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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 181–210 of 3640 results
- AmazonMediumSoftware EngineerDesign a Threshold-Based Database Partition Rebalancer
This problem tests your ability to design a distributed system component that maintains cluster balance by dynamically splitting and merging data shards based on size thresholds.
Software Engineering FundamentalsOnsiteDistributed SystemsSystem DesignConcurrency - AmazonMediumSoftware EngineerDesign a Train Fare Calculator with Dynamic Stations and a Weekend Fare Cap
An object-oriented design and coding exercise for a train line where each segment between adjacent stations costs one unit. It asks for a fare function between two stations, a route class that loads route data and supports adding stations at runtime, and a weekend rule that caps the total fare.
Software Engineering FundamentalsOnsite - AmazonHardSoftware EngineerDesign a URL shortening platform
This question evaluates competency in system design and distributed systems architecture, including API design, scalable short-code generation, data modeling and storage/sharding, caching and CDN strategies, consistency and fault-tolerance trade-offs, rate limiting and abuse prevention, analytics, compliance, and capacity planning.
System DesignOnsite - AmazonMediumApplied ScientistDesign a computer-use agent end-to-end
This problem evaluates your ability to design a multimodal agent capable of interpreting UI elements and executing sequences of actions to complete user-defined tasks on a computer screen.
ML System DesignOnsiteVLMReinforcement LearningMultimodal - AmazonHardSoftware EngineerDesign a configuration subscription service
This question evaluates skills in designing a distributed configuration and subscription service, covering API design, real-time notification semantics (delivery and ordering guarantees), versioning, concurrency and thread-safety, durability and recovery, multi-tenant isolation, security, and scalability concerns.
System DesignOnsite - AmazonHardSoftware EngineerDesign a distributed job scheduler service
This question tests the ability to design a distributed, fault-tolerant system capable of scheduling and executing tasks at a massive scale with strict latency requirements.
System DesignOnsiteDistributed SystemsScalabilityScheduling - AmazonHardSoftware EngineerDesign a file search module like UNIX find
This question evaluates object-oriented and API design skills, filesystem semantics (pattern matching, file types, timestamps, permissions, symlink handling), traversal and concurrency strategies, and robustness for large or error-prone directory trees.
System DesignOnsite - AmazonMediumSoftware EngineerDesign a fixed-capacity circular queue
This question evaluates understanding of fixed-capacity circular queue data structures, array-based indexing, modular arithmetic, and the requirement for constant-time (O(1)) enqueue/dequeue operations.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerDesign a multi-size storage locker system
This question tests your ability to design a scalable, distributed reservation system that handles resource allocation (bin packing) under concurrency constraints.
System DesignOnsiteConcurrencyAPI DesignDistributed Systems - AmazonMediumSoftware EngineerDesign a no-repeat top-frequency music player
Design a no-repeat frequency-based music player with addUserSongs and getNextSong APIs. Covers max-heap data structures, lazy deletion, cycle resets, mid-cycle song additions, and complexity.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerDesign a scalable image-based social network
This question tests your ability to design a distributed system architecture capable of handling high-volume image uploads, metadata storage, and low-latency feed retrieval.
System DesignOnsiteScalabilityDistributed SystemsCaching - AmazonMediumData ScientistDesign an A/B Test for Dashboard Engagement Impact
Amazon data scientist experimentation prompt on designing an A/B test for an energy-usage dashboard redesign, including hypotheses, metrics, guardrails, power, test duration, seasonality, and analysis methods.
Analytics & ExperimentationOnsite - AmazonMediumApplied ScientistDesign an LLM quality validation system
This question evaluates an engineer's competency in ML system design for validating large language models, testing knowledge of evaluation metrics, validation scopes from internal numerics to final responses, system architecture for automated validation pipelines, and operational concerns within the ML System Design domain; it requires both conceptual architecture understanding and practical application-level thinking. It is commonly asked to assess the ability to reason about correctness, safety, regression risk, scalability, reproducibility, and monitoring trade-offs when deploying production-grade validation pipelines and to gauge familiarity with complementary evaluation methods and end-to-end data flows.
ML System DesignOnsite - AmazonHardData ScientistDesign an ML Model for Interview Recommendation Pipeline
Design an ML Model for Interview Recommendation Pipeline evaluates core ML concepts, assumptions, math intuition, training/evaluation trade-offs, and practical failure modes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Machine LearningOnsite - AmazonMediumApplied ScientistDesign an S3-like object storage service
This question evaluates understanding of distributed systems, object storage architecture, REST API design, multipart upload semantics, replication and durability strategies, failure recovery, and scalability concerns.
