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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.
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- 546
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Showing 1–30 of 84 results
- AirbnbMediumSoftware EngineerBuild an Incremental Loyalty-Points Ledger with Scheduled, Cancelable Transfers
Implement an in-memory loyalty-points ledger that grows in three stages: atomic transfers between accounts, transfers scheduled for a future point on a simulated clock, and cancellation of a transfer before it fires. Tests incremental state-machine design, validating before mutating, and keeping point totals correct across every sequence of calls.
Software Engineering FundamentalsOnline Assessmentstate-machineoopsimulation - AirbnbMediumSoftware EngineerDefine a File Store with User Quotas and Compression
Implement an in-memory cloud file store that supports file creation, copying, prefix/suffix search, per-user storage quotas, and atomic file compression/expansion.
Software Engineering FundamentalsOnline AssessmentData StructuresDesignString - AirbnbMediumSoftware EngineerDesign a Multi-Level In-Memory Cloud Storage Service
Design a multi-tiered in-memory cloud storage system supporting staged uploads, capacity limits, prefix search ranking, and conflict-aware backup and restore operations.
Software Engineering FundamentalsOnline AssessmentDesignData StructuresHash Table - AirbnbMediumSoftware EngineerDesign a Stateful Banking System with Scheduled Payments and Account Merges
Design an in-memory stateful banking system that supports account creation, transfers, spending leaderboards, scheduled payments with deterministic backlog processing, and account merges.
Software Engineering FundamentalsOnline Assessmentdata-structuresheapsystem-simulation - AirbnbHardSoftware EngineerDesign a Stateful Working Hours Register
Design an in-memory working hours and compensation tracking register that supports badge events, top-k leaderboards, scheduled rate changes, and interval-based historical earnings calculations.
Software Engineering FundamentalsOnline AssessmentDesignIntervalsBinary Search - AirbnbEasySoftware EngineerDesign an In-Memory Cloud Storage Service with Users, Backups, and Restore
Implement an in-memory cloud storage system supporting user storage limits, globally unique files, ranked file queries, account merges, and transactional backup and restore operations.
Software Engineering FundamentalsOnline AssessmentObject-Oriented DesignData StructuresHash Table - AirbnbMediumSoftware EngineerImplement a Multi-Level Recipe Management Service
Design and implement an in-memory recipe management service supporting deterministic querying, defensive data isolation, atomic updates, and secondary index maintenance.
Software Engineering FundamentalsOnline AssessmentData StructuresAPI DesignInverted Index - AirbnbHardSoftware EngineerImplement a Time-Aware Banking System
Design and implement a stateful, time-aware in-memory banking ledger that handles atomic transfers, deferred/scheduled executions, account mergers, historical balance queries, and activity rankings.
Software Engineering FundamentalsOnline AssessmentDesignHeapBinary Search - AirbnbMediumSoftware EngineerImplement a Time-Aware Task Management System
Design and implement an in-memory, time-aware task management class that supports scheduling, rescheduling, canceling, and prioritized polling based on timestamps and priorities.
Software Engineering FundamentalsOnline AssessmentHeapHash TableSystem Design - AirbnbMediumSoftware EngineerIn-Memory Banking System with Immediate, Offline and Deletable Transfers
Implement an in-memory banking system across progressive levels: create users, move money immediately, accept offline transfers that take effect later, and delete transfers that have not completed. It tests state modeling, validation before mutation, conservation of money across every sequence of operations, and extensible class design.
Software Engineering FundamentalsOnline Assessment - AirbnbHardSoftware EngineerIn-Memory Banking System: Transfers, Top Spenders, Scheduled Payments, Account Merges
A four-level in-memory banking system: create accounts, deposit and transfer, rank top spenders by outgoing value, run scheduled payments that must execute in timestamp order before every later operation, and merge accounts while keeping both balances and histories. It tests incremental class design and time-ordered state.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerIn-Memory Workspace Credit System With Transfers, Top-K and Scheduled Transfers
Implement an in-memory workspace credit system in levels: create workspaces, add credit and transfer it instantly, return the top K workspaces, then schedule and cancel future transfers that must take effect before each later operation. It tests clean state management, deterministic ordering, time-based processing and extensible code under a tight time limit.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerTask Management System: Priorities, Name Search, User Quotas and Expiring Assignments
A four-level coding assessment that builds an in-memory task management system: adding, updating and retrieving tasks, name search and priority listing, users with quotas and expiring time-based assignments, then task completion and overdue reporting. It tests extensible design, deterministic ordering and time handling.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerTimestamped Parcel Attribute Store With Compare-and-Set, Prefix Listing and TTL
Implement a timestamped in-memory store of parcel attributes with overwriting set, get and a compare-and-set update, then list attributes as name(value) sorted by name with an optional prefix filter, and finally add per-attribute TTLs that hide expired values. It tests precise operation semantics, expiry rules and incremental class design.
Software Engineering FundamentalsOnline Assessment - AirbnbMediumSoftware EngineerWorkspace Credit Ledger: Transfers, Top-K, Scheduled Transfers, Merges, Balance History
A four-level coding assessment that builds an in-memory credit ledger for workspaces, much like bank accounts. Levels add deposits, instant transfers with a top-k ranking, scheduled transfers with cancellation, and account merges with historical balance lookups, testing stateful class design, time handling and edge cases.
