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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 331–360 of 448 results
- PinterestHardSoftware EngineerAI-Assisted Coding: Add a Read-Through Cache for a Product GET API in an Existing Repo
In an AI-assisted coding round, add a read-through cache to an existing service so a product GET API calls ProductRepository less often, then explain the approach. It tests understanding a codebase before prompting, cache placement, expiry, invalidation and concurrency, and proving the change works.
Software Engineering FundamentalsOnsite - PinterestMediumSoftware EngineerBuild an emoji blaster animation on iOS
This question evaluates a developer's skills in iOS UI interaction, animation frameworks, event scheduling and concurrency, performance optimization, and designing testable application architecture.
Software Engineering FundamentalsOnsite - PinterestMediumSoftware EngineerImplement tap-to-infect color grid on iOS
This question evaluates proficiency in mobile UI architecture, grid data structures, connected-component algorithm reasoning, and state management concerns such as undo and memory/stack safety within the mobile app development and iOS domain.
Software Engineering FundamentalsOnsite - PinterestMediumSoftware EngineerReason About Nested JSON Schema Validation
Design and implement a recursive JSON schema validator that checks nested objects and arrays, enforces required properties, and returns precise failure paths for validation errors.
Software Engineering FundamentalsOnsiteJSON SchemaRecursionTree Traversal - PinterestMediumSoftware EngineerTrack a User's Top Trending Viewed Pin Within a Sliding Time Window
A data structure design exercise: track the Pins a user has viewed within a sliding time window and, at any moment, return the one with the highest trending score. It asks for methods to add a viewed Pin, remove expired Pins and query the top Pin, plus the runtime complexity of each operation.
Software Engineering FundamentalsOnsite - PlaidMediumSoftware EngineerReason About Rate Limiting Under Memory and Throughput Pressure
Tests the candidate's ability to design a high-throughput, memory-bounded rate limiter using bucketed counters instead of unbounded timestamp queues, balancing concurrency, memory overhead, and precision.
Software Engineering FundamentalsOnsiteRate LimitingConcurrencyData Structures - PurestorageMediumSoftware EngineerDesign a thread-safe event dispatcher
This question evaluates understanding of concurrent programming and thread-safe design, including synchronization primitives, race-condition avoidance, listener lifecycle semantics, and event-delivery guarantees.
Software Engineering FundamentalsOnsite - RampHardSoftware EngineerBuild a Resilient Chain of Clue-Driven HTTP Requests
Implement a resilient HTTP traversal client that follows a sequence of clue-bearing API responses to reach a final payload while enforcing safety policies like loop detection, retry budgets, deadline management, response size caps, and origin-scoped auth tokens.
Software Engineering FundamentalsOnsitehttpnetworkingdistributed-systems - RampHardSoftware EngineerDesign a Tunable Recurring-Transaction Detector
Design and implement a configurable, explainable detector that identifies recurring subscription transactions from noisy transaction logs, handling price variations, irregular cadences, and missing cycles.
Software Engineering FundamentalsOnsitealgorithmssystem-designfinancial-data - RampHardSoftware EngineerImplement a Clean In-Memory Transaction Ledger
Design an in-memory double-entry style financial transaction ledger that supports atomic transfers, strict balance invariants, and idempotency key handling.
Software Engineering FundamentalsOnsiteSystem FundamentalsData StructuresIdempotency - RampHardSoftware EngineerImplement and Defend an AI-Assisted Repository Change
Tests your ability to implement a new feature in a simulated unfamiliar codebase using AI tools responsibly, identifying subtle generated bugs, ensuring test coverage, and defending every architectural and implementation decision.
Software Engineering FundamentalsOnsitecode-auditfinancial-ledgerclean-code - RipplingMediumSoftware EngineerDesign Extensible Interview Coding Systems
This problem tests your ability to design an extensible rule-evaluation engine using object-oriented principles, specifically focusing on decoupling evaluation logic from business requirements.
Software Engineering FundamentalsOnsiteObject-Oriented DesignDesign PatternsExtensibility - RipplingMediumSoftware EngineerDesign Raw and Computed Spreadsheet Views
Design raw and computed spreadsheet views with formula parsing, dependency replacement, cache invalidation, atomic edits, and undo semantics.
Software Engineering FundamentalsOnsite - RipplingMediumSoftware EngineerDesign a Data-Driven Expense Rule Evaluator
Design an extensible, data-driven expense policy engine that evaluates structured JSON rules against submitted expenses without requiring code deployments.
Software Engineering FundamentalsOnsiterule-enginesystem-designood - RipplingMediumSoftware EngineerImplement a RESTful Q&A service
This question evaluates a candidate's ability to design and implement a RESTful web service, covering HTTP API design, CRUD operations, data modeling and persistence choices, input validation, pagination/sorting, and basic testing and documentation practices.
Software Engineering FundamentalsOnsite - RipplingHardSoftware EngineerImplement a minimal local HTTP server
This question evaluates proficiency in network programming, HTTP/1.1 protocol parsing, concurrent server design, request routing and security (including path traversal protection), observability, testing, and graceful shutdown using only the language standard library.
