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Software Engineering Fundamentals 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 301–330 of 1208 results
- Citadel SecuritiesMediumSoftware EngineerDefine a Reliable Trade-Reconciliation Library Contract
Define trade-reconciliation contracts and OOP boundaries with exact values, timestamp tolerance, partial-fill questions, deterministic policy ownership, and traceable breaks.
Software Engineering FundamentalsTechnical Screen - Citadel SecuritiesMediumSoftware EngineerDesign a Top-Ten Trade Query with Exact Amounts
Design a top-ten trade query around an explicit ranking contract, exact monetary aggregation, bounded heaps, timestamp boundaries, and mutable-score streaming tradeoffs.
Software Engineering FundamentalsTechnical Screen - Citadel SecuritiesMediumSoftware EngineerDetect Currency Arbitrage and Return a Profitable Conversion Cycle
Given a list of currency conversion rates, determine whether an arbitrage opportunity exists and return a sequence of conversions that ends in the starting currency with more money than it began with. Tests graph modeling, cycle detection, reconstruction of the profitable sequence, and handling of floating-point precision.
Software Engineering FundamentalsOnsite - Citadel SecuritiesMediumSoftware EngineerThread-Safe Producer-Consumer Queue: Mutex, Then Spin Lock, Then Lock-Free
Implement a thread-safe producer-consumer queue in C++, first with a mutex, then with a spin lock, then as a lock-free design with explicit memory ordering. Tests the C++ memory model, contention and cache effects, blocking versus spinning, and where memory is allocated on the hot path.
Software Engineering FundamentalsOnsite - 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 - CloudflareEasySoftware EngineerExplain debugging methodology for production issues
This question evaluates a candidate's troubleshooting and incident-response skills, including root-cause analysis, systems-level reasoning, and prioritization under production constraints.
Software Engineering FundamentalsHR 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 - CohereMediumFrontend EngineerBuild a Credit Card Form With Validation and Linked Input Fields
A front-end UI coding question: build a credit card form with card number, name, expiry and security code, where every field is validated and the fields are linked, so the detected card network changes formatting and security-code rules. It tests state design, caret-safe input formatting, error timing, accessibility and safe handling of card data.
Software Engineering FundamentalsOnsite - CohereMediumMachine Learning EngineerBuild an LLM-driven text-game agent
This question tests the ability to design a robust pipeline for an LLM-based agent interacting with a stateful environment, focusing on context management, output validation, and error recovery.
Software Engineering FundamentalsOnsiteLLMPrompt EngineeringSystem Design - CohereMediumMachine Learning EngineerReplace a Heuristic Terminal Text Game's Python Logic With LLM Calls
A live coding round: replace the heuristic Python implementation of a terminal text game with one driven by an LLM while keeping the game playable end to end. AI assistants are allowed, but the round judges your own implementation and debugging, including validating model output, fallbacks, and tests with a fake model.
Software Engineering FundamentalsOnsite - CoinbaseMediumSoftware EngineerBuild Task Management Through Records, Search, Assignment, and Completion
Implement an in-memory task management system that tracks task lifecycles, assignments, and deadlines with efficient indexing and querying. Tests data structure design, state management, and multi-field sorting.
Software Engineering FundamentalsOnline Assessmentdata-structureshash-tablesorting - CoinbaseHardSoftware EngineerDebug and Extend Cursor Queries
This question evaluates understanding of iterator/cursor semantics, stateful side effects and mutation, practical debugging and trace reasoning, and basic query API design such as adding limit or order_by features.
Software Engineering FundamentalsOnsite - CoinbaseHardSoftware EngineerDesign a Timestamped Cloud Credit Ledger with Rebates, Merges, and History
Design an in-memory cloud credit ledger that processes top-ups, charges with delayed deterministic rebates, account merges with canonical alias resolution, historical balance lookups, and spending leaderboards.
Software Engineering FundamentalsOnline AssessmentData StructuresDesignHeap - CoinbaseMediumSoftware EngineerDesign a task management system with TTL
This question evaluates the ability to design in-memory data models and algorithms for time-based task assignment semantics, including TTL-based expiration, per-user quotas, priority-based listing, and correct handling of multiple concurrent assignments and completion rules.
Software Engineering FundamentalsOnline Assessment - 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 - 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 - 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 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 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 - CoinbaseHardSoftware EngineerPick Mempool Transactions for a Block with Parent Dependencies and CPFP
A multi-part coding problem about filling a block of capacity 100 from a large, unsorted mempool of transactions with fees and sizes, where speed matters more than optimality. Later parts add parent transactions that must be included first, child-pays-for-parent across multi-level chains, and an optional minimum fee for a new child.
Software Engineering FundamentalsTechnical Screen - Color HealthMediumSoftware EngineerBuild and Review an Employee Expense Reimbursement Application
This problem tests your ability to design a simple RESTful API and implement core CRUD operations with server-side validation for an expense tracking system.
Software Engineering FundamentalsTechnical ScreenAPI DesignCRUDValidation - ComposioMediumSoftware EngineerGenerate a Semantic Dependency Graph from Tool Schemas
Design an algorithm to construct an explainable dependency graph between API tools by matching output and input schemas and identifying unresolved requirements.
Software Engineering FundamentalsOnline AssessmentGraph AlgorithmsData ProcessingSchema Matching - ConfluentMediumSoftware EngineerDesign an LRU Cache with a Constant-Time Average
Design a fixed-capacity LRU cache whose get, put, and current-value average operations all run in expected constant time. Reason through map and recency-list invariants, running-sum updates, replacement and eviction edge cases, numeric precision, overflow, and tests that catch aggregate or ordering bugs.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerDocument Search: Exact Word Match, Non-Adjacent Phrase Match and AND/OR Queries
A progressive coding round that builds search over a collection of documents. It starts with exact whole-word lookup, extends to multi-word queries whose words need not be adjacent, and ends with words combined by AND and OR, testing inverted indexes, set operations and clarifying ambiguous query semantics.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerExplain Linux Command Execution, Filesystems, and Isolation
Explain what Linux does from shell parsing through process creation, exec, waiting, and exit status, then trace paths, permissions, file descriptors, directories, procfs, and network inspection. Compare containers and virtual machines through their actual isolation boundaries and operational trade-offs.
Software Engineering FundamentalsOnsite - ConfluentHardSoftware EngineerExplain variadic functions
Explain variadic functions 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 - ConfluentMediumSoftware EngineerImplement tail -n for a Very Large File
Implement the core of tail -n for a seekable file that may be many gigabytes without scanning it all when the requested suffix is small. Work through backward block reads, chunk boundaries, trailing-newline semantics, bounded memory, binary-versus-text handling, safe decoding, and mutation assumptions.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerMachine Coding: Word Search and Ordered Phrase Search Across a List of Documents
A machine-coding exercise that asks you to build a search component over a list of text documents, first finding the documents that contain a given word and then those where a phrase's words appear in the same sequence. It tests tokenization choices, index design, and handling of repeated words and edge cases.
Software Engineering FundamentalsOnsite
Citadel Securities
Cloudflare
Cohere
Coinbase
Confluent