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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 121–150 of 517 results
- ByteDanceMediumSoftware EngineerPrevent a Cache Stampede on a Hot Key
This question tests the ability to design robust cache-aside mechanisms to prevent database overload during cache expiration events for high-traffic keys.
System DesignTechnical ScreenCachingDistributed SystemsHigh Availability - ByteDanceMediumSoftware EngineerTrace and Debug Agent Tool-Call Failures
Design a distributed observability and tracing system to monitor, debug, and diagnose multi-step agent tool-call failures across retries and execution stages without leaking sensitive data.
System DesignTechnical ScreenDistributed TracingObservabilityAI Agents - Capital OneMediumSoftware EngineerCard Issuer Backend: Fast Purchase Approvals and a Secure PII Vault
Design the issuer-side platform that approves or declines card purchases in tens of milliseconds, settles them later, and stores cardholder identity data so a breach of any one service exposes as little as possible.
System DesignTechnical Screensystem-designpaymentslatency - Capital OneMediumSoftware EngineerDesign a Buy-Now-Pay-Later Checkout Backend: Latency and PII Storage
Design the backend of a buy-now-pay-later checkout financing service that approves or declines a purchase in real time against a shopper's revolving credit line, then go deep on latency budgeting for the decision and on securely storing borrowers' personal data.
System DesignTechnical Screensystem-designfintechconcurrency - Capital OneMediumSoftware EngineerDesign a Credit Card System: Authorization Latency and Sensitive Data Storage
A system design question that asks for the backend of a credit card system, then goes deep on what payment authorization latency is reasonable and how to achieve it, and on how to store cardholders' sensitive personal information. It tests transaction flow design, available-credit concurrency, latency budgeting, and data protection.
System DesignTechnical Screen - Capital OneMediumSoftware EngineerDesign a Credit Card System: Authorization, Fraud, Bureau Reports, Limit Increases
A system design question for a credit card platform covering customer login, real-time payment authorization with fraud checks, monthly credit bureau reporting, a spending overview, and instant credit limit increase decisions. It tests laying out entities, services and read and write paths before choosing deep dives.
System DesignTechnical Screen - Capital OneMediumData EngineerEvaluate credit-limit increase profitability
This question evaluates a data engineer's competency in business analytics, unit-economics P&L modeling, risk-versus-revenue trade-off analysis, and experiment-driven evaluation of credit product changes.
System DesignTechnical Screen - CerebrasHardSoftware EngineerDesign a Multi-Channel Message Queue
This question evaluates understanding of data modeling for multi-tag messages, set-based subscription semantics, scalable system design, and algorithmic complexity for operations such as enqueue, dequeue, subscribe/unsubscribe, and intersection queries.
System DesignTechnical Screen - ChimeEasySoftware EngineerDesign load balancing, caching, and idempotent APIs
This question evaluates a candidate's competency in designing scalable, reliable backend architectures, specifically focusing on load balancing strategies, multi-layer caching, and idempotent API design.
System DesignTechnical Screen - CitadelMediumSoftware EngineerDesign Inventory Availability and Order Placement
Design e-commerce inventory availability and order reservation without overselling under concurrent requests. Define on-hand, reserved, and available invariants; atomic multi-item placement; idempotent retries; expiration; and optimistic versus pessimistic control for hot SKUs.
System DesignTechnical Screen - CitadelHardSoftware EngineerDesign a low-latency trading system
This question evaluates expertise in designing low-latency, high-determinism electronic trading systems, covering order matching, market data ingestion and publish, partitioning/sharding, persistence for auditability, idempotency, pre-trade risk controls, and operational reliability.
System DesignTechnical Screen - CitadelHardSoftware EngineerDiscuss queues, NoSQL, and concurrency
This question evaluates understanding of distributed messaging systems, delivery semantics, push versus pull consumption models, NoSQL versus relational storage trade-offs, and concurrency control including deadlock concepts.
System DesignTechnical Screen - CohereMediumSoftware EngineerAnswer Enterprise Questions Across Internal and External Sources
Design enterprise AI question answering across internal and external sources with permission-aware retrieval, entity mapping, evidence-grounded synthesis, and freshness controls.
System DesignTechnical Screen - CoinbaseMediumSoftware EngineerDesign a blob storage system for lunar environment
This question evaluates system design and distributed storage competencies, focusing on durability, replication, metadata management, consistency, and trade-offs under resource-constrained, high-latency conditions; it is in the System Design category and tests knowledge across distributed systems, storage architecture, and networking.
System DesignTechnical Screen - CoinbaseMediumSoftware EngineerDesign a food delivery system
This problem tests your ability to design a distributed, real-time logistics platform, focusing on high-concurrency order placement, real-time courier tracking, and transactional integrity during payment and dispatch.
