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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 2971–3000 of 3640 results
- RobinhoodMediumSoftware EngineerDesign authorization and audit logging systems
This question tests your ability to design a scalable, low-latency authorization framework and a reliable, tamper-proof audit logging system for a financial platform.
System DesignOnsiteSecurityAuthorizationAudit Logging - RobinhoodHardSoftware EngineerExplain Project Complexity and Scalability in a Deep Dive
Prepare a project deep dive that explains data flow, business invariants, personal ownership, measured bottlenecks, and credible scalability tradeoffs.
Behavioral & LeadershipOnsite - 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 - RobinhoodMediumSoftware EngineerHandle security vs velocity conflicts across teams
This question evaluates a candidate's competency in balancing security requirements with product delivery speed, encompassing risk assessment, stakeholder management, trade-off communication, and ownership of execution and follow-through.
Behavioral & LeadershipOnsite - RobinhoodMediumSoftware EngineerMaintain Fractional Stock Inventory Across Orders
Simulate sequential customer fractional buy and sell orders, using scaled integer arithmetic to maintain the firm's remaining inventory between 0 and 1 share while tracking whole-share market executions.
Coding & AlgorithmsOnsitesimulationmathhash-table - RobinhoodMediumSoftware EngineerParse Requests and Compute Balances
This problem tests your ability to parse structured text commands, manage relational state between users, and implement transactional logic with integrity constraints.
Coding & AlgorithmsOnsiteHash MapGraphParsing - RobinhoodMediumSoftware EngineerProduce a Deterministic Course Plan
Return the lexicographically smallest valid course order from prerequisite pairs, or report a cycle. Handle duplicate edges, malformed IDs, self-dependencies, empty course sets, and large graphs with deterministic topological sorting.
Coding & AlgorithmsOnsite - RobloxMediumData ScientistAnalyze Recent Orders Dataset with Python/pandas
This question evaluates proficiency in data manipulation and aggregation using Python/pandas, including extracting per-user maximums, computing overall summary statistics, and producing daily aggregates from time-stamped records.
Data Manipulation (SQL/Python)Onsite - 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 - RobloxHardSoftware EngineerCount Distinct Hat Assignments and Maximize Hat Points
Count valid one-hat-per-person assignments and maximize assigned-hat points with exact counts, unique hat use, and bitmask or backtracking reasoning.
Coding & AlgorithmsOnsite - RobloxMediumData ScientistDefend a metric choice under scrutiny
This question evaluates a Data Scientist's competency in metric selection, stakeholder communication, and experiment governance when defending a non-obvious primary metric.
Behavioral & LeadershipOnsite - RobloxHardSoftware EngineerDefine success metrics and monitoring
Define success metrics and monitoring evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationOnsite - RobloxMediumMachine Learning EngineerDesign a Game Recommendation System
This problem tests your ability to design a multi-stage recommendation architecture tailored to a gaming platform, focusing on user-specific constraints like age-appropriateness and the challenges of the long-tail game distribution.
ML System DesignOnsiteRecommendation SystemsSystem DesignRanking - RobloxMediumFrontend EngineerDesign a Reusable Dropdown Menu Component
Tests a candidate's ability to architect a production-grade, reusable UI component library element with consideration for flexible API design, accessibility (WAI-ARIA), state management, and large dataset performance.
System DesignOnsiteFrontend System DesignReactAccessibility - RobloxMediumSoftware EngineerDesign a Scalable Like Counter
This question tests the ability to design a high-throughput, eventually consistent counting system that handles massive concurrent write volumes while maintaining low-latency read access.
System DesignOnsiteScalabilityDistributed SystemsCaching - RobloxHardSoftware EngineerDesign a Static Audio Detection System
This question evaluates system design and ML integration skills for building a scalable, reliable offline audio detection pipeline, including ingestion, preprocessing, STT and spectral feature extraction, rule-based post-processing, artifact persistence, and human-in-the-loop review within the ML system design domain.
ML System DesignOnsite - RobloxMediumMachine Learning EngineerDesign a game genre classifier
This question assesses the ability to design an end-to-end multi-modal machine learning system for classifying user-generated game content based on diverse input features and real-time serving requirements.
ML System DesignOnsiteMulti-modalNLPComputer Vision - RobloxHardSoftware EngineerDesign a scheduled payment system
This question evaluates proficiency in designing a reliable, scalable scheduled payment service, testing competencies in distributed systems, API design, scheduling and execution workflows, idempotency and deduplication, time semantics, transactional consistency, security and compliance, and operational monitoring.
System DesignOnsite - RobloxMediumSoftware EngineerDesign an In-App Notification Center with Real-Time Updates and Unread Counts
A system design question about an in-app notification center that turns product events into per-user notifications, shows an unread badge and a recent list, and pushes new items to online users. It tests fan-out strategy, inbox data modeling, unread counts, real-time delivery, reliability, and client design.
System DesignOnsite - RobloxMediumSoftware EngineerDesign favorites and social game recommendations
This question tests the ability to design a scalable, low-latency system for managing user-specific lists (favorites) and integrating real-time social signals into a game recommendation engine.
System DesignOnsiteScalabilityCachingSocial Graphs - RobloxHardSoftware EngineerDesign real-time game matchmaking service
This question evaluates a candidate's competence in designing scalable, low-latency distributed systems and matchmaking algorithms, including skills in queue management, skill-based matching, regional sharding, SLO-driven latency targets, consistency models, failure handling, and monitoring.
System DesignOnsite - RobloxHardSoftware EngineerDesign resource loader and ROS-like pub/sub
This question evaluates system design and distributed-systems competencies including resource management, async concurrency, caching and eviction, streaming and partial loads, dependency resolution, failure isolation, observability, and pub/sub concerns such as topic/schema/versioning, discovery, QoS, ordering, replay, partitioning, latency, clock semantics, and security. Commonly asked to assess architectural reasoning about scalability, low-latency trade-offs, fault tolerance, and deployment/topology choices, it is categorized under System Design and tests both high-level conceptual understanding and practical application-level design decisions; English.
System DesignOnsite - RobloxMediumSoftware EngineerDesign robot path boundedness with repeats
This question evaluates algorithmic skills in parsing compressed instruction strings, finite-state simulation, and spatial reasoning to determine path boundedness, and it belongs to the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerDetect robot state after movements
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Detect robot state after movements states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - RobloxMediumSoftware EngineerDetect runs and collapse a numeric grid
This question evaluates proficiency in 2D array manipulation, pattern detection for contiguous runs, and state simulation involving removal and gravity-like collapse of elements.
Coding & AlgorithmsOnsite - RobloxMediumFrontend EngineerExecutive-Round Behavioral: Proactive Decision-Making in Career and Projects
This question assesses the candidate's ability to demonstrate agency, self-reflection, and proactive decision-making when navigating complex professional transitions and high-stakes technical trade-offs.
Behavioral & LeadershipOnsiteBehavioralLeadershipDecision-Making - RobloxMediumMachine Learning EngineerFind Windows Containing a Target
This problem tests your ability to efficiently filter and identify intervals within a collection that satisfy specific containment constraints using two-pointer or sliding window techniques.
Coding & AlgorithmsOnsiteArraysFilteringIntervals - RobloxMediumMachine Learning EngineerFind target-heavy sliding windows
This question tests the ability to implement an efficient sliding window algorithm to analyze frequency-based patterns within a data stream or array.
Coding & AlgorithmsOnsiteSliding WindowAlgorithmsArray
Robinhood
Roblox