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Software Engineer 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 151–180 of 2810 results

  • AmazonEasySoftware Engineer
    Design a Scalable News Feed

    This problem evaluates your ability to design a feed generation architecture, specifically comparing push vs. pull models for users with varying follower counts.

    System DesignTechnical ScreenCachingScalabilityDatabases
  • AmazonMediumSoftware Engineer
    Design a basic credit card system

    This problem tests object-oriented modeling and state management by requiring the design of a class structure that handles credit limits, transaction authorization, and balance tracking.

    Software Engineering FundamentalsTechnical ScreenObject-Oriented DesignDomain ModelingSystem Architecture
  • AmazonHardSoftware Engineer
    Design a cloud database write path and recovery

    This question tests the ability to architect a distributed database write path that decouples compute from storage, specifically focusing on how to maintain ACID properties during failures.

    System DesignTechnical ScreenDistributed SystemsDatabasesDurability
  • AmazonHardSoftware Engineer
    Design a fraud detection system

    This problem evaluates your ability to design a scalable, low-latency fraud detection system for an e-commerce platform, focusing on handling class imbalance, feature engineering, and the challenges of delayed feedback loops.

    ML System DesignTechnical ScreenFraud DetectionScalabilityFeature Store
  • AmazonMediumSoftware Engineer
    Design a hierarchical locking tree

    This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Design a hierarchical locking tree states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsTechnical Screen
  • AmazonHardSoftware Engineer
    Design a keyboard and mouse input system

    An Amazon software-engineer system-design screen: design a system that captures keyboard and mouse events and reconstructs exactly what the user typed. It tests low-latency event capture, total ordering across multiple devices, IME/composition and grapheme-safe text reconstruction, mouse selection and clipboard/undo-redo, plus durable persistence with deterministic crash-safe replay.

    System DesignTechnical Screen
  • AmazonMediumSoftware Engineer
    Design a large-scale temperature sensor system

    This question tests your ability to design a high-throughput data ingestion pipeline and storage architecture for a fleet of IoT sensors, focusing on write-heavy scalability and time-series query performance.

    System DesignTechnical ScreenTime-SeriesScalabilityDistributed Systems
  • AmazonHardSoftware Engineer
    Design a log filtering and analytics service

    An Amazon software engineer system design question: design a log filtering and analytics service that ingests high-volume application logs and supports attribute/substring filtering, error counts over a time window, and hourly histograms by pattern or ID. It tests ingestion API design, dual search + OLAP storage with hourly rollups, schema and indexing, late/duplicate-event handling, partitioning and retention, and correctness-vs-latency trade-offs with complexity analysis.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design a memory usage switcher with thresholds

    This question evaluates system design and operational engineering skills in process memory management, runtime configurability, observability, and reliability, and belongs to the System Design domain; it primarily tests practical application with system-level conceptual reasoning.

    System DesignTechnical Screen
  • AmazonMediumSoftware Engineer
    Design a package installer with dependencies

    This question tests your ability to design a system that manages complex dependency graphs, ensuring package integrity, version compatibility, and atomic installation operations.

    System DesignTechnical ScreenGraphsDependency ResolutionTransactions
  • AmazonMediumSoftware Engineer
    Design a pizza ordering system

    This question evaluates object-oriented design and software architecture skills, focusing on class modeling, responsibilities, relationships, state management, pricing, payment flows, and extensibility.

    Software Engineering FundamentalsTechnical Screen
  • AmazonHardSoftware Engineer
    Design a scalable parking lot system

    Design a scalable parking lot 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
  • AmazonMediumSoftware Engineer
    Design a weighted random value generator

    This problem tests your ability to implement efficient weighted random selection using prefix sums and binary search, and handling state updates.

    Coding & AlgorithmsTechnical ScreenBinary SearchHash MapProbability
  • AmazonMediumSoftware Engineer
    Design an AI Fraud-Triage Agent Over a 1 TB/Day Payments Event Stream

    Design a service where an AI agent investigates flagged payment events inside a stream running at roughly 1 TB of events per day, covering capacity math, where the agent sits relative to deterministic detection, and the cost and adversarial-input guardrails that keep it from becoming a liability.

    System DesignTechnical Screensystem-designstreamingfraud
  • AmazonEasySoftware Engineer
    Design an Amazon Locker Service

    Tests object-oriented design and state-machine modeling for a self-service package locker station, focusing on parcel allocation, code expiration, and physical-vs-logical state consistency.

    System DesignTechnical ScreenObject-Oriented DesignState MachineIoT
  • AmazonMediumSoftware Engineer
    Design an Extensible Cinema Ticket Pricing Engine

    Design an extensible cinema pricing engine with validated money and multiplier types, composable policies, explicit calculation and rounding, compatibility checks, versioned configuration, itemized quotes, and boundary tests.

