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Software 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
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- 546
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- 11
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- 8
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Showing 5101–5130 of 5874 results
- SoFiHardSoftware EngineerScale a key-value store with consistent hashing
Scale a key-value store with consistent hashing 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 DesignTechnical Screen - SocureHardSoftware EngineerImplement a Concurrent Payment Queue with Visibility Timeouts
Implement a thread-safe in-memory payment queue supporting atomic message consumption, visibility timeouts, receipt-handle validation to prevent stale ACKs, and idempotent submissions.
Software Engineering FundamentalsTechnical ScreenConcurrencyData StructuresMessage Queues - SonatusHardSoftware EngineerCompute days until a higher reading
This question evaluates proficiency in array processing and the next-greater-element concept, measuring algorithmic reasoning about sequence traversal, comparisons, and managing time/space trade-offs.
Coding & AlgorithmsTechnical Screen - SonatusHardSoftware EngineerDesign a RAG system for vehicle documents
This question evaluates a candidate's ability to design a Retrieval-Augmented Generation system, testing competencies in information retrieval, vector search, document ingestion and chunking, metadata modeling, citation handling, security, observability, and scalability within the system design and NLP/information-retrieval domain.
System DesignTechnical Screen - SotiMediumSoftware EngineerDesign an IP blacklist API
This question evaluates API and backend system design skills for network security and distributed caching, encompassing data modeling for exact IPs and CIDR ranges, cache architecture and invalidation, consistency and failure handling, scaling, and observability.
System DesignOnsite - SpacexEasySoftware EngineerAlign Telemetry Streams and Publish Versioned Corrections
Define telemetry subtraction semantics, handle missing or repeated timestamps, and reconcile late events with versioned, idempotent corrections.
Software Engineering FundamentalsTechnical Screen - SpacexEasySoftware EngineerDebug Missing Output from a Python Multiprocessing Pool
Diagnose and fix issues in a Python multiprocessing script where asynchronous workers fail to produce output, addressing pool lifecycle management, exception propagation, and centralized file I/O.
Software Engineering FundamentalsTechnical Screenpythonmultiprocessingconcurrency - SpacexMediumSoftware EngineerDynamic Island Counts
Report the exact island count after each land addition by tracking only activated cells and merging distinct neighboring components efficiently.
Coding & AlgorithmsTechnical Screen - SpeakHardSoftware EngineerDesign scenario-based speaking feature
This question evaluates system-design competency in building scalable, real-time, multilingual audio-driven learning features, including product modeling, session orchestration, audio pipelines (ASR/TTS), personalization, localization, telemetry, and privacy/security considerations.
System DesignOnsite - SpeakHardSoftware EngineerDesign speaking scenarios and auth/profile API
This question evaluates a candidate's ability to design scalable, real-time speaking-practice features and a minimal authentication/profile API, encompassing system architecture, service decomposition, data modeling, ASR/LLM integration, personalization, security and privacy, and operational concerns like scaling and observability.
System DesignOnsite - SpeakMediumSoftware EngineerImplement auth and profile APIs
This question evaluates backend API design competencies such as authentication and bearer-token access control, user profile data modeling, input validation, error handling, and state management for an in-memory service within the System Design category.
Software Engineering FundamentalsOnsite - Sprinter HealthMediumSoftware EngineerDesign a Game Store with Purchases, Downloads, and Reviews
Design connected game-store pages for category browsing, purchases, authorized downloads, and reviews with consistent data and retry behavior.
System DesignTechnical Screen - Sprinter HealthMediumSoftware EngineerDesign a scalable game app store
This question evaluates a candidate's ability to design a scalable backend system, covering competencies in system architecture, data modeling, distributed services, media asset delivery, secure transactional flows, and operational trade-offs around scalability, availability, and consistency.
System DesignOnsite - SquareMediumSoftware EngineerBuild a Trust-Aware BIN Database
Build an in-memory card-prefix database that resolves brand and card type independently across overlapping writes. Practice combining longest-prefix matching with trust and recency rules while preserving omitted fields and supporting heavy lookup traffic.
Coding & AlgorithmsOnsite - SquareMediumSoftware EngineerExplain an AI-Assisted Engineering Workflow You Can Defend
Use one real project to explain the path from ambiguous requirements through design, implementation, launch, and maintenance, with AI assistance treated as a bounded tool. Show stakeholder alignment, decision trade-offs, independent verification, rejected output, and post-launch learning.
