practice a little every day, paws crossed ♡
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 1891–1920 of 2336 results
- RipplingMediumSoftware EngineerDesign in-memory delivery billing core APIs
This problem tests your ability to design an efficient in-memory service for managing delivery billing, requiring careful consideration of concurrency, precision in monetary calculations, and optimized aggregation of billable events.
System DesignOnsiteConcurrencyData StructuresAPI Design - RipplingMediumSoftware EngineerHow would you present a project deep dive?
This question evaluates communication, technical ownership, architectural reasoning, decision-making, and impact measurement competencies, and is categorized as Behavioral & Leadership with relevance to system design and product execution; it tests both conceptual understanding and practical application.
Behavioral & LeadershipOnsite - RipplingMediumSoftware EngineerImplement Food Delivery Billing
This problem tests your ability to implement complex billing logic involving conditional fee structures, time-based surcharges, and data aggregation.
Coding & AlgorithmsOnsiteAlgorithmsDatetimeData Processing - 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 - RipplingMediumSoftware EngineerImplement an In-Memory File System
Design and implement an in-memory file system supporting directory creation, file appending, reading, and lexicographically sorted path listings.
Coding & AlgorithmsOnsitetrietreedesign - RipplingHardSoftware EngineerPresent a Project and Reflect
This question assesses the candidate's ability to articulate the end-to-end lifecycle of a complex project, focusing on technical decision-making, team collaboration, and the ability to critically analyze one's own performance.
Behavioral & LeadershipOnsiteBehavioralLeadershipCommunication - RipplingMediumSoftware EngineerPrevent Duplicate Payments Under High Load
Design a highly reliable payment processing system that guarantees exactly-once execution and prevents duplicate charges during high-concurrency spikes and downstream failure scenarios.
System DesignOnsiteDistributed SystemsPaymentsConcurrency - RipplingMediumSoftware EngineerStaff Engineer Hiring-Manager Round: Platform Ownership, AI Adoption, and Cross-Team Influence
This question assesses the candidate's ability to drive complex, cross-functional engineering initiatives and their strategic approach to integrating emerging technologies like AI into legacy or established platforms.
Behavioral & LeadershipOnsiteLeadershipSystem ArchitectureStakeholder Management - RipplingMediumSoftware EngineerTrack article votes and last three flips
This question evaluates a developer's ability to design in-memory data structures that support constant-time vote updates, score aggregation, and recent flip-event tracking while handling vote-change semantics.
Coding & AlgorithmsOnsite - RipplingMediumSoftware EngineerWhy do you want to join this company?
This question evaluates a candidate's ability to articulate past experience and measurable impact, communicate clear motivation, and demonstrate fit for a specific team or company, targeting communication, self-presentation, leadership, and career-alignment competencies for a Software Engineer role.
Behavioral & LeadershipOnsite - 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 - RobinhoodHardSoftware EngineerCount Unique Dependents in a Referral DAG
Count unique direct and transitive dependents in a DAG, preserving edge direction, ignoring unknown endpoints, and handling shared descendants without double-counting.
Coding & AlgorithmsOnsite - RobinhoodMediumSoftware EngineerDefend the Complexity and Scalability of a Project
Prepare a project deep dive that withstands repeated questions about technical difficulty and scalability. Define your ownership, defend a genuine trade-off with evidence, identify current bottlenecks, and propose incremental scaling only when measurable signals justify it.
Behavioral & LeadershipOnsite - 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 EngineerDesign Payment Processing with Idempotency and Reconciliation
Design a resilient payment processing system that interfaces with third-party payment gateways, guarantees exactly-once execution via idempotency, manages complex payment state machines, and resolves discrepancies via reconciliation.
System DesignOnsitePaymentsIdempotencyDistributed Systems - RobinhoodMediumSoftware EngineerDesign a Cron Job Scheduler for 100K Jobs With At-Least-Once Execution
A system design question about a cron job scheduler that stores about 100,000 recurring job definitions, runs up to 10,000 jobs at once and guarantees at-least-once execution. It tests data modeling, including whether a schedule belongs on the job, finding and dispatching due jobs at scale, and failure handling with leases and retries.
System DesignOnsite - RobinhoodHardSoftware EngineerDesign a Distributed Scheduler with At-Most-Once Runs
Design a distributed scheduler around strict at-most-once run starts, durable identities, ambiguous crashes, SLA failures, queue recovery, logs, and notification outboxes.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign a Fault-Tolerant Distributed Job Scheduler
This question tests the ability to design a distributed, fault-tolerant system capable of scheduling and executing tasks reliably at scale, emphasizing durability, state management, and consistency.
System DesignOnsiteDistributed SystemsReliabilityTask Queues - RobinhoodMediumSoftware EngineerDesign a Photo Management Service
This question evaluates a candidate's ability to design scalable, reliable photo management systems, focusing on API design, storage architecture, metadata modeling, album management, and operational concerns for large numbers of users and photos.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign a Task Scheduler and Executor
Design a high-scale task scheduler for one-time, cron-like, fixed-rate, and fixed-delay execution. Cover versioned task and attempt states, due-time indexing, safe concurrent claims, retries, leases, backpressure, idempotency, recurrence semantics, and recovery.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign a constrained cache and secure string validator
This question tests the ability to implement a thread-safe, size-constrained cache (LRU-like) and robust string validation logic for identifying malformed or potentially malicious input strings.
Coding & AlgorithmsOnsiteConcurrencyLRUHashing - RobinhoodMediumSoftware EngineerDesign a distributed job scheduler
This question tests the ability to design a fault-tolerant, scalable distributed system capable of scheduling one-time and recurring background tasks with guaranteed execution semantics.
System DesignOnsiteDistributed SystemsScalabilityDatabase Design - RobinhoodMediumSoftware EngineerDesign a live and historical stock quote API fed by a redundant exchange trade feed
A system design question that asks for a stock quote API serving live prices at about 10 million requests per second and one-day, one-month and one-year history at about 1 million, fed by two redundant exchange trade connections. It tests sequence-number arbitration, gap replay, fan-out of live state, bar aggregation and caching at scale.
System DesignOnsite - RobinhoodMediumSoftware EngineerDesign a referral leaderboard with chain-based counts
This question evaluates a candidate's ability to model and compute transitive referral counts using graph-like structures and efficient data structures, testing skills in algorithm design, counting, and sorting within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - RobinhoodMediumSoftware EngineerDesign an At-Most-Once Job Scheduler
This question tests the ability to design a distributed, fault-tolerant job scheduler that guarantees tasks are executed no more than once, focusing on state management and concurrency control.
System DesignOnsiteDistributed SystemsConcurrencyFault Tolerance - RobinhoodMediumSoftware EngineerDesign an Order Execution System for Market and Limit Orders with Cancellation
A system design question about building the order execution system for a retail brokerage, where users place market and limit orders and can cancel them. It tests order execution flow, order state transitions with partial fills and cancels, failure handling, tracking user balances, and scaling the design to millions of orders.
System DesignOnsite - 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
Rippling
Robinhood