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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 2461–2490 of 9403 results
- CoinbaseMediumData ScientistDetect sequence rule and repair anomaly
This question evaluates a candidate's skill in sequence pattern recognition, algorithm design, complexity analysis, and robust integer arithmetic by requiring inference among arithmetic, alternating-difference, geometric, and Fibonacci-plus-constant models while tolerating at most one corrupted term under O(n) time and O(1) extra space constraints.
Coding & AlgorithmsHR 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 - CoinbaseMediumSoftware EngineerDiscuss complex project and multi-approach example
A Coinbase onsite behavioral pairing that asks you to walk through the most complex project you led end-to-end — its complexity, decomposition, risks, your specific contributions, and measured outcomes — and then to show a problem you attacked with several different methods. The solution gives a STAR+L structure, a reusable template, and full sample answers for both prompts with the trade-off reasoning interviewers actually score. It also covers the common failure modes: vague impact, hiding behind "we," and presenting only one approach.
Behavioral & LeadershipOnsite - CoinbaseMediumSoftware EngineerDiscuss your proudest project
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Discuss your proudest project states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipOnsite - 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 - CoinbaseMediumBackend EngineerEvolve Cursor Pagination Without Breaking Clients
This problem tests the ability to design stable, deterministic cursor-based pagination systems that handle non-unique sort keys and schema evolution without breaking backward compatibility.
Software Engineering FundamentalsOnsiteAPI DesignPaginationSQL - CoinbaseMediumSoftware EngineerExplain Your Role in a Production Incident
This question assesses a candidate's ability to navigate high-pressure production incidents, focusing on structured problem-solving, cross-functional communication, and technical ownership.
Behavioral & LeadershipOnsiteBehavioralIncident ManagementOwnership - CoinbaseMediumData ScientistExplain handling pressure to bend rules
This question evaluates a candidate's competency in ethical decision-making, risk assessment, regulatory compliance (including data governance and payroll/immigration constraints), stakeholder influence, and cross-functional communication under pressure.
Behavioral & LeadershipHR 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 - CoinbaseHardMachine Learning EngineerExplain precision/recall and compute NN output
This question tests the ability to calculate classification performance metrics, explain ensemble model dynamics, and perform manual forward propagation through a small neural network architecture.
Machine LearningOnline AssessmentClassificationNeural NetworksEnsemble Methods - 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 - CoinbaseHardSoftware EngineerGenerate NFT metadata and ensure uniqueness
This question evaluates understanding of combinatorics, deterministic pseudo-random generation, and efficient enumeration for producing unique NFT metadata, measuring competency in algorithm design, state-space management, and handling large-scale outputs.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerGenerate Weighted Random NFTs with Updates
This question evaluates understanding of weighted random sampling, efficient data structures for maintaining and updating prefix sums, probabilistic reasoning about sampling distributions, and reproducible testing of randomized algorithms within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerGenerate constrained NFT metadata
Generate constrained NFT metadata 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 - CoinbaseMediumSoftware EngineerHandle recruiter transparency and background checks
Handle recruiter transparency and background checks 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 & LeadershipOnsite - CoinbaseMediumSoftware EngineerImplement Composable Range Iterators
This question evaluates understanding of iterator design, lazy evaluation, composable higher-order combinators (map, filter, zip, take, drop, chain), edge-case handling for forward/backward and negative-step ranges, overflow-safe termination, peekable semantics, iterator invalidation rules, and writing boundary-focused unit tests.
Coding & AlgorithmsOnsite - CoinbaseHardSoftware EngineerImplement Game Physics and Block Mining
This question evaluates implementation skills in deterministic game physics (discrete position and velocity updates with boundary and edge-case handling) alongside dependency-aware greedy selection for block construction, testing graph dependency resolution, greedy heuristics, and complexity analysis in the Coding & Algorithms domain, and is commonly asked to verify correctness under constraints, handling of boundary conditions, and trade-offs between optimality and performance. Level of abstraction spans both conceptual understanding (kinematic update rules, cycle detection, fee/size ratio reasoning) and practical application (implementing the tick update and returning a topologically ordered block while considering caching and scalability for large mempools).
Coding & AlgorithmsOnsite - CoinbaseMediumData ScientistImplement Plus One
This question evaluates array manipulation and numeric carry propagation skills, along with the ability to reason about time and space complexity when performing arithmetic on digit lists.
Coding & AlgorithmsOnsite - CoinbaseHardSoftware EngineerImplement a Coin-Constrained Jump Strategy
Design a pathfinding algorithm to reach a target coordinate in the minimum number of jumps subject to physics-based velocity adjustments, obstacle avoidance, and a non-negative coin balance constraint.
Coding & AlgorithmsOnline AssessmentBFSDynamic ProgrammingGraph Search - 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 - CoinbaseHardFrontend EngineerImplement a Reusable Dropdown Component
This question evaluates skills in reusable frontend component design, including API design, state management (controlled vs uncontrolled), event handling, keyboard navigation, and accessibility (roles, focus behavior, and ARIA) for production-ready UI components.
Software Engineering FundamentalsOnsite - CoinbaseMediumSoftware EngineerImplement a Simple Banking Ledger
This question evaluates competence in designing an efficient, stateful ledger API and associated data structures, emphasizing correctness under invalid inputs, performance at scale, integer overflow handling, unit testing for edge cases, and transactional (atomic batch) behavior.
Coding & AlgorithmsOnsite - CoinbaseMediumBackend EngineerImplement a Stateful Trading Order Manager
This problem tests your ability to design a stateful system using hash-based sharding, efficient indexing, and robust state machine transitions for high-frequency financial orders.
Coding & AlgorithmsOnsiteHash TablesSystem DesignState Machines - 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 a versioned recipe management system
This question evaluates data-structure design and state-management competencies, covering CRUD, case-insensitive search/sort semantics, user management, and versioning/rollback for an in-memory Recipe Management System in the Coding & Algorithms domain.
Coding & AlgorithmsOnline Assessment - 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
Coinbase