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Data 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 1–26 of 26 results

  • AppleMediumData Engineer
    Design TikTok Data Engineering Systems

    This problem tests the ability to design an end-to-end data pipeline for high-throughput mobile app event logging, focusing on ingestion, transformation, and storage optimization.

    System DesignTechnical ScreenData PipelinesDistributed SystemsOLAP
  • BasetenMediumData Engineer
    Design a Data Pipeline for Messy Pod Alerts and Bad Pod Detection

    Prepare for a Baseten system design interview about design a data pipeline for messy pod alerts and bad pod detection. This question focuses on requirements, architecture, trade-offs, reliability, and follow-up discussion areas.

    System DesignTechnical Screen
  • ByteDanceMediumData Engineer
    Design 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
  • Capital OneMediumData Engineer
    Evaluate credit-limit increase profitability

    This question evaluates a data engineer's competency in business analytics, unit-economics P&L modeling, risk-versus-revenue trade-off analysis, and experiment-driven evaluation of credit product changes.

    System DesignTechnical Screen
  • DiscordHardData Engineer
    Design Video Call Analytics Tables

    This question evaluates data modeling and analytics competencies including event schema design, dimensional modeling (facts and dimensions), ETL/cleaning and deduplication, and time-windowed SQL aggregation.

    System DesignOnsite
  • DisneyEasyData Engineer
    Data Pipeline Design for Cloud and Hybrid On-Prem Environments on AWS and Azure

    A senior data engineering design question: build a data pipeline from operational sources to analytics on one cloud, then rework it for a hybrid on-premises and cloud environment and for both AWS and Azure. It tests tool selection and trade-offs, ingestion and storage design, data quality, security and portability.

    System DesignOnsite
  • DisneyMediumData Engineer
    Design a clickstream ingestion and aggregation pipeline for billions of events per day

    Design an end-to-end clickstream pipeline that ingests roughly one billion telemetry events per day from web, mobile, and TV clients and serves both near-real-time dashboards and accurate finalized daily aggregates without lagging. The question covers staged architecture and back-of-envelope sizing, a durable partitioned log for back-pressure, event-time windowing with watermarks and allowed lateness, late-arriving data and the provisional-to-finalized lifecycle, exactly-once deduplication in Flink versus Spark Structured Streaming, autoscaling on consumer lag, hot-partition key skew, high-cardinality DAU/MAU with HyperLogLog, and reprocessing after a logic bug. A common Disney data engineer online assessment system design question.

    System DesignOnline Assessment
  • FigureaiMediumData Engineer
    Build a Firmware Data Quality and Release-Feedback Framework

    This question tests the ability to design an end-to-end data pipeline architecture that ensures high-fidelity telemetry collection, automated quality validation, and safe release orchestration for embedded firmware devices.

    System DesignTechnical ScreenData EngineeringFirmwareObservability
  • FigureaiMediumData Engineer
    Design a Telemetry Platform Ingesting Two Gigabytes per Second

    This question tests your ability to design a high-throughput, fault-tolerant telemetry ingestion pipeline capable of handling high-velocity data streams from distributed robotic systems.

    System DesignTechnical ScreenData EngineeringScalabilityDistributed Systems
  • Jain GlobalMediumData Engineer
    Design an Incremental Rolling-Metrics Data Pipeline

    Design an incremental batch data pipeline to compute multi-horizon rolling financial metrics over daily ticker observations, handling bounded historical restatements, atomic publication, and data reconciliation.

    System DesignTechnical ScreenData EngineeringData PipelinesFinancial Data
  • Jain GlobalMediumData Engineer
    Design and Debug a Point-in-Time Backtest Data Pipeline

    This problem tests the ability to architect a robust financial data pipeline that ensures point-in-time accuracy and reproducible research.

    System DesignTechnical ScreenData EngineeringFinancial DataBacktesting
  • Jain GlobalMediumData Engineer
    Model Effective-Dated Compliance Restrictions for Securities

    This question tests the ability to design a time-series database schema capable of handling bitemporal data, identifier changes, and overlapping compliance restrictions.

    System DesignTechnical ScreenData ModelingTime-SeriesBitemporal
  • MetaMediumData Engineer
    Define metrics and data model for product features

    This problem evaluates your ability to translate product goals into actionable metrics and design a scalable, reliable data schema to support those metrics.