    Software Engineering FundamentalsTechnical Screen
  • AmazonMediumSoftware Engineer
    Design an In-Memory Pub-Sub Model

    This question evaluates object-oriented design and API modeling skills, knowledge of messaging/pub-sub semantics, concurrency and thread-safety, and the ability to reason about extensibility for retries, persistence, and asynchronous delivery.

    Software Engineering FundamentalsTechnical Screen
  • AmazonMediumSoftware Engineer
    Design an Object-Oriented Shopping Cart

    Tests object-oriented design principles, domain modeling for monetary precision, extensible discount strategies, and thread-safe state mutations.

    Software Engineering FundamentalsTechnical ScreenObject-Oriented DesignDesign PatternsConcurrency
  • AmazonHardSoftware Engineer
    Design an e-commerce recommendation system

    This question evaluates expertise in large-scale machine learning system design, covering competencies in recommendation algorithms, candidate generation and ranking, feature engineering and stores, low-latency serving, and operational reliability; it is categorized in the ML system design domain and requires both conceptual understanding and practical application. It is commonly asked to assess the ability to balance personalization and business metrics (CTR, CVR, revenue), address scalability and latency targets, and manage data quality, cold-start, exploration–exploitation, A/B testing, bias/fairness, and monitoring trade-offs in production.

    ML System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design an email spam detection system

    This interview question evaluates ML product requirements, data/labeling, modeling, serving architecture, evaluation, monitoring, and trade-offs in a realistic interview setting. A strong answer for Design an email spam detection system states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    ML System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design an extensible ticketing system

    This question evaluates software architecture and system-design competencies, covering extensibility patterns, concurrency control for high-throughput ticketing, transactional and idempotency guarantees, persistence/schema modeling, API design, and pluggable pricing strategies.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design an intersection traffic-light system

    This question evaluates system design competency across real-time control and safety-critical logic, API and data modeling, sensor/actuator integration, and operational scalability for traffic-signal controllers.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design in-memory threshold switcher

    This question evaluates a candidate's ability to design memory-aware control systems, covering skills such as hysteresis-based thresholding, dynamic runtime reconfiguration, thread-safe concurrency, low-overhead metric sampling, event-driven state notifications, and handling multi-process and failure edge cases.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design locker allocation service

    This question evaluates a candidate's understanding of stateful system design, resource allocation strategies, concurrency control, API and data modeling, and fault tolerance in the context of real-time locker assignment.

    System DesignTechnical Screen
  • AmazonMediumSoftware Engineer
    Design pickup point planning for ride-hailing

    Design a ride-hailing pickup-point planning system. Covers map snapping, candidate generation, driver and passenger routing, safety filtering, scoring objectives, app presentation, architecture, historical learning, and A/B metrics.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design real-time top-K products service

    An Amazon software-engineer system-design screen: design a real-time service that ingests a stream of purchase events (customer_id, item_id, timestamp) and continuously serves the top-K most purchased items over multiple rolling windows (e.g. last 5 minutes, last 1 hour, 24 hours, and daily totals). The answer covers ingestion and partitioning, event-time windowing with watermarks, exact min-heap vs. approximate Count-Min-Sketch / Space-Saving top-K, late/duplicate/out-of-order handling, state and TTL, exactly-once fault tolerance, horizontal scaling, serving APIs, and latency-vs-accuracy trade-offs.

    System DesignTechnical Screen
  • AmazonHardSoftware Engineer
    Design secure multi-tier cloud infrastructure

    This question evaluates cloud systems design competencies including multi-tier network architecture, IP addressing and capacity planning, security controls, centralized server management, shared storage trade-offs, and identity and access integration within a production-scale virtual private cloud.

    System DesignTechnical Screen
  • AmazonMediumSoftware Engineer
    Detect and Break a Cycle in a Singly Linked List

    Tests detection and resolution of cycles in singly linked lists using two-pointer techniques with constant auxiliary space.

    Coding & AlgorithmsTechnical Screenlinked-listtwo-pointersfloyds-algorithm
  • AmazonMediumSoftware Engineer
    Detect cycles in lists and graphs

    This question evaluates understanding of cycle detection in linked lists and directed graphs, assessing competencies in pointer manipulation, graph traversal strategies, and reasoning about algorithmic time and space complexity within the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen
  • AmazonMediumSoftware Engineer
    Detect words formed by multiple dictionary parts

    This question evaluates proficiency in string processing, selection and use of appropriate data structures and algorithms (hashing, tries), dynamic programming and memoization, and complexity analysis for large inputs and edge-case handling within the Coding & Algorithms domain.

    Coding & AlgorithmsTechnical Screen