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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 721 results
- Booking.comMediumSoftware EngineerDesign a Real-Time Logging System
This question evaluates a candidate's competency in designing scalable, low-latency telemetry and logging systems, covering distributed systems architecture, ingestion pipelines, data modeling, real-time querying, reliability, backpressure, partitioning, indexing, retention, and operational trade-offs.
System DesignOnsite - BoxMediumSoftware EngineerDiagnose failures via SSH and large logs
Diagnose failures via SSH and large logs 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 - BoxHardSoftware EngineerExplain and diagram your past system architecture
Explain and diagram your past system architecture 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 - BoxMediumSoftware EngineerIdentify and fix deadlock in locked code
Identify and fix deadlock in locked code 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 - BrexMediumSoftware EngineerDesign a Peer-to-Peer Money Transfer System
Design a peer-to-peer money transfer product with accurate balances and history despite retries, crashes, and concurrent spending. Define APIs, transfer states, durable accounting, atomic movement, recovery, reconciliation, authorization, and the boundary between an in-memory prototype and production.
System DesignOnsite - ByteDanceMediumSoftware EngineerDesign Near-Real-Time Top Songs by Country
This question tests your ability to design a distributed streaming data pipeline that balances high-throughput ingestion with low-latency analytical queries for country-specific rankings.
System DesignOnsiteStreamingDistributed SystemsScalability - ByteDanceMediumSoftware EngineerDesign a Distributed Rate Limiter
This question tests the ability to design a scalable, low-latency rate limiting service that functions across multiple distributed application servers.
System DesignOnsiteDistributed SystemsCachingLatency - ByteDanceMediumSoftware EngineerDesign a High-Frequency Job Scheduler
This question tests your ability to design a distributed, high-frequency job scheduling system that handles millions of tasks with varying priorities while ensuring reliability and strict execution guarantees.
System DesignOnsiteDistributed SystemsScalabilityConcurrency - ByteDanceMediumSoftware EngineerDesign a Payment System: Time-Boxed High-Level Design
A time-boxed system design question asking for a high-level payment system that charges users through an external payment provider. It tests the end-to-end checkout flow, idempotent retries, a payment state machine and ledger, asynchronous provider notifications, reconciliation and failure handling.
System DesignOnsite - ByteDanceMediumSoftware EngineerDesign a Real-Time Auction Platform
This question evaluates a candidate's ability to design a real-time, high-throughput distributed system focusing on API design, concurrency control, ordering guarantees, idempotency, persistence of bid history and state transitions, and real-time push/update mechanisms.
System DesignOnsite - ByteDanceMediumSoftware EngineerDesign a payment system with real-time holds, batch settlement and safe retries
System design question: design a payment system that places real-time holds on funds and settles them in batches, then explain how retries avoid double charges. It probes idempotency at every hop, payment state machines, double-entry ledgers, consistency across an external processor, reconciliation, and recovery from specific failures.
System DesignOnsite - ByteDanceMediumSoftware EngineerModel Campaigns, Targeting, and Edit History for a Demand-Side Ad Platform
Model a demand-side ad platform with advertisers, campaigns, ad groups, ads, and creatives, including audience rules, edit history, and versioned publishing.
System DesignOnsite - C3 AIEasySoftware EngineerDesign a restaurant reservation system
This question evaluates skills in system architecture and engineering, including data modeling, API design, concurrency control to prevent double-booking, availability and scheduling logic, scalability under traffic spikes, and operational concerns like auditability and low-latency queries.
System DesignOnsite - Capital OneMediumSoftware EngineerDesign a highly reliable account balance system
This question evaluates a candidate's ability to architect a highly reliable transactional account-balance service, testing competencies in data modeling and storage choice, API design for idempotency, concurrency and consistency mechanisms, replication/failover, partitioning for scale, and auditability.
System DesignOnsite - Capital OneHardSoftware EngineerDesign a scalable banking system
This question evaluates system design skills focused on distributed systems architecture, transactional integrity, strong consistency models, security and authentication, external payment and ATM integrations, data modeling, API design, concurrency control, and operational monitoring for financial platforms.
System DesignOnsite - Capital OneMediumSoftware EngineerDesign an Enterprise Agent Platform with Guardrails and Latency Control
Design an enterprise agent platform with durable execution, deliberate workflow-versus-agent choices, enforceable tool guardrails, and a dependency-aware latency plan.