Software Engineering FundamentalsOnline Assessment - AmazonHardSoftware EngineerDebug Failing Tests in a Django Movie Search and Filter API
Debug an existing Django movie catalog API whose automated tests fail, covering URL routing, query parameter handling, queryset filters on genre, director, writer, rating and year, result ordering with tie-breakers, and HTTP 500 errors. It tests a systematic, layer-by-layer debugging process under a time limit.
Software Engineering FundamentalsOnline Assessment - AmazonMediumSoftware EngineerDebug Watch List Movie Operations
This question evaluates backend debugging, RESTful API semantics, data validation and integrity, persistence behavior, and correct HTTP status and error-response handling for watch-list movie operations.
Software Engineering FundamentalsOnline Assessment - AmazonHardSoftware EngineerDebug a Layered Book Search Service Against Five Search Rules
Given a layered bookstore search backend with planted bugs, write failing tests for substring matching, scope selection, case-insensitivity, multi-key ordering and visibility, then locate and fix every defect without changing the API contract. Tests test-first debugging across layers and query design.
Software Engineering FundamentalsOnline Assessmentdebuggingtestingsearch - AmazonMediumSoftware EngineerDebug a Node.js car-rental backend: leaked cars, missing new cars, lost edits
An unfamiliar Node.js car-rental backend with API documentation and failing preset tests has three independent bugs: the My Cars list shows other users' cars, newly added cars never appear, and edits vanish after a refresh. The question tests systematic debugging, ownership checks across endpoints, and confirming that writes really persist.
Software Engineering FundamentalsOnline Assessment - AmazonMediumSoftware EngineerDebug a Test-Driven C++ Project
Tests your ability to design and implement a sliding-window rate limiter with deduplication and state cleanup, reflecting common logic and edge-case errors encountered when debugging test-driven C++ systems.
Software Engineering FundamentalsOnline AssessmentSliding WindowDesignHash Table - AmazonMediumSoftware EngineerDesign a TTL-Aware LRU Cache Without Full Expiration Scans
Design a TTL-aware LRU cache with synchronized access, capacity eviction, and expiration heaps or timing wheels instead of full-table scans.
Software Engineering FundamentalsOnline Assessment - AmazonHardSoftware EngineerDiagnose Return Eligibility Scoring Bugs
This question evaluates debugging and root-cause analysis skills related to scoring logic, data integrity, feature engineering, and system reliability in return-eligibility services.
Software Engineering FundamentalsOnline Assessment - AmazonHardSoftware EngineerFix a Broken Podcast Episode Search Against Five Behavior Rules
Fix a broken podcast episode search function so it matches substrings case-insensitively, supports searching by title, host, or both, sorts results correctly, and excludes unpublished episodes.
Software Engineering FundamentalsOnline Assessmentdebuggingtestingsearch - AmazonHardSoftware EngineerFix a Buggy Spring Boot Movie Search Against Five Search Rules
From an Amazon online assessment: fix a buggy Spring Boot movie search backend so that search is partial-match and case-insensitive, can target titles, stars or all fields, sorts by popularity with further keys, and returns only published movies. It tests debugging layered code, query logic and test-first verification.
Software Engineering FundamentalsOnline Assessment - AmazonMediumSoftware EngineerFix the Password Reset Workflow
Implement and debug a stateful password reset manager that handles token generation, time-to-live (TTL) expiry, brute-force attempt limits, and single-use token invalidation.
Software Engineering FundamentalsOnline AssessmentAuthenticationState MachineSecurity - AmazonMediumSoftware EngineerImplement Review Content Moderation
This problem tests your ability to design a content moderation service that efficiently checks for prohibited words and maintains a running count of violations per user using a stateful metadata store.
Software Engineering FundamentalsOnline AssessmentHash MapsData StructuresState Management - AmazonMediumSoftware EngineerRepair a Django Post-Creation Endpoint and Its React Contract
Implement and repair a Django REST Framework view and serializer for post creation to satisfy frontend React contract requirements, ensure atomic tag associations, and enforce authenticated author assignment.
Software Engineering FundamentalsOnline AssessmentDjangoREST APIDatabase Transactions - AmericanMediumSoftware EngineerStructure a Pizza-Ordering System with Four Discount Policies
Design an extensible object-oriented order pricing system for a pizzeria that models pizzas, applies four distinct discount policies with specific composition rules, and returns an itemized, explainable receipt.
Software Engineering FundamentalsOnline AssessmentObject-Oriented DesignDesign PatternsData Structures - BitkernelMediumSoftware EngineerAnalyze TCP three-way handshake states
This question evaluates understanding of TCP connection establishment and the TCP state machine, testing recognition of correct state transitions during the three-way handshake and related transport-layer behavior.
Software Engineering FundamentalsOnline Assessment - BitkernelMediumSoftware EngineerChoose best prompt for AI code debugging
This question evaluates a candidate's competency in prompt engineering and AI-assisted debugging, focusing on structuring diagnostic information, providing error context, and communicating expected versus actual behavior.
Software Engineering FundamentalsOnline Assessment
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