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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
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- 546
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- 11
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- 8
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Showing 181–210 of 625 results
- DecagonMediumSoftware EngineerSolve 3x3 Tic-Tac-Toe with Backtracking: Perfect-Play Result and Best Move
Write a backtracking solver for 3x3 tic-tac-toe that determines the result of a given position under perfect play by both sides and returns a best move for the player to move. It tests win detection, recursive game-tree search, undoing moves correctly, and reasoning about search cost, memoization and pruning.
Software Engineering FundamentalsTechnical Screen - DeshawMediumSoftware EngineerCompare Linux Containers and Virtual Machines
Tests in-depth understanding of Linux operating system virtualization mechanisms, contrasting hardware-level hypervisors with OS-level container isolation primitives across security, performance, and operational dimensions.
Software Engineering FundamentalsTechnical ScreenLinuxOperating SystemsDocker - DeshawMediumSoftware EngineerExplain What Happens When a Linux Shell Runs ls
Tests end-to-end understanding of Linux OS fundamentals, systems programming concepts, system calls, and how a POSIX shell interacts with the kernel to execute a command.
Software Engineering FundamentalsTechnical ScreenLinuxOperating SystemsSystem Calls - DisneyMediumSoftware EngineerImplement a Set Data Structure with a Resizable Array, Then Improve It with Hashing
Tests low-level data structure design by implementing a set from scratch using an array-backed hash table, focusing on collision resolution, dynamic resizing, load factor management, and amortized complexity.
Software Engineering FundamentalsTechnical ScreenData StructuresHash TableArrays - DisneyMediumSoftware EngineerThread-Safe Buffered Batch Writer for Streaming Records into a Database
Design and implement a thread-safe batch buffer that collects streaming records from multiple producer threads and flushes them to a database using batch inserts based on size, timeout, or shutdown triggers.
Software Engineering FundamentalsTechnical ScreenConcurrencyMultithreadingData Structures - DoorDashMediumSoftware EngineerBuild a Delivery Payout Calculation API
Build a payout endpoint that retrieves delivery activity and accrues 30 cents per minute for each concurrent order. The solution covers interval sweeps, malformed events, exact money, day boundaries, final rounding, upstream timeouts, retry limits, caching, and layered tests.
Software Engineering FundamentalsTechnical Screen - DoorDashMediumSoftware EngineerBuild a Three-Service Refund Workflow over HTTP
Implement and orchestrate a multi-service refund pipeline over HTTP, ensuring idempotent execution, safe concurrency limits, and crash recovery across separate process boundaries.
Software Engineering FundamentalsTechnical Screendistributed-systemshttp-apisidempotency - DoorDashHardSoftware EngineerDebug a cache incident end-to-end
This question evaluates a candidate's ability to diagnose and debug production cache incidents, testing competencies in distributed caching, observability, incident response, root-cause analysis, and the operational impact on microservice latency.
Software Engineering FundamentalsTechnical Screen - DoorDashMediumSoftware EngineerDesign a Resilient Bootstrap API Aggregator
Design a resilient bootstrap aggregation service that fetches critical initial state for a mobile app on launch. Tests interface design, concurrent I/O, partial failure handling, and operational trade-offs.
Software Engineering FundamentalsTechnical ScreenAPI DesignConcurrencyResilience - DoorDashMediumSoftware EngineerFilter Open Restaurants Through Existing Domain APIs
Implement an orchestrator service that coordinates calls to a directory API and an operating-hours API with bounded concurrency, short-circuit filtering, resilient error handling, and in-memory caching.
Software Engineering FundamentalsTechnical Screenconcurrencycachingsystem-integration - DoorDashMediumSoftware EngineerMake a Courier Pay Workflow Resilient to Downstream Failures
Tests your ability to implement an idempotent, fault-tolerant workflow engine that safely executes financial transactions against an unreliable downstream ledger.
Software Engineering FundamentalsTechnical ScreenDistributed SystemsIdempotencyAPI Design - EaseHardSoftware EngineerBuild a Hash-Table Key-Value Store Without Built-in Dictionaries or Sets
Implement a key-value store class with put, get and remove without using built-in dictionaries or sets, resolving collisions inside the store rather than raising them to callers. It tests hash table mechanics, collision strategies, deletion, resizing and precise average versus worst-case complexity claims.
Software Engineering FundamentalsTechnical Screen - ElasticMediumSoftware EngineerReview a JavaScript flatten PR
This question evaluates a candidate's understanding of JavaScript recursion, array manipulation, API contract reasoning, and correctness when implementing a flatten utility.
Software Engineering FundamentalsTechnical Screen - EliseAIMediumSoftware EngineerAnalyze the Fairness of an Incremental Shuffle
This question tests the ability to analyze algorithm correctness through probability theory and identify common pitfalls in pseudo-random number generation that lead to selection bias.