Behavioral & LeadershipOnsite - SquareHardSoftware EngineerImplement transaction network queries
This question evaluates the ability to model and query dynamic graph connectivity and reachability for pairwise transactions, testing competencies in graph representation, dynamic data structures, and reachability queries within the Coding & Algorithms domain and emphasizing practical application of algorithmic concepts.
Coding & AlgorithmsTechnical Screen - SquareMediumSoftware EngineerLead a High-Leverage Project in a Regulated Legacy System
Prepare a senior project deep dive spanning business leverage, personal ownership, delegation, architecture, migration, performance, reliability, and cost. Extend the analysis to regulated legacy systems where reconciliation, auditability, controlled rollout, and silent correctness failures matter.
Behavioral & LeadershipOnsite - SquareEasySoftware EngineerList the Two-by-Two Blocks Covering Each Black Cell
This problem tests your ability to navigate grid coordinates, implement range boundaries, and perform efficient dictionary-based data collection.
Coding & AlgorithmsTechnical ScreenArraysHash MapsGrid - SquarepointEasySoftware EngineerApply Insert, Update, and Remove Operations to a Keyed Store
Implement an in-memory key-value store processor that executes insert, update, and remove commands with strict handling for missing or duplicate keys, returning the final state in deterministic order.
Coding & AlgorithmsOnsiteHash MapDesignString - SquarepointMediumSoftware EngineerDefend a Redis Choice and Explain Database Index Trade-offs
This question evaluates architectural decision-making around data access patterns, comparing the introduction of an in-memory cache like Redis against optimizing relational database indexing and query plans.
Software Engineering FundamentalsHR ScreenDatabase IndexingRedisSystem Design - SquarepointMediumSoftware EngineerEvaluate Linear Regression Assumptions and Fit Three Points
Discuss the assumptions behind ordinary least squares, how multicollinearity affects a fitted model, and practical ways to address multicollinearity and overfitting. Cover data and labels, leakage-safe features, baselines and model choice, offline evaluation, deployment constraints, monitoring, and drift.
Machine LearningTechnical Screen - SquarepointMediumSoftware EngineerExplain Core Python Runtime and Language Concepts
Assesses foundational Python runtime semantics and language mechanics, focusing on mutability, generator behavior, concurrency models under the GIL, and robust resource management.
Software Engineering FundamentalsHR Screenpythonconcurrencymemory-management - SquarepointEasySoftware EngineerExplain Database Indexes and Why Every Column Should Not Be Indexed
Explain database indexes, selective lookups, write overhead, composite keys, and why indexing every column can hurt a mixed workload.
Software Engineering FundamentalsOnsite - SquarepointEasySoftware EngineerExplain Python Immutability, Tuples, Hash Tables, and Caller-Level Errors
Practice Python tuple rebinding, shallow immutability, hash-table insertion and complexity, and caller-level handling of record-operation errors.
Software Engineering FundamentalsOnsite - SquarepointMediumSoftware EngineerFind the Correlation Between Two Die-Face Counts
A fair six-sided die is rolled independently `n` times, where `n` is a fixed positive integer. Explain the assumptions and derivation clearly, check edge cases, and show how the result changes when those assumptions no longer hold.
Statistics & MathTechnical Screen - SquarepointMediumSoftware EngineerFind the Most Frequent Character with a Tie-Breaker
Tests string traversal, frequency counting, and deterministic tie-breaking under large input constraints.
Coding & AlgorithmsHR ScreenStringsHash TableCounting - SquarepointHardSoftware EngineerImplement and Improve React Components
Implement and Improve React Components 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 - SquarepointMediumSoftware EngineerParse payroll file and answer queries
This question evaluates proficiency in robust file parsing, schema-driven data modeling, type conversion, validation, duplicate handling, and implementing aggregate and ranking queries using Python's standard library for messy, delimited payroll data.
Coding & AlgorithmsOnline Assessment - SquarepointMediumSoftware EngineerReturn Elements Greater Than the Overall Average
This problem tests your ability to perform a two-pass linear scan on an array to compute an aggregate statistic and filter elements, emphasizing space complexity and data integrity.
Coding & AlgorithmsHR ScreenArraysMathTwo-pass - SquarepointHardSoftware EngineerSolve two coding assessment tasks
This question set evaluates algorithmic optimization and string-processing skills: the first problem focuses on maximizing cumulative revenue from limited inventories (optimization and greedy reasoning with dynamic value updates), while the second focuses on case-insensitive text parsing, word frequency counting, and frequency-based ordering.
Coding & AlgorithmsOnline Assessment
SoFi
Square
Squarepoint