Software Engineering FundamentalsOnsite - RipplingMediumBackend EngineerProcess a Task List: Deduplicate, Drop Completed, Sort by Priority, and Nest Subtasks
Senior backend coding question: process a batch of scheduler tasks by removing duplicates on description and due date, dropping completed tasks, sorting by priority, and placing each subtask directly after its parent. It tests clarifying ambiguous policies, orphan and cycle handling, O(n log n) design, and verified use of an AI coding assistant.
Software Engineering FundamentalsOnsite - RobinhoodMediumSoftware EngineerClarify Friendship Rules and Money-Transfer Semantics Before Choosing an Algorithm
Clarify friendship and money-transfer requirements, separate graph reachability from accounting, and reason about a conditional implementation and invariants.
Software Engineering FundamentalsOnsite - RobinhoodMediumSoftware EngineerDefine and Calculate Employee Referral Counts
Implement an algorithm to compute direct and total downstream referral counts for every employee in a directed graph that may contain duplicates, converging paths, and cycles.
Software Engineering FundamentalsOnsiteGraphBFSDFS - RobinhoodMediumSoftware EngineerExplain auth, key rotation, secrets, and incident response
This question tests your knowledge of secure microservice communication, the lifecycle management of sensitive credentials, and the operational procedures for mitigating security breaches.
Software Engineering FundamentalsOnsiteSecurityMicroservicesAuthentication - RobinhoodMediumSoftware EngineerGive a Project Deep Dive Grounded in Personal Ownership
Tests your ability to present a deep dive into an impactful software project you led or contributed heavily to, emphasizing architectural trade-offs, personal ownership, failure modes, and measurable outcomes.
Software Engineering FundamentalsOnsiteProject Deep DiveSystem ArchitectureBehavioral - RobinhoodMediumSoftware EngineerGive a Technical Deep Dive into a Software Project
Practice a project deep dive covering architecture, personal ownership, implementation decisions, validation, outcomes, and lessons learned.
Software Engineering FundamentalsOnsite - RobloxMediumSoftware EngineerBuild an Auto-Rotating Traffic Light in Vanilla JavaScript Without a Framework
A frontend coding question asking for a traffic light that cycles through its colors automatically, built with plain HTML, CSS, and JavaScript and no framework. It tests state machine design, timer management and cleanup, efficient DOM updates, accessibility, and how to test time-based UI code.
Software Engineering FundamentalsOnsite - RokuMediumBackend EngineerExplain concurrency and distributed fundamentals
This question tests fundamental knowledge of thread-safe collections in Java and core distributed systems architectural patterns, specifically partitioning strategies.
Software Engineering FundamentalsOnsiteJavaConcurrencyDistributed Systems - SIG (Susquehanna)EasySoftware EngineerDesign a Cash Register with Inventory and Profit Tracking
Design an object-oriented cash register that manages multi-lot product inventory using FIFO accounting, executes atomic multi-item sales, and accurately tracks realized gross profit.
Software Engineering FundamentalsOnsiteObject-Oriented DesignData StructuresQueue - SIG (Susquehanna)MediumSoftware EngineerFind and Fix C++ Ownership Bugs: Double Free, Shallow Copy, and Object Slicing
Tests a candidate's ability to identify and fix critical C++ resource management bugs, specifically shallow copies leading to double-free errors and object slicing caused by improper pass-by-value semantics with polymorphic types.
Software Engineering FundamentalsOnsiteC++Memory ManagementRAII - SIG (Susquehanna)MediumSoftware EngineerImplement a Simplified std::vector with Manual Memory Management
Tests practical systems programming in C++, specifically decoupling raw memory allocation from object construction, managing dynamic capacity growth, and adhering to the Rule of Five.
Software Engineering FundamentalsOnsitecppmemory-managementdata-structures - SIG (Susquehanna)EasySoftware EngineerIndex a CSV Movie Catalog for Fast Year-Range Queries
Design an immutable movie catalog that parses CSV data and supports fast, inclusive year-range queries using binary search or indexing.
Software Engineering FundamentalsOnsitebinary-searchdata-structurescsv-parsing - SIG (Susquehanna)MediumSoftware EngineerTrees and Binary Search Trees: Taxonomy, Invariant, and Traversal/Search
Tests understanding of binary tree taxonomy, global BST invariants versus local parent-child checks, and efficient tree search under range constraints.
Software Engineering FundamentalsOnsitebinary-search-treetree-traversalrecursion - SalesforceMediumMember of Technical StaffConvert a Sorted Doubly Linked List to a Balanced BST In Place
Tests in-place pointer manipulation and bottom-up tree construction by converting a sorted doubly linked list into a height-balanced binary search tree in linear time.
Software Engineering FundamentalsOnsitelinked-listbinary-search-treerecursion
Pinterest
Plaid
Ramp
Rippling
Robinhood
Roblox
SIG (Susquehanna)
Salesforce