Software Engineering FundamentalsTechnical ScreenAlgorithmsProbabilityShuffle - EliseAIEasySoftware EngineerRead and Critique a Short Python Function That Randomly Swaps List Elements
A code-reading exercise: assess a short Python function that walks a list and swaps each element with a randomly chosen position at or before it. Tests tracing unfamiliar code, reasoning about whether every ordering is equally likely, input-type edge cases such as strings, and practical code-review judgment.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerExposing a Python Function as a REST Endpoint with FastAPI and Unit Testing It
An interview question on exposing a Python function as a REST API endpoint and testing it. It asks whether FastAPI counts as an endpoint, how an endpoint maps an HTTP request onto a function, and how you unit test such code, with a concrete example that covers edge cases and replaced dependencies.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerPython Abstract Classes and Instance, Class and Static Methods
A Python object-oriented programming interview question on abstract classes and method kinds. It asks what an abstract class is and whether it can be instantiated, how instance, class and static methods differ, what self and cls refer to, and why a static method would live inside a class at all.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerPython Dictionary Internals: Hashing, Collisions, O(1) Lookup and Hashable Keys
A Python fundamentals interview question on how dictionaries store and look up values: what gets hashed, whether different keys can share a hash, how collisions are resolved and why average lookup is constant time. It also tests whether a list can serve as a key and which objects are allowed as keys.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerPython Generators, yield, Lazy Evaluation and How Decorators Work
A Python interview question on generators and decorators. It asks what a generator is, what yield does, why generators use less memory and what lazy evaluation means, then what a decorator actually does under the hood, testing precise language mechanics rather than memorized definitions.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerPython Virtual Environments, Conda and Poetry, and Everyday Linux Commands
A developer tooling interview question on Python virtual environments, why projects need them and how Conda and Poetry fit in, followed by practical Linux experience: which system you work on and which Unix commands you rely on to run and debug jobs on a server.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerRelational Database Indexes: Read/Write Trade-offs and Tuning a Slow SQL Query
A database fundamentals interview question on relational indexes: what an index is, why it speeds up queries, why not every column should be indexed and how indexes affect write performance. It then asks how you would troubleshoot and tune a complex SQL query that runs extremely slowly.
Software Engineering FundamentalsTechnical Screen - EngelhartMediumSoftware EngineerThreads vs Processes, the Python GIL, Multiprocessing and Async I/O
A Python concurrency interview question covering how threads and processes differ, including their memory spaces, when to reach for multiprocessing, what the Global Interpreter Lock is and how it limits CPU-bound threads, and why async I/O is a good fit for network and other I/O-bound workloads.
Software Engineering FundamentalsTechnical Screen - EquinixMediumSoftware EngineerReview AI Platform And Software Fundamentals
This problem tests foundational knowledge in software architecture, AI system design, and data structures by requiring the candidate to explain the trade-offs in building a RAG-based document retrieval system.
Software Engineering FundamentalsTechnical ScreenRAGSystem DesignSOLID - FaireMediumSoftware EngineerDesign an API for Pascal Triangle
This question evaluates API design, HTTP/web-service principles, data modeling, input validation, error handling, and system constraint reasoning when specifying endpoints, request parameters, response schemas, and practical limits.
Software Engineering FundamentalsTechnical Screen - FireworksMediumSoftware EngineerDetect Security Attacks in Text Logs Using Sliding-Window Rules
Write a program that scans large text-format network logs and reports security attacks defined by rules, such as one source IP contacting more than 10 distinct destination IPs within 10 minutes. It tests parsing, per-source sliding-window state, optimizing a slow first version, and designing targeted test cases.
Software Engineering FundamentalsTechnical Screen - FivetranEasySoftware EngineerImplement a SQL Engine's Storage Layer: Create Database, Schema, Table and Row CRUD
Implement the final storage layer of a SQL engine: create databases, schemas, and tables, then insert, select, update, and delete rows with every change persisted to disk. It tests on-disk layout and catalog design, row identity, crash safety and durability, and the trade-offs between log-based and page-based designs.
Software Engineering FundamentalsTechnical Screen - Fora TravelMediumSoftware EngineerDesign Course, Module, and Lesson Progress APIs
Tests your ability to design RESTful APIs and underlying data access patterns for a hierarchical learning management domain (Course -> Module -> Lesson) with authenticated user scoping, idempotent completion updates, and derived completion metrics.
Software Engineering FundamentalsTechnical Screenapi-designdata-modelingauthentication - GatikHardMachine Learning EngineerDesign a YAML-Configured Point-Cloud Transformation Pipeline
Tests software engineering fundamentals and clean object-oriented design in Python by building an extensible, schema-validated point-cloud transformation pipeline with registry patterns and metadata tracking.
Software Engineering FundamentalsTechnical ScreenObject-Oriented DesignPoint CloudData Pipelines - GeneralmotorsMediumSoftware EngineerConnect Monitoring, Circuit Breakers, Rollback, and CI/CD
Tests your ability to architect an end-to-end reliability workflow combining resilient dependency handling, actionable telemetry, and safe continuous deployment with automated rollbacks.
Software Engineering FundamentalsTechnical ScreenSystem DesignCI/CDReliability - GeneralmotorsMediumSoftware EngineerImplement a REST GET Endpoint and Evolve Its Contract Safely
Tests understanding of RESTful API design principles, HTTP semantics, robust error handling, and strategies for backwards-compatible contract evolution.
Software Engineering FundamentalsTechnical ScreenAPI DesignRESTSystem Design
Decagon
Disney
DoorDash
EliseAI
Faire