    System DesignTechnical ScreenData ModelingProduct AnalyticsMetrics
  • MetaHardData Engineer
    Design batch and streaming ETL architecture

    Design batch and streaming ETL 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
  • MetaHardData Engineer
    Design tables for event-driven metrics

    This question evaluates relational data modeling and data engineering competencies for high-volume event analytics, including schema design, partitioning and clustering strategies, duplicate and late-arriving event handling, and normalization versus denormalization trade-offs.

    System DesignTechnical Screen
  • MetaHardData Engineer
    Evaluate impact of short videos in feed

    This question evaluates competency in metrics definition, causal experimentation, product analytics, and feed system behavior within the System Design and Data Engineering domain.

    System DesignOnsite
  • NVIDIAMediumData Engineer
    Design a GPU Telemetry Collection and Analytics Platform

    Prepare for a NVIDIA system design interview about design a gpu telemetry collection and analytics platform. This question focuses on requirements, architecture, trade-offs, reliability, and follow-up discussion areas.

    System DesignTechnical Screen
  • NetflixHardData Engineer
    Design config rollout and click aggregation

    This problem tests your ability to design a global configuration distribution system combined with a high-throughput event processing pipeline to monitor rollout health.

    System DesignOnsiteDistributed SystemsReal-time AnalyticsEvent Streaming
  • NextdoorHardData Engineer
    Design KPI dashboard tables: retention, weekly rollups, timezone

    This Nextdoor data engineer system design screen asks you to design the analytical data model and incremental ETL behind a fast, large-scale KPI dashboard for a photo-sharing app. It covers derived aggregate table design (grain, keys, partitioning), DAU/new-user/new-photo and follower-distribution metrics, 7-day deltas, then extends to week-1 cohort retention, weekly rollups, and switching the reporting timezone. The focus is correctness, performance at scale, and maintainability with timezone handled as a reporting parameter.

    System DesignTechnical Screen
  • Otter.AiMediumData Engineer
    Defend a Data Pipeline Architecture and Its Trade-offs

    Prepare to defend a production data pipeline you genuinely built or changed. The prompt tests how you connect requirements to architecture, compare alternatives, explain replay and backfills, diagnose a hard failure, quantify outcomes, and reflect on ownership and trade-offs.

    System DesignTechnical Screen
  • PatreonEasyData Engineer
    Design a Data Processing System for JSON User Records: Batch vs Streaming Input

    Design a data processing system for JSON user records that contain names, addresses and payment methods, and explain how the design changes when the upstream source delivers data in batches versus as a continuous stream. It tests pipeline architecture, idempotent loading, ordering and late data, and the handling of sensitive fields.

    System DesignTechnical Screen
  • Point72HardData Engineer
    Design Data Quality and Observability Pipeline

    This question evaluates proficiency in designing production data orchestration, data quality validation, and observability frameworks for both batch and streaming pipelines, covering dependency management, schema and integrity checks, and operational handling of anomalous records.

    System DesignTechnical Screen
  • ShopifyMediumData Engineer
    Choose Between Batch and Streaming for a Data Pipeline

    Work through a data-platform design that must support fast operational metrics and reproducible daily reporting. Compare batch, streaming, and hybrid choices while addressing late events, deduplication, replay, backfills, governance, and recovery.

    System DesignTechnical Screen
  • TikTokHardData Engineer
    Design a Warehouse for Key Metrics

    This question evaluates a data engineer's skills in dimensional modeling, data warehousing, and analytics infrastructure, covering facts and dimensions, grain definition, surrogate keys, partitioning and clustering strategies, and operational concerns like deduplication, late-arriving events, null/anonymous users, and slowly changing dimensions.

    System DesignTechnical Screen
  • ZooxMediumData Engineer
    Design teleoperations data models and pipelines

    This question evaluates competency in data modeling, real-time and batch pipeline architecture, telemetry ingestion, metrics design, and operational monitoring for teleoperations and autonomous vehicle stability.

    System DesignOnsite
  • xAIMediumData Engineer
    Build a One-Pass Data Cleaning Pipeline

    This problem tests your ability to design a memory-efficient, scalable data streaming pipeline that processes raw web-scraped documents into a high-quality dataset for model pretraining.

    System DesignTechnical ScreenData EngineeringStreamingData Cleaning