability to design a distributed rate-limiting service that maintains request counts across multiple application nodes while balancing system performance and accuracy.
System DesignTechnical ScreenScalabilityDistributed SystemsCaching - RobloxHardSoftware EngineerDesign a scheduled payment system
This question evaluates proficiency in designing a reliable, scalable scheduled payment service, testing competencies in distributed systems, API design, scheduling and execution workflows, idempotency and deduplication, time semantics, transactional consistency, security and compliance, and operational monitoring.
System DesignOnsite - RobloxMediumSoftware EngineerDesign an In-App Notification Center with Real-Time Updates and Unread Counts
A system design question about an in-app notification center that turns product events into per-user notifications, shows an unread badge and a recent list, and pushes new items to online users. It tests fan-out strategy, inbox data modeling, unread counts, real-time delivery, reliability, and client design.
System DesignOnsite - RobloxMediumSoftware EngineerDesign favorites and social game recommendations
This question tests the ability to design a scalable, low-latency system for managing user-specific lists (favorites) and integrating real-time social signals into a game recommendation engine.
System DesignOnsiteScalabilityCachingSocial Graphs - RobloxMediumSoftware EngineerDesign in-game payment wallet system
Design in-game payment wallet system 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 - RobloxHardSoftware EngineerDesign real-time game matchmaking service
This question evaluates a candidate's competence in designing scalable, low-latency distributed systems and matchmaking algorithms, including skills in queue management, skill-based matching, regional sharding, SLO-driven latency targets, consistency models, failure handling, and monitoring.
System DesignOnsite - RobloxHardSoftware EngineerDesign resource loader and ROS-like pub/sub
This question evaluates system design and distributed-systems competencies including resource management, async concurrency, caching and eviction, streaming and partial loads, dependency resolution, failure isolation, observability, and pub/sub concerns such as topic/schema/versioning, discovery, QoS, ordering, replay, partitioning, latency, clock semantics, and security. Commonly asked to assess architectural reasoning about scalability, low-latency trade-offs, fault tolerance, and deployment/topology choices, it is categorized under System Design and tests both high-level conceptual understanding and practical application-level design decisions; English.
System DesignOnsite - RokuMediumBackend EngineerDesign a high-throughput ad exchange
This problem tests your ability to design a low-latency, high-throughput distributed system capable of managing real-time bidding (RTB) auctions for streaming video advertisements.
System DesignOnsiteDistributed SystemsLow LatencyHigh Throughput - RokuMediumSoftware EngineerDesign a video-on-demand streaming service
This problem tests your ability to design a distributed video-on-demand platform, focusing on content ingestion, delivery at scale, and media processing pipelines.
System DesignOnsiteScalabilityCDNDistributed Systems - SalesforceHardSoftware EngineerArchitect serving and storage for recommender
Architect serving and storage for recommender 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 - SalesforceMediumSoftware EngineerDesign a 911 emergency calling service
This question evaluates a candidate's ability to design a highly available, scalable emergency-calling platform covering real-time call flow, accurate caller location validation, PSAP routing, interoperability with telephony/SIP providers, and regulatory/security considerations.
System DesignOnsite - SalesforceEasyBackend EngineerDesign a Chat Analytics Backend
This question evaluates a candidate's competence in designing large-scale analytics backends, covering data ingestion, event and metric schemas, near-real-time and historical analytics, metric computation and slicing, data freshness and deduplication, privacy and access control, operational monitoring, and the API/query layer.
System DesignOnsite - SalesforceMediumSoftware EngineerDesign a Coffee-Shop Order-Management System
Design a distributed order-management system for a multi-location coffee shop chain, focusing on transactional order states, menu snapshotting, idempotent payment processing, and resilient preparation workflows.
System DesignOnsitesystem-designdistributed-systemspayments - SalesforceMediumSoftware EngineerDesign a Concurrent Car Reservation Service
Design a concurrent car reservation service with availability search, temporary holds, confirmation, cancellation, and status lookup. Explain interval conflicts, atomic inventory claims, retry safety, hold expiry, stale search results, substitutions, partitioning, and double-booking prevention.
System DesignOnsite - SalesforceMediumSoftware EngineerDesign a Multi-Tenant Enterprise Messaging System
Design a multi-tenant enterprise messaging system with direct messages, multiple channel types, durable history, real-time delivery, offline catch-up, search, presence, and read positions. Explain ordering, permissions, fan-out, storage, and strict tenant isolation.
System DesignOnsite - SalesforceMediumSoftware EngineerDesign a Multi-Vendor Integration Platform
Design a multi-vendor integration platform for authorized actions and inbound events across providers with different APIs. Define an extensible connector contract, secure credential handling, durable retries, rate isolation, webhook and polling ingestion, deduplication, and schema evolution.
System DesignOnsite - SalesforceMediumSoftware EngineerDesign a Ride-Hailing Platform: Driver Matching, Surge Pricing and Ride Acceptance
Design the core of a ride-hailing platform, covering driver location ingestion, matching riders with nearby drivers, the offer and acceptance flow with timeouts and reassignment, and surge pricing per area. It tests geospatial indexing, state machines and consistency under concurrent updates.
System DesignOnsite
Robinhood
Roblox
Salesforce