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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 1201–1230 of 4616 results
- CloudKitchensMediumSoftware EngineerImplement menu parser and serializer
This question evaluates proficiency in text parsing, hierarchical data modeling, tree construction and serialization, string manipulation, and algorithmic complexity (linear time/space).
Coding & AlgorithmsTechnical Screen - CloudTrucksMediumData ScientistCalculate Average Rate and Cumulative Jobs by State
This question evaluates competency in relational data manipulation and analytical SQL concepts—including joins, aggregation with DISTINCT counts, per-date averaging, rolling cumulative counts, and handling numeric edge cases—within the Data Manipulation (SQL/Python) domain for a data scientist role.
Data Manipulation (SQL/Python)Technical Screen - CloudflareMediumSoftware EngineerDesign an encrypted key-value store with login
This question evaluates a candidate's understanding of secure authentication, key management, and applied cryptography for encrypting data at rest within a user-scoped key–value store.
Software Engineering FundamentalsTechnical Screen - CognitivMediumMachine Learning EngineerDesign a Real-Time Feature Store
This question evaluates a candidate's ability to design real-time feature store architectures, encompassing competencies in low-latency serving, point-in-time correctness for offline training, streaming ingestion, consistency between online and offline features, handling backfills and late events, and scalable monitoring of data quality and reliability. It is commonly asked to assess systems-design and data-engineering judgment for production-grade ML infrastructure, falls under the ML system design and data engineering domain, and tests both conceptual understanding of trade-offs (consistency, latency) and practical application skills for APIs, storage, and operational design.
ML System DesignTechnical Screen - CognitivMediumMachine Learning EngineerMaintain a Streaming Median
This question evaluates understanding of streaming algorithms and dynamic data structures for maintaining order statistics, along with analysis of time complexity and memory trade-offs.
Coding & AlgorithmsTechnical Screen - CognitivHardSoftware EngineerReason About Duplicate Data and Scaling in Spark
This problem tests the ability to design an idempotent, scalable data deduplication pipeline in Apache Spark while considering distributed systems constraints like data skew and state management.
Software Engineering FundamentalsTechnical ScreenApache SparkDistributed SystemsData Engineering - CohereMediumSoftware EngineerAnswer Enterprise Questions Across Internal and External Sources
Design enterprise AI question answering across internal and external sources with permission-aware retrieval, entity mapping, evidence-grounded synthesis, and freshness controls.
System DesignTechnical Screen - CoinbaseEasyData ScientistCalculate Expected Users Adopting Wallet Feature
This interview question evaluates statistical assumptions, formulas, estimation strategy, uncertainty, edge cases, and interpretation in a realistic interview setting. A strong answer for Calculate Expected Users Adopting Wallet Feature states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Statistics & MathTechnical Screen - CoinbaseEasyData ScientistCalculate Expected Users Linking Coinbase Wallets
Coinbase probability question covering Bernoulli indicators, expected wallet links, complement rule for at least one success, and conditional probability for two users linking wallets.
Statistics & MathTechnical Screen - CoinbaseMediumSoftware EngineerCount users over n connections
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Count users over n connections states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - CoinbaseMediumSoftware EngineerDescribe cross-team collaboration on past projects
This question evaluates cross-team collaboration, stakeholder communication, conflict resolution, ownership, and coordination competencies within software delivery.
Behavioral & LeadershipTechnical Screen - CoinbaseMediumSoftware EngineerDesign a blob storage system for lunar environment
This question evaluates system design and distributed storage competencies, focusing on durability, replication, metadata management, consistency, and trade-offs under resource-constrained, high-latency conditions; it is in the System Design category and tests knowledge across distributed systems, storage architecture, and networking.
System DesignTechnical Screen - CoinbaseMediumSoftware EngineerDesign a food delivery system
This problem tests your ability to design a distributed, real-time logistics platform, focusing on high-concurrency order placement, real-time courier tracking, and transactional integrity during payment and dispatch.
System DesignTechnical ScreenScalabilityReal-timeGeospatial - CoinbaseMediumSoftware EngineerDesign crypto trading order control API
This question evaluates understanding of state management and finite-state machines, API design for lifecycle control, and implementation of in-memory data structures and transition validation in the Coding & Algorithms category.
