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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
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 121–150 of 5874 results
- AirbnbHardSoftware EngineerDesign rental watchlist and notification system
This question evaluates system architecture and scalability competencies, including data modeling for date-range watchlists, event-driven notification pipelines, time-zone and DST handling, consistency and concurrency semantics, idempotency, sharding/caching strategies, and privacy/analytics considerations.
System DesignOnsite - AirbnbHardSoftware EngineerDesign scalable notification system
Airbnb's onsite system design round asks you to design a notification system that delivers email, SMS, and push messages to millions of guests, hosts, and employees, supporting both event-triggered sends and large batch campaigns. A complete answer covers requirements and scale math, architecture and data flow for both modes, the data model and API, templating, user preferences and compliance, prioritization, deduplication and idempotency, retries and failover, scaling and backpressure, observability, and cost. This walkthrough gives a corrected end-to-end reference answer for every part, including the trade-offs interviewers probe.
System DesignOnsite - AirbnbHardSoftware EngineerDetect overlap of two linked lists with cycles
This problem tests your ability to detect if two linked lists merge, specifically when they may contain cycles, by requiring logic to identify loop entry points and intersection nodes.
Coding & AlgorithmsOnsiteLinked ListTwo PointersCycle Detection - AirbnbMediumSoftware EngineerDetermine Exact Layover Booking
Determine if a subset of layover activities can be booked such that their total cost exactly matches a target voucher balance, handling floating-point currency without precision loss.
Coding & AlgorithmsTechnical ScreenDynamic ProgrammingBacktrackingSubset Sum - AirbnbMediumSoftware EngineerDiscuss learning and feedback experiences
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Discuss learning and feedback experiences states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipTechnical Screen - AirbnbMediumSoftware EngineerExplain why you want to join Airbnb
This question evaluates a software engineer's ability to articulate authentic motivation, product literacy, and cultural fit in a values-focused interview round. It tests how well candidates can connect their engineering background to real organizational problems and communicate genuine alignment — skills commonly assessed in the culture and behavioral rounds of technical interview loops.
Behavioral & LeadershipTechnical Screen - AirbnbMediumSoftware EngineerFind minimal property set in neighborhood
This question evaluates combinatorial optimization and algorithm design skills, focusing on capacity-constrained selection (subset-sum/knapsack-style reasoning), deterministic tie-breaking, and complexity analysis within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - AirbnbMediumSoftware EngineerFind palindrome-forming string pairs
This question evaluates string-processing and algorithmic design skills, including knowledge of efficient lookup data structures, palindrome properties, handling of edge cases, and time/space complexity analysis.
Coding & AlgorithmsOnsite - AirbnbMediumSoftware EngineerFind smallest permutation under constraints
This problem tests your ability to manipulate digits and understand greedy strategies to construct the smallest possible number after applying specific constraints.
Coding & AlgorithmsOnsiteGreedyRecursionStrings - AirbnbHardSoftware EngineerFlatten a Nested Integer List
Flatten an arbitrarily deep mixture of integers and lists while preserving left-to-right order. The challenge emphasizes an iterative stack solution that handles empty lists, very deep nesting, and up to 200,000 nodes without mutating the input.
Coding & AlgorithmsOnsite - AirbnbHardSoftware EngineerHow do you conduct a code review exercise?
This question tests a software engineer's ability to conduct structured, high-signal code reviews under time pressure and limited context. It evaluates judgment in prioritizing correctness issues over style, communicating feedback clearly, and handling ambiguity — core competencies in software engineering fundamentals interviews.
Software Engineering FundamentalsOnsite - AirbnbMediumSoftware EngineerImplement Connect Four game
This question evaluates implementation skills for game state management, move handling, and efficient winner-detection algorithms, testing competence in data structures, algorithmic complexity analysis, and correctness under edge cases.
Coding & AlgorithmsTechnical Screen - AirbnbMediumSoftware EngineerImplement Connect Four with win detection
This question evaluates a candidate's ability to design efficient data structures and algorithms for real-time game state management, including win detection, API design, time/space complexity analysis, and handling edge cases such as full or out-of-range columns.
Coding & AlgorithmsOnline Assessment - AirbnbEasySoftware EngineerImplement Text Layout and Query Parsing
Implement URL query parameter extraction and a greedy text line-wrapper that enforces maximum line length and prevents orphan words on the final line.
Coding & AlgorithmsTechnical ScreenStringsParsingGreedy - 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 - AirbnbEasySoftware EngineerImplement a Removable Nested-List Iterator
Design and implement a nested-list iterator supporting `hasNext`, `next`, and an in-place `remove` operation that alters the original data structure.
Coding & AlgorithmsTechnical ScreenDesignStackRecursion - 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 EngineerImplement a reservation widget with pricing
This question evaluates skills in frontend component state design, data modeling, pricing computation, validation logic, error handling, and API integration for a lodging reservation widget.
Software Engineering FundamentalsOnsite - AirbnbHardSoftware EngineerImplement retry wrapper and interdependent validators
This question evaluates a candidate's competence in building robust asynchronous utilities and form validation logic, covering retry/backoff strategies, error classification, per-attempt and overall timeouts, cancellation via AbortSignal, observable retry hooks, cross-field validators, state management, and accessibility considerations in JavaScript/TypeScript web applications. Category: Other / Miscellaneous; domain: web development and systems reliability in JavaScript/TypeScript; it is commonly asked because it probes both conceptual understanding of retry semantics, cancellation and validation constraints and practical implementation skills related to API ergonomics, error propagation, composable validators, and performance trade-offs.
Software Engineering FundamentalsOnsite - 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 EngineerMaximize path score in DAG
This question evaluates proficiency in graph algorithms and optimization, focusing on reasoning about weighted directed acyclic graphs and maximizing a path score that combines node rewards and edge time costs.
Coding & AlgorithmsTechnical Screen - AirbnbMediumSoftware EngineerMaximize profit from non-overlapping jobs
This question evaluates proficiency in weighted interval scheduling, dynamic programming concepts, and the use of efficient data structures for large-scale scheduling problems, including handling duplicate times, large reward values, and memory constraints.
Coding & AlgorithmsOnsite - AirbnbHardSoftware EngineerMaximize sum with no adjacent tree nodes
This problem tests your ability to use tree-based dynamic programming to solve an optimization challenge where you must select a subset of nodes with no two being adjacent, while maximizing the sum of their values.
Coding & AlgorithmsOnsiteTree DPRecursionDFS - AirbnbMediumSoftware EngineerPrioritize consumer product opportunities
This question evaluates a candidate's ability in product strategy, data-driven user research, metric design, and prioritization within the product/decision-making domain for a consumer mobile application.
Behavioral & LeadershipOnsite - AirbnbHardSoftware EngineerProcess a Timestamped Workspace Credit Ledger
Design and implement an in-memory timestamped credit ledger that supports deposits, transfers, spending with delayed cashback rewards, account merges, balance queries, and spend rankings.
Coding & AlgorithmsOnline AssessmentData StructuresDesignHeap - AirbnbMediumSoftware EngineerRender Wrapped Paragraphs Inside One Text Box
Implement a text formatting utility that wraps multiple paragraphs at distinct per-paragraph widths and renders them inside a single, uniformly padded ASCII border box.
Coding & AlgorithmsOnsiteStringGreedyImplementation - AirbnbMediumSoftware EngineerReview Python geodata code
This question evaluates proficiency in Python code review and geolocation data-processing, including competencies in readability, correctness, performance optimization, and architectural scalability.
Coding & AlgorithmsOnsite
Airbnb