practice a little every day, paws crossed ♡
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 901–930 of 3640 results
- 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 - 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 custom iterator classes
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Implement custom iterator classes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerImplement custom iterators and interfaces
Implement custom iterators and interfaces 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 EngineerImplement filters and cursor pagination
This question evaluates a candidate's ability to design and implement cursor-based pagination, conjunctive per-field filtering, stable sort key selection, API surface design, and complexity analysis for a database-backed transaction query module.
Data Manipulation (SQL/Python)Onsite - CoinbaseMediumSoftware EngineerImplement iterators and write tests in Java
Implement iterators and write tests in Java 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 - CoinbaseMediumData ScientistIncrement Digit Array
This question tests the ability to handle array-based arithmetic and carry propagation logic, specifically addressing edge cases like array resizing.
Coding & AlgorithmsOnsiteArraysMathSimulation - CoinbaseMediumSoftware EngineerMaintain the Kth-Highest User Score with Updates and Removals
This problem tests your ability to maintain a dynamic set of scores and efficiently retrieve the k-th highest element using balanced data structures or ordered collections.
Coding & AlgorithmsOnsiteData StructuresBalanced BSTHash Map - CoinbaseHardSoftware EngineerMaximize block fee with transaction selection
This question evaluates algorithmic optimization and dependency-aware selection skills, focusing on resource-constrained selection (knapsack-like trade-offs) and graph-based dependency reasoning within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerMaximize profit with transaction fee
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Maximize profit with transaction fee states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerMaximize profit with transaction fees
This question evaluates algorithm design skills, specifically understanding of dynamic programming and greedy strategies for optimizing profit under transaction fees, along with stateful decision-making and handling cost constraints.
Coding & AlgorithmsOnsite - CoinbaseMediumSoftware EngineerParse logs and generate NFT attributes
This problem tests your ability to parse structured log strings, group events by metadata, and perform weighted sampling across combinations of attributes.
Coding & AlgorithmsOnsiteParsingHashingProbability - CoinbaseHardFrontend EngineerPresent a Previous Project Deep Dive
This question evaluates technical depth, architectural reasoning, leadership, and cross-team collaboration skills within frontend engineering, focusing on system/frontend architecture, tradeoff analysis, incident management, and measurable impact.
Behavioral & LeadershipOnsite - CoinbaseMediumSoftware EngineerResolve a Disagreement in Code Review
This question tests your ability to navigate technical conflict, exercise professional judgment, and demonstrate collaborative communication skills during a pull request review.
Behavioral & LeadershipOnsiteCommunicationCode ReviewConflict Resolution - CoinbaseMediumSoftware EngineerSchedule Fixed-Order Tasks with a Cooldown
Calculate the total days required to run a sequence of tasks in a strict, fixed order where identical tasks must be separated by a specified cooldown period.
Coding & AlgorithmsOnsiteArrayHash TableGreedy - CoinbaseMediumSoftware EngineerSelect transactions to maximize fees under size
This problem tests your ability to solve a variation of the 0/1 Knapsack problem where items have both a cost (size) and a value (fee).
Coding & AlgorithmsOnsiteDynamic ProgrammingOptimizationAlgorithms - CoinbaseMediumMachine Learning EngineerWrite SQL to rank top products per category
This question evaluates SQL proficiency in aggregation, time-based filtering, joining transactional and reference tables, and ranking/windowing techniques to compute and deterministically order product revenue with tie-breaking by product_id.
Coding & AlgorithmsOnsite - CoinbaseMediumData ScientistWrite SQL: sum values ≤ each row’s value
This question evaluates proficiency in SQL aggregation, query optimization, and handling duplicate values when computing cumulative sums across rows. It is commonly asked to assess practical ability in the Data Manipulation (SQL/Python) domain to design scalable, efficient queries and demonstrates a focus on practical application of query-design and optimization rather than purely conceptual theory.
Data Manipulation (SQL/Python)Onsite - ConfluentMediumSoftware EngineerCheck Whether a Partially Filled 9x9 Sudoku Board Is Valid
A coding problem that asks whether a partially filled 9x9 Sudoku board is consistent, meaning no row, column or 3x3 box repeats a digit among its filled cells. It tests careful bookkeeping of row, column and box membership without attempting to solve the puzzle.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerDesign RSS Feed and Temporary Mail
This question tests the ability to design a dual-purpose system that handles high-throughput asynchronous feed ingestion and transient, short-lived email alias management.
System DesignOnsiteDistributed SystemsCachingMessage Queues - ConfluentMediumSoftware EngineerDesign a News Feed and Mail Service
This question evaluates a candidate's proficiency in large-scale system design, including distributed ingestion and deduplication, content ranking, API design choices (REST versus RPC), pagination and caching strategies, and techniques for generating and ensuring uniqueness of human-looking disposable email addresses.
System DesignOnsite - ConfluentMediumSoftware EngineerDesign a Podcast Publishing System That Delivers New Episodes to Followers
A system design question about a podcast platform where creators publish episodes and followers see them in a feed. It covers the upload and processing path for audio, building each listener's feed of new episodes, and serving shows whose audiences range from a handful of listeners to millions.
System DesignOnsite
Coinbase
Confluent