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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 241–270 of 1311 results
- 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 EngineerBuild AI-Assisted Full-Stack Transactions App
This question evaluates full‑stack engineering competencies including API design, data persistence, input validation, transactional integrity for monetary data, frontend-backend integration, automated testing, and developer documentation.
System DesignTechnical Screen - BrexHardSoftware EngineerDesign Points-from-Transactions Service
This question evaluates system design and distributed-systems competency, focusing on transaction processing, idempotency and deduplication, monetary precision and rounding, consistency models, data modeling, and operational controls like observability and fraud prevention.
System DesignTechnical Screen - 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 - BridgeMediumSoftware EngineerDesign signup and login service
This question evaluates understanding of authentication system design, secure password storage practices, API endpoint and request/response modeling, database schema design, and session or token-based login state management.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign An Ad Creative Relationship Processing System
This question tests your ability to design a distributed asynchronous processing pipeline that manages entity relationships, handles API retries, and maintains state consistency across multiple dependent components.
System DesignTechnical ScreenDistributed SystemsAsync ProcessingDatabase Schema - 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 - ByteDanceMediumData EngineerDesign a Data Service for Downstream Consumers
Design a centralized, governed data serving platform that provides downstream consumers with stable query APIs, schema evolution safety, cursor-based exports, and data freshness metadata.
System DesignHR ScreenData EngineeringAPI DesignData Governance - 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 Monitoring Dashboard with Explicit Latency Goals
Design a monitoring dashboard that separates data freshness from query latency, with ingestion, rollups, browser updates, and stale-data handling.
System DesignTechnical Screen - 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 - ByteDanceHardSoftware EngineerDesign a Synchronized Live Comment Overlay
Design a live comment overlay that stays synchronized with a video during live viewing, replay, seeking, and reconnects. Explore timeline semantics, stable ordering, scalable fanout, replay queries, moderation, backpressure, and graceful degradation during traffic bursts.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign a Ticket Booking System for High-Demand On-Sales Without Overselling
A system design question about a ticket booking system for high-demand on-sales. It probes how to absorb the traffic spike when sales open with load balancing, waiting rooms and rate limiting, and how to manage inventory with holds, payment-timeout release and consistent cache and database updates so that no ticket is ever sold twice.
System DesignTechnical Screen - 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 - ByteDanceHardSoftware EngineerDesign an E-Commerce Platform with Reliable Checkout
Design an e-commerce platform with searchable catalogs, carts, atomic inventory reservations, idempotent checkout, payment recovery, and reliable order state.
System DesignTechnical Screen - ByteDanceMediumSoftware EngineerDesign an RBAC Relational Schema
This problem tests your ability to design a normalized relational database schema that implements Role-Based Access Control (RBAC) to support hierarchical users, roles, and resource-level permissions.
System DesignTechnical ScreenSQLDatabase SchemaRBAC - ByteDanceMediumSoftware EngineerEvaluate a Migration from MySQL to MongoDB
Evaluate whether a MySQL-backed service should migrate to MongoDB using its actual workload and correctness needs. Compare relational and document models, joins and transactions, then outline a dual-run migration, rollback plan, and measurements that would prove an improvement.
System DesignTechnical Screen - 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 - 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 - 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 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 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
Box
Brex
C3 AI
Capital One