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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
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- 11
- Topics
- 8
- Languages
Showing 3091–3120 of 3640 results
- SheinMediumSoftware EngineerSolve array modulo and parentheses tasks
This question evaluates proficiency in modular arithmetic and subarray-sum reasoning for remainder counting, together with string manipulation and parentheses-balancing competencies, testing algorithmic problem-solving, correctness justification, and implementation skills in the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - ShopifyMediumData ScientistAnalyze Causes of November and June Shopify Traffic Spikes
This interview question evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer for Analyze Causes of November and June Shopify Traffic Spikes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationOnsite - ShopifyMediumData ScientistAssess Candidate's Remote Collaboration and Technical Proficiency
Evaluates remote cross-functional collaboration and technical proficiency for a data-science role. Strong answers cover challenging projects, stakeholder rituals, async artifacts, tool stack, reproducibility, and quantified impact.
Behavioral & LeadershipOnsite - ShopifyMediumMachine Learning EngineerBuild model to predict package delivery time
This question evaluates a candidate's competence in end-to-end machine learning system design for time-to-event forecasting, covering prediction target definition and timing, feature engineering and model selection, handling missing or delayed signals and data leakage, uncertainty quantification, and production monitoring and retraining.
Machine LearningOnsite - ShopifyMediumData ScientistCalculate Jaccard Similarity Score for Two String Lists
This question evaluates understanding of similarity metrics and competency in comparing string collections, reflecting knowledge of set-theoretic concepts and manipulation of collection data structures used in data processing.
Coding & AlgorithmsOnsite - ShopifyHardMachine Learning EngineerCollect labels without existing data
This question evaluates a machine learning engineer's competency in label definition and leakage prevention, instrumentation and logging design, programmatic and human-in-the-loop labeling pipelines, experimental approaches for eliciting outcomes, bias mitigation, and continuous label quality monitoring.
Analytics & ExperimentationOnsite - ShopifyMediumMachine Learning EngineerDescribe an end-to-end ML project
This question evaluates leadership and technical competencies in end-to-end machine learning project execution—specifically project management, cross-functional stakeholder coordination, ML system design, data engineering, modeling, evaluation, and production monitoring; it sits in the Behavioral & Leadership category and the domain of machine learning systems and product analytics, testing practical application of these skills. It is commonly asked to determine a candidate's ability to translate business objectives into measurable ML solutions, reason about trade-offs across metrics, data, modeling and infrastructure, and demonstrate both conceptual understanding and hands-on operationalization.
Behavioral & LeadershipOnsite - ShopifyMediumMachine Learning EngineerDesign Personalized Product Feeds
This question evaluates a candidate's ability to design end-to-end machine learning systems for personalized product recommendation, assessing competencies in data collection, candidate generation, feature pipelines, model training, online serving, and re-ranking.
ML System DesignOnsite - ShopifyMediumSoftware EngineerDesign a Product Photography Upload Service
Design a product-photography workflow from shoot creation and direct upload through processing, merchant review, acceptance, and reshoots. Cover scoped upload authorization, authoritative metadata, idempotent state transitions, stale completion events, notifications, retention, and publication safety.
System DesignOnsite - ShopifyHardMachine Learning EngineerDesign a baseline loan recommendation system
This question evaluates understanding of ML-driven recommendation and credit-risk systems, including skills in personalization, feature design, risk calibration, fairness and regulatory compliance, explainability, and operational monitoring.
ML System DesignOnsite - ShopifyHardMachine Learning EngineerDesign a hierarchical multi-label classifier
This question evaluates a candidate's competency in designing production-grade hierarchical multi-label classification systems, covering taxonomy normalization, label dependency modeling, loss and decoding strategies, class imbalance handling, evaluation metrics, data labeling at scale, and operational constraints such as latency, model size, and monitoring. Commonly asked in the ML System Design domain to assess both conceptual understanding of hierarchical label structures and practical application-level trade-offs in architecture, training, deployment, and maintenance.
ML System DesignOnsite - ShopifyHardSoftware EngineerDesign a rare-book lending and returns system
Design a rare-book lending and returns 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 DesignOnsite - ShopifyMediumMachine Learning EngineerDesign search autocomplete ML system
This question evaluates an engineer's ability to design an ML-powered search autocomplete system, testing competencies in candidate generation versus ranking architectures, data sourcing and labeling, feature and model selection (including personalization and context), offline training and online serving, experimentation and monitoring, and safety and abuse mitigation within information retrieval. Commonly asked to assess how applicants balance production concerns such as latency, relevance, scalability, cold-start handling, and feedback-loop mitigation, it sits in the ML system design domain and emphasizes practical, applied engineering trade-offs rather than purely conceptual theory.
ML System DesignOnsite - ShopifyMediumData ScientistDetermine Growth of Pirated Theme Installations Over Years
This question evaluates proficiency in SQL-based data manipulation and analytics, focusing on computing time-based cohort percentages and conducting year-over-year trend analysis of merchant behavior.