System DesignTechnical ScreenScalabilityReal-timeGeospatial - CommureMediumSoftware EngineerDesign Monthly Artist Payouts from Streaming Counts
Design a monthly artist-payout system that turns valid streaming events into reproducible obligations and idempotent external payments. The answer covers event deduplication, period closure, payout versions, timeout ambiguity, outbox delivery, provider reconciliation, late adjustments, and auditable financial state.
System DesignTechnical Screen - ConfluentHardSoftware EngineerDesign a distributed key-value store at scale
Design a distributed key-value store at scale 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 - ConfluentHardSoftware EngineerDesign a temporary email service
This question evaluates a candidate's ability to design scalable, highly available, and privacy-focused email ingestion systems, probing competencies in distributed systems, networking (SMTP/MX), storage lifecycle management, rate limiting, security/privacy, and observability.
System DesignTechnical Screen - CrestaEasySoftware EngineerProductionize a Successful Proof of Concept
Explain how to take a successful proof of concept into production, including the engineering and operational gaps that must be closed.
System DesignTechnical Screen - CrowdstrikeMediumSoftware EngineerDesign scalable worker pool for template jobs
This question evaluates a candidate's competency in designing scalable, concurrent backend systems, covering distributed worker pools, producer–consumer patterns, queuing, load balancing, fault tolerance, backpressure, and domain-specific considerations like template parsing and caching.
System DesignTechnical Screen - CurrentHardSoftware EngineerDesign a metrics monitoring system
Design a metrics monitoring 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 - CursorMediumBackend EngineerDesign Scalable Notification Rate Limiter
This question evaluates expertise in designing distributed rate-limiting systems with hierarchical quotas, focusing on concurrency control, exact rolling-window counting, and correctness under concurrent stateless servers; it belongs to the System Design domain and tests practical application of distributed systems, storage, and API design as well as conceptual understanding of atomicity and consistency. It is commonly asked to assess reasoning about atomic decision-making across multiple scopes, scalability and partitioning strategies, handling reconfiguration and operational concerns, and the trade-offs between correctness and system performance (English).
System DesignTechnical Screen - CursorMediumSoftware EngineerDesign Versioned IDE Settings for Users and Teams
Design a distributed, hierarchical configuration management service for an IDE that synchronizes versioned settings across individual users, multiple teams, and workspaces while supporting offline modifications and deterministic conflict resolution.
System DesignTechnical ScreenDistributed SystemsOffline SyncData Modeling - CursorMediumSoftware EngineerDesign a Durable Cron Job Scheduler
Design a cron scheduler with durable occurrences, timezone rules, missed-run policies, worker leases, idempotent dispatch, and failure recovery.
System DesignTechnical Screen - DatabricksMediumSoftware EngineerDesign Chat Deletion Semantics Under Concurrent Sends
Design the data consistency, concurrency control, and deletion semantics for a distributed chat platform when message creation and thread deletion occur concurrently across distributed nodes.
System DesignTechnical ScreenDistributed SystemsConcurrencyData Consistency - DatabricksMediumSoftware EngineerDesign KV store with sliding-window QPS metrics
This question tests the ability to design an in-memory key-value store that supports basic operations while maintaining accurate sliding-window QPS (queries per second) metrics.
System DesignTechnical ScreenConcurrencyData StructuresMetrics - DatabricksMediumSoftware EngineerDesign a Book Price Aggregator
Tests the ability to architect a resilient aggregation system interfacing with heterogeneous, unreliable third-party APIs under strict latency, rate-limiting, and cache consistency constraints.
System DesignTechnical Screensystem-designdistributed-systemscaching - DatabricksMediumSoftware EngineerDesign a Chat Application with a Partitioned Cache
Design an end-to-end direct and small-group messaging system with strict delivery guarantees, message ordering, and an explicitly partitioned multi-tier caching layer.
System DesignTechnical ScreenDistributed CachingReal-Time MessagingData Partitioning - DatabricksMediumBackend EngineerDesign a Distributed File System
This question tests the ability to design a scalable, fault-tolerant distributed file system by addressing challenges in metadata management, data chunking, and cluster availability.
System DesignTechnical ScreenDistributed SystemsStorageScalability - DatabricksHardSoftware EngineerDesign a KV store with QPS API
This question tests the ability to design a distributed key-value store architecture that incorporates observability, specifically tracking per-key or per-prefix Queries Per Second (QPS) metrics in real-time.
System DesignTechnical ScreenDistributed SystemsObservabilityCaching
Capital One
Cerebras
Chime
Citadel
Cohere
Coinbase
Confluent
Cresta
Crowdstrike
Cursor
Databricks