System DesignOnsite - AmazonHardSoftware EngineerDesign an online bookstore for browse and purchase
Design an online bookstore for browse and purchase 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 - AmazonHardData ScientistDesign an operations dashboard with justifications
This question evaluates a data scientist's ability to define precise operational metrics, justify visualization choices, design interactive drill-downs and alerting, and architect aggregation strategies for high-volume same-day delivery events.
Analytics & ExperimentationOnsite - AmazonMediumSoftware EngineerDesign and Implement a Shopping Cart Object Model for an Online Store
An object-oriented design exercise that asks you to model and implement a shopping cart for an online store, covering adding, updating and removing products and computing the total. It tests class boundaries, explicit edge-case policies, exact money handling and how cleanly the design extends to promotions.
Software Engineering FundamentalsOnsite - AmazonHardData ScientistDesign and analyze pricing-page A/B test
This question evaluates data-science competencies in online experiment design and analysis, including statistical power and sample-size estimation, variance-reduction methods, guardrail and SRM monitoring, randomization and contamination handling, sequential monitoring and stopping rules, heterogeneity/subgroup analysis, and result communication within the analytics & experimentation domain. It is commonly asked to assess practical application of statistical inference and experimental rigor in product and business contexts, primarily testing practical application while requiring conceptual understanding of underlying statistical principles and operational trade-offs.
Analytics & ExperimentationOnsite - AmazonHardSoftware EngineerDesign delayed job scheduler (LLD)
This question evaluates system design and distributed-systems competencies, including scheduling algorithms, durable persistence and recovery, concurrency control, delivery semantics, and operational concerns, and it belongs to the System Design category.
System DesignOnsite - AmazonHardSoftware EngineerDesign document-tag classes with concurrency safety
Design document-tag classes with concurrency safety 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 - AmazonHardData ScientistDesign end-to-end regression for energy demand
This question evaluates a candidate's ability to design and justify an end-to-end regression system for next-day site-level energy demand forecasting, testing competencies in time-series modeling, feature engineering, regularization, evaluation metrics and SLAs, production ML pipelines, monitoring, explainability, and data privacy.
Machine LearningOnsite - AmazonHardData ScientistDesign fraud detection across channels with unknowns
This question tests the ability to design an end-to-end fraud detection system that accounts for cold-start problems, cross-channel signals, and the trade-off between customer friction and loss mitigation.
Machine LearningOnsiteFraud DetectionAnomaly DetectionGraph Neural Networks - AmazonMediumSoftware EngineerDesign globally consistent metadata service
This question tests the ability to design a globally distributed metadata service that requires strict consistency for frequent read/write operations across multiple geographic regions.
System DesignOnsiteDistributed SystemsConsistencyScalability - AmazonMediumSoftware EngineerDesign multi-tenant ingestion and processing platform
This question tests the ability to design a multi-tenant data platform that ensures resource fairness, performance isolation, and cost attribution at scale.
System DesignOnsiteMulti-tenancyScalabilityDistributed Systems - AmazonMediumSoftware EngineerDesign object model for an elevator system
This question evaluates object-oriented design and system-architecture skills for modeling a multi-elevator control system, including class responsibilities, interactions, request flow, and scheduling policies.
Software Engineering FundamentalsOnsite - AmazonHardSoftware EngineerDesign ride-hailing pricing with fairness and pooling
This question evaluates system design and algorithmic skills related to real-time distributed pricing, API and data-flow architecture, carpooling logic, fairness constraints, and experimentation support.
System DesignOnsite - AmazonMediumSoftware EngineerDesign rolling-window top-K click tracker
Design rolling-window top-K click tracker evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - AmazonMediumData ScientistDesign student–course data models and SQL
This question evaluates data modeling, database design, and SQL proficiency—covering normalization, schema constraints, indexing, star-schema warehousing, slowly changing dimensions, partitioning strategies, and complex analytic queries—in the domain of relational databases and data warehousing (Data Manipulation/SQL).
Data Manipulation (SQL/Python)Onsite - AmazonHardApplied ScientistDesign systems for global request detection and labeling
This problem tests the architecture of a high-throughput streaming system capable of detecting anomalies in real-time, managing extreme class imbalance for labeling, and maintaining low-latency inference at a global scale.
ML System DesignOnsiteStreamingReal-time InferenceImbalanced Learning
Amazon