Data Manipulation (SQL/Python)Onsite - ShopifyMediumData ScientistDiagnose Weekly Session Conversion Anomalies
This question evaluates proficiency in time-series anomaly detection, conversion-rate analysis, data quality handling (especially parsing and validating week labels), segmentation by shop type and session-duration buckets, and causal reasoning about traffic composition effects.
Analytics & ExperimentationOnsite - ShopifyMediumSoftware EngineerEngineering Manager Career Story: Team Impact, Quality Bar and Performance Management
A behavioral round for engineering managers that asks you to tell your management story through concrete examples. It tests the impact you drove through teams, how you kept the engineering quality bar high under pressure, how you handled underperformance, and how you grew people into larger roles.
Behavioral & LeadershipOnsite - ShopifyMediumMachine Learning EngineerImplement URL Shortening Codec
This question evaluates understanding of hashing, encoding, state management, and collision-handling strategies for creating a consistent mapping between long and short URLs, testing competencies in data structures, algorithms, and simple system design within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - ShopifyMediumSoftware EngineerImplement an In-Memory File System
Implement an in-memory file system with absolute and relative path resolution, sorted listing, directory changes, creation, and removal. Enforce deterministic error codes, atomic validation, recursive deletion rules, and protection for the current directory and its ancestors.
Coding & AlgorithmsOnsite - ShopifyMediumMachine Learning EngineerImplement an interactive CLI class with tests
This question evaluates object-oriented design, command-line interface implementation, persistent state management, input validation and error logging, extensibility for new commands, comprehensive unit testing, and continuous integration configuration.
Coding & AlgorithmsOnsite - ShopifyMediumData ScientistMeasure Shopify App Store Success
This question evaluates a data scientist's competency in product-metrics design for a multi-sided app marketplace, including defining a north-star metric, per-side success and guardrail metrics, required dataset schemas and join keys, and criteria for evaluating ranking/search/recommendation experiments.
Analytics & ExperimentationOnsite - ShopifyMediumMachine Learning EngineerModel Product Ranking
This question evaluates understanding of end-to-end machine learning ranking systems, including label definition, feature engineering, model selection, training strategies, and offline/online evaluation.
Machine LearningOnsite - ShopifyMediumSoftware EngineerTechnical Deep Dive: Present a System You Built as a Design Retrospective
A senior engineering interview round in which you present a system you designed or led, using a diagram prepared in advance, and then defend it under questioning. It tests how you frame the problem and your ownership, explain key decisions and their alternatives, discuss failures honestly, and go deep on any component.
System DesignOnsite - SierraMediumSoftware EngineerDesign an LLM-Powered Customer Service Chat System with Robust Failure Handling
A system design interview for a customer-service chat system whose replies come from an external LLM provider. It walks through the end-to-end happy path and publish/subscribe message delivery, then focuses on error handling when the provider partially fails or the network drops, on both the server and the client.
System DesignOnsite - SigmacomputingMediumSoftware EngineerEvaluate a Formula AST with Variables
This problem tests tree traversal techniques, recursive evaluation, and the implementation of short-circuit logic in expression trees containing variables.
Coding & AlgorithmsOnsiteTreesRecursionAST - SnapchatHardMachine Learning EngineerCompare Batch Normalization and Layer Normalization
Compare batch and layer normalization by their axes, learned parameters, running statistics, batch-size effects, and training-to-inference debugging.
Machine LearningOnsite - SnapchatHardSoftware EngineerCompare WebSocket, SSE, and long polling
This question tests a software engineer's depth in web networking fundamentals, covering real-time communication protocols and the OSI and TCP/IP models. It assesses practical knowledge of WebSocket, SSE, and long polling trade-offs, as well as understanding of how modern transport protocols like QUIC differ from TCP in multiplexing, handshake latency, and connection migration.
Software Engineering FundamentalsOnsite - SnapchatMediumData ScientistCompute CTR and metrics with pandas
This question evaluates proficiency in time-series and event-level data manipulation with pandas, including CTR computation, event denoising and deduplication, sessionization, cohort analysis, temporal joins, and performance-aware vectorized operations within the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Onsite - SnapchatMediumData ScientistCompute User Retention and Analyze Event Data
This question evaluates a candidate's ability to perform SQL and Python data manipulation for event analytics, including cohort retention, aggregation of distinct purchasing users, median-of-daily-events calculations, and hourly time-series grouping.
Data Manipulation (SQL/Python)Onsite - SnapchatMediumSoftware EngineerCompute islands in a binary grid
This question evaluates a candidate's competency in modeling grids as graphs, detecting connected components, applying graph traversal algorithms (DFS/BFS) and disjoint-set (Union-Find) data structures, and analyzing algorithmic time and space complexity.
Coding & AlgorithmsOnsite - SnapchatHardSoftware EngineerCompute longest increasing path in matrix
This question evaluates algorithmic problem-solving skills in graph traversal and dynamic programming on matrices, measuring understanding of state representation and performance trade-offs in grid-based searches within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite
Shopify
Sierra
Snapchat