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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 1831–1860 of 2336 results

  • PinterestMediumSoftware Engineer
    Reconstruct route from unordered travel tickets

    This problem tests your ability to model a graph where each edge represents a transition, requiring you to find a valid linear sequence that visits every node exactly once.

    Coding & AlgorithmsOnsiteGraphsHash MapLinked List
  • PinterestMediumSoftware Engineer
    Settle debts with minimal transactions

    Pinterest software-engineer onsite coding question: given a list of debts as (debtor, creditor, amount) triples, return settlement transfers that clear every net balance using the minimum number of transactions. It tests reducing to net balances, recognizing the problem is NP-hard, backtracking with pruning to find the optimum for small N, and a heap-based greedy heuristic plus correctness and time/space complexity analysis for large, skewed debt graphs.

    Coding & AlgorithmsOnsite
  • PinterestMediumSoftware Engineer
    Solve Four Interview Coding Problems

    This set tests proficiency in graph algorithms, binary search on sorted data, grid simulations, and custom data structure design for real-time leaderboards.

    Coding & AlgorithmsOnsiteGraphsBinary SearchSimulation
  • PinterestMediumSoftware Engineer
    Solve set equality and ad log top‑K

    This multi-part question evaluates set and multiset operations, frequency counting, top-K computation over time windows, sliding-window and streaming data structures, and character-multiset matching for string construction within the coding & algorithms domain.

    Coding & AlgorithmsOnsite
  • PinterestMediumSoftware Engineer
    Track 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
  • PitchbookEasySoftware Engineer
    Implement Euclidean distance and k-nearest neighbors

    This question evaluates understanding of Euclidean distance metrics, vector arