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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.
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Showing 601–630 of 1208 results
- Jump TradingHardSoftware EngineerDesign a Compact Columnar File Format
Design an append-friendly, compact columnar file format optimized for fast analytical scans over tabular financial market data (e.g., tick feeds or order book snapshots). Define the on-disk binary layout, reader/writer abstractions, serialization rules, and operational trade-offs.
Software Engineering FundamentalsTechnical Screensystems-designfile-formatscolumnar-storage - KikoffEasySoftware EngineerBuild a Robust Log Parser and Prefix-Operator Search
Implement a log parser and query engine that converts raw server log lines into structured records and supports filtering via prefix-operator tokens.
Software Engineering FundamentalsTechnical ScreenString ParsingData StructuresSoftware Architecture - KikoffEasySoftware EngineerValidate a Third-Party Identity Payload
Implement a pipeline that validates a third-party identity verification response against schema requirements and business rules while returning sanitized failure reason codes.
Software Engineering FundamentalsTechnical ScreenData ValidationPythonClean Code - LatitudeaiMediumBackend EngineerDesign a Thread-Safe Bounded Blocking Queue
Tests your ability to design a concurrent, thread-safe bounded blocking queue using synchronization primitives, handle edge cases like spurious wakeups and timeouts, and cleanly coordinate shutdown across multiple threads.
Software Engineering FundamentalsOnsiteConcurrencyMultithreadingQueue - LayerzeroMediumSoftware EngineerChoose a Safe Polling Strategy for Delayed Records
Evaluate whether delayed arrivals can support a fixed polling interval that always yields exactly one new record. Use worst-case reasoning, then define a practical live contract covering observation limits, warm-up, buffering, cursors, deduplication, retries, out-of-order data, and multiple pollers.
Software Engineering FundamentalsTechnical Screen - LegoraMediumBackend EngineerDesign a Cloud-Agnostic Upload Adapter
Design a provider-neutral object storage upload client that unifies cloud SDK behaviors while supporting streaming, multipart uploads, error normalization, and provider-specific escape hatches.
Software Engineering FundamentalsOnsiteapi-designcloud-storageobject-oriented-design - LegoraMediumSoftware EngineerDesign a Cloud-Provider Upload Adapter
Design a modular, provider-agnostic upload adapter interface that enables clients to perform direct uploads to cloud storage (e.g., S3, GCS, Azure Blob). The problem evaluates object-oriented API design, error normalization, capability negotiation, and idempotent verification workflows.
Software Engineering FundamentalsOnsiteapi-designobject-oriented-designcloud-storage - LiftoffMediumSoftware EngineerDesign and implement core Tetris game logic
This question evaluates practical implementation skills in game logic, real-time state and event management, piece rotation and movement handling, line-clearing algorithms, and clean, testable code organization.
Software Engineering FundamentalsOnsite - LilaMediumMachine Learning EngineerDebug a Transformer bug in an unfamiliar repo
This question tests your ability to identify and rectify a logical error in a Transformer's multi-head self-attention mechanism, specifically focusing on tensor dimensionality, causality masking, and numerical stability.
Software Engineering FundamentalsOnsiteTransformersDeep LearningDebugging - LinkedInMediumSoftware EngineerDesign a Raffle Drum That Draws Duplicate Tickets Fairly in O(1)
Design a drum that holds raffle ticket codes, where the same code can be dropped in more than once, and supports adding a ticket, pulling a specific ticket out, and drawing one at random so every physical ticket in the drum is equally likely to come out — all in average O(1) time. Tests combining an array with a hash index so removal and random draw both stay constant time even with string keys and duplicates.
Software Engineering FundamentalsTechnical Screendesignhash-maprandomization - LinkedInMediumSoftware EngineerDesign a meeting scheduler API
This problem tests your ability to design a thread-safe scheduling system using interval management techniques and efficient data structures for range querying.
Software Engineering FundamentalsOnsiteObject-Oriented DesignConcurrencyIntervals - LinkedInMediumSoftware EngineerExplain a Project with a Diagram and Deep Dive into Your Design
Communicate a project through a simple data-flow diagram, then explain design choices, implementation ownership, failure behavior, and validation.
Software Engineering FundamentalsOnsite - LinkedInMediumSoftware EngineerExplain the Design of a Recent Feature
Tests your ability to communicate software design clearly by breaking down a production feature into its architecture, trade-offs, individual ownership, and verification strategy.
Software Engineering FundamentalsOnsiteSystem DesignTechnical CommunicationArchitecture - LinkedInMediumDevOps EngineerExplore an Unknown Grid and Return a Robot Path
This problem tests graph traversal, state-space representation, and pathfinding in an environment where the map must be discovered dynamically.
Software Engineering FundamentalsOnsiteGraph TraversalBFSState Machine - LinkedInMediumSoftware EngineerImplement map and render to DOM
This question evaluates a candidate's skills in vanilla JavaScript utility implementation and DOM rendering, covering array and plain-object iteration semantics, higher-order functions, input validation, error handling, and safe text rendering for browser environments.
Software Engineering FundamentalsHR Screen - LinkedInHardSoftware EngineerMerge and Serialize N-ary Trees
Tests recursive tree manipulation, immutable merging semantics, and robust string serialization/deserialization with input validation.
Software Engineering FundamentalsTechnical Screentreerecursionparsing - LinkedInMediumSoftware EngineerRandomized String Multiset With Average O(1) Insert, Remove and Weighted Random Pick
Design a collection of strings that allows duplicates and supports insert, remove and a random pick in average constant time, where each stored occurrence is equally likely to be returned. It tests hash map and array layout, index bookkeeping on removal, and how string keys change the cost analysis.
Software Engineering FundamentalsTechnical Screen - Luma AIMediumSoftware EngineerReverse-Engineer an App's Undocumented API and Rebuild It With Better UX
A take-home asks you to reverse-engineer the undocumented API behind an existing app and rebuild the app with a better user experience, then review its fragility and extend it with safe write support. Tests API discovery, schema inference, resilient client design, credential and legal judgment, and UX scoping.
Software Engineering FundamentalsOnsite - LyftMediumSoftware EngineerDesign a Globally Versioned Key-Value Store
Design a globally versioned key-value store with sparse key histories, binary-search reads, atomic version publication, and correct history retention.
Software Engineering FundamentalsOnsite - LyftMediumSoftware EngineerDesign a Transactional In-Memory Key-Value Store
Design a transactional in-memory key-value store with correct value counts, efficient rollback, and explicitly defined command semantics.
Software Engineering FundamentalsOnsite - LyftMediumSoftware EngineerImplement Stateful Fetch-N over a Paginated Upstream
Implement a stateful fetchN wrapper over a paginated upstream that returns items in source order across repeated calls. Define buffering, page-token progression, exhaustion, empty pages, invalid input, and retry behavior without losing or duplicating items.
Software Engineering FundamentalsOnsite - LyftMediumSoftware EngineerIn-Memory Key-Value Store with Nested Begin, Commit, and Rollback Transactions
A coding question to implement an in-memory key-value store with begin, set, unset, commit and rollback, where transaction blocks can be nested and committed changes can no longer be rolled back. It tests how state is recorded per block, restoring keys that were absent, nested commit semantics, and operation complexity.
Software Engineering FundamentalsOnsite - LyftMediumSoftware EngineerWrapper Over a Paginated Page API That Fetches the Next N Words
A coding question that wraps an external paginated API, where each page returns a variable number of words, behind a fetch(n) method that returns the next n words in order. It tests handling words left over between calls, requests that span several or empty pages, lazy fetching, the end of the content, and API failures.
Software Engineering FundamentalsOnsite - MathWorksMediumSoftware EngineerCompare Core Networking and Language Runtime Concepts
Compare pointer ownership and storage duration, HTTP with HTTPS, and TCP with UDP using concrete technical examples. Strong responses separate guarantees from common implementations, connect concepts to production failures, and avoid simplistic claims about memory or network speed.
Software Engineering FundamentalsOnsite - Maven SecuritiesHardQuantitative TraderSolve Graduate Trader Probability Questions
This set evaluates quantitative reasoning and probabilistic thinking, testing competencies in combinatorics, probability, expectation, conditional probability, enumeration, and logical deduction.
Software Engineering FundamentalsOnline Assessment - MercorMediumSoftware EngineerCharge-Then-Save: Making a Checkout Handler Safe Under Retries
Review a ticket-checkout handler that bills a card through a remote gateway and then saves an order row, explain every way it breaks when calls fail or are retried, and redesign it. Tests reasoning about partial failure, idempotency, and reconciliation.
Software Engineering FundamentalsTechnical Screenidempotencydistributed-systemspayments - MercorMediumSoftware EngineerCode Review: A Ride Fare Method That Charges a Card Then Logs the Trip
Review a Java method that charges a rider's card through an external processor and then writes a trip record, and explain what goes wrong if the caller fails mid-call and how to fix it.
Software Engineering FundamentalsTechnical Screencode-reviewidempotencydistributed-systems - MercorEasySoftware EngineerCode Review: Find the Problems in a Python Dict-Based Memoization Cache
A Python code review question about a function that memoizes an expensive computation in a module-level dictionary. It tests whether a candidate can find correctness, memory, concurrency and key-equality problems in simple caching code and propose fixes with clear trade-offs.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerCode Review: Improve a Java Method That Builds a CSV String
A Java code-reading question: review a short method that concatenates a list of rows into a CSV string and propose improvements. It tests knowledge of string-building performance, separator and escaping rules for CSV, null handling, streaming output for large exports, and risks when files are opened in spreadsheets.
Software Engineering FundamentalsTechnical Screen - MercorMediumSoftware EngineerCode Review: Partial Failure in a Java Payment Method That Charges Then Records
A Java code-reading question about a payment method that charges an external provider and then inserts a database record, focused on what happens when the client fails in the middle of the call. It tests reasoning about partial failures, retries, idempotency keys, payment states, and reconciliation with the provider.
Software Engineering FundamentalsTechnical Screen
Liftoff
LinkedIn
Luma AI
Lyft
MathWorks
Mercor