Coding & AlgorithmsTechnical Screen - CoinbaseHardData ScientistDiagnose a 20% retail revenue drop
This question evaluates a data scientist's ability in revenue decomposition, diagnostic analytics, causal inference, and experimentation design, covering traffic×CVR×AOV breakdowns, post-purchase deductions, stockout impacts, rapid falsifiable checks, and difference-in-differences-style attribution.
Analytics & ExperimentationTechnical Screen - CoinbaseMediumData ScientistDiagnose a Sudden Revenue Decline: Analyses, Metrics, and Root-Cause Tests
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 Diagnose a Sudden Revenue Decline: Analyses, Metrics, and Root-Cause Tests states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - CoinbaseMediumData ScientistEstimate Super Bowl QR Code Scan Rate Using Historical Data
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 Estimate Super Bowl QR Code Scan Rate Using Historical Data states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - CoinbaseMediumData ScientistEstimate Viewer Engagement with Super Bowl QR Code Promo
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 Estimate Viewer Engagement with Super Bowl QR Code Promo states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen - CoinbaseMediumSoftware EngineerExplain motivation, UX quality, and change handling
Explain motivation, UX quality, and change handling evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - CoinbaseHardSoftware EngineerExtend a Banking Interface with Scheduled Payments and Account Merges
Implement an in-memory transactional banking system supporting scheduled payments, deterministic tick-based execution, idempotency, and account merging with balance consolidation and redirect tracking.
Software Engineering FundamentalsTechnical Screensystem-designdata-structuresconcurrency - CoinbaseMediumSoftware EngineerFee-Maximizing Block Assembly from a Mempool with Child-Pays-For-Parent
A coding question on assembling a cryptocurrency block from a very large mempool: pick transactions that maximize fees within a fixed block size using a fast heuristic, then extend the selection to parent links and Child-Pays-For-Parent incentives. An optional part asks for the minimum fee a child must pay to pull its parent into the next block.
Software Engineering FundamentalsTechnical Screen - CoinbaseMediumSoftware EngineerImplement a Flappy Bird Jump Agent
This problem tests your ability to design a simple heuristic-based agent that navigates a 2D environment by calculating clearance intervals and applying physics-based jump logic.
Coding & AlgorithmsTechnical ScreenSimulationHeuristicsPhysics - CoinbaseMediumSoftware EngineerImplement a blog feed with fetching and state
This problem tests your ability to handle asynchronous data fetching, state synchronization, and UI interactions in React, specifically managing a list of blog posts with optimistic updates and sorting.
Software Engineering FundamentalsTechnical ScreenReactFrontendAsync - CoinbaseMediumSoftware EngineerImplement bank account with cashback
This question evaluates implementation skills in sequential operation processing, integer arithmetic, control flow, edge-case handling, and overflow awareness within algorithmic constraints.
Coding & AlgorithmsTechnical Screen - CoinbaseMediumSoftware EngineerImplement bank balance operations
This question evaluates object-oriented programming, state management, input validation, and arithmetic correctness when implementing account operations and maintaining transactional invariants.
Coding & AlgorithmsTechnical Screen - CoinbaseMediumSoftware EngineerImplement basic pagination for a list
This question evaluates a candidate's competence in array indexing, boundary-condition handling, and simple pagination logic, focusing on correct subarray extraction and off-by-one considerations within given size constraints.
Coding & AlgorithmsTechnical Screen - CoinbaseMediumSoftware EngineerImplement cursor-based query pagination
This question evaluates understanding of cursor-based pagination, deterministic ordering with tie-breakers, cursor encoding, and in-memory data-structure management for efficient filtered queries.
Coding & AlgorithmsTechnical Screen - CoinbaseMediumSoftware EngineerImplement debounced async autocomplete input
Implement debounced async autocomplete input evaluates requirements, assumptions, structured reasoning, trade-offs, and verification in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsTechnical Screen - CoinbaseMediumSoftware EngineerImplement debounced autocomplete component
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Implement debounced autocomplete component states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsTechnical Screen - CoinbaseMediumData ScientistInvestigate Anomalies in Coinbase Wallet Engagement Metrics
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 Investigate Anomalies in Coinbase Wallet Engagement Metrics states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationTechnical Screen
Cloudflare
Cohere
Coinbase