System DesignOnsite - Capital OneMediumMachine Learning EngineerValidate virtual credit card transactions from encoded IDs
This question evaluates understanding of virtual credit card product trade-offs and the ability to design data models and deterministic validation logic for encoded transaction attributes, testing competencies in payment systems, data encoding/decoding, and rule-based validation.
System DesignOnsite - CarvanaEasySoftware EngineerDesign an Attendance Payroll Service
This question evaluates system design and backend engineering skills, including API design, data modeling for time-series attendance, payroll computation logic, consistency guarantees, integration/synchronization with external sources, and strategies for handling high-volume, bursty traffic.
System DesignOnsite - Charta HealthMediumSoftware EngineerGenerate Consistent Outputs for Similar Inputs
Design a semantic caching and computation deduplication system that identifies similar inputs, prevents duplicate expensive processing under concurrent load, and maintains consistent, versioned outputs.
System DesignOnsiteDistributed SystemsCachingVector Search - Chicago Trading CompanyMediumSoftware EngineerDesign a Pre-Trade Risk Check for an Electronic Order Path
This question tests the ability to design a high-throughput, low-latency risk engine capable of atomic exposure validation before orders reach an exchange, while balancing concurrency and strict fault tolerance.
System DesignOnsiteLow LatencyConcurrencyRisk Management - ChimeHardSoftware EngineerDesign mobile check deposit system
This question evaluates a candidate's ability to design end-to-end, production-grade mobile check deposit systems, assessing competencies in system architecture, distributed systems, security and fraud prevention, regulatory compliance (Reg CC, Check 21), data durability, and operational observability.
System DesignOnsite - CitadelMediumSoftware EngineerDesign a Course Registration System
Design a course registration system with relational models and APIs for enrollment, dropping, schedules, waitlists, and course browsing. The solution explains transactional capacity protection, idempotent retries, re-enrollment without duplicate rows, FIFO promotion, outbox notifications, and tests for final-seat races.
System DesignOnsite - CitadelMediumSoftware EngineerDesign a Low-Latency Metrics and Alerting Platform
Design a high-throughput, multi-tenant metrics ingestion and alerting engine capable of triggering critical alerts within two seconds. The question evaluates your knowledge of streaming architectures, time-series storage, cardinality management, and fault-tolerant notification delivery.
System DesignOnsiteTime SeriesDistributed SystemsStreaming - CitadelHardSoftware EngineerDesign a low-latency trading platform
This question tests the ability to architect a high-throughput, sub-millisecond trading system while balancing strict deterministic latency requirements with necessary safety checks.
System DesignOnsiteHFTLow-LatencyConcurrency - CitadelMediumSoftware EngineerDesign alerting for application-to-exchange mappings
This question evaluates understanding of real-time stream processing, alerting policy design, and distributed state coordination for application-to-exchange mappings, testing competencies in scalability, correctness under partitioning and duplication, and efficient aggregation of high-volume event streams.
System DesignOnsite - CitadelMediumSoftware EngineerDesign an Authenticated Online Shopping Service
Design an authenticated online shopping service with secure signup and login, user-owned carts, product browsing, and retry-safe order creation. The solution covers password hashing, session rotation, CSRF defenses, resource-level authorization, idempotency keys, immutable order snapshots, recovery tokens, and horizontal-access tests.
System DesignOnsite - CitiMediumSoftware EngineerExplain OS and networking basics
This question evaluates a candidate's understanding of operating system and networking fundamentals, covering processes, threads and context switching, concurrency versus parallelism, TCP/UDP and flow versus congestion control, and the end-to-end web request and browser rendering pipeline.
System DesignOnsite - ClickupMediumSoftware EngineerDesign weekly comment digest
This question evaluates understanding of scalable system architecture, integration with external ML services, handling rate limits, reliable scheduling and delivery, data modeling for aggregation and deduplication, and fault-tolerant ranking under load.
System DesignOnsite - CloudKitchensMediumSoftware EngineerDesign real-time kitchen order fulfillment system
This question evaluates a candidate's competency in designing real-time backend systems, emphasizing concurrency control, stateful resource allocation, time-sensitive freshness constraints, efficient eviction policies, and action logging.
System DesignOnsite - CloudflareMediumSoftware EngineerDesign an encrypted log collection system
This question tests the ability to design a distributed, high-throughput ingestion pipeline that ensures log confidentiality and integrity using encryption at rest and in transit.
System DesignOnsiteSecurityDistributed SystemsEncryption
Booking.com
Box
Brex
C3 AI
Capital One
Chime
Citadel
Citi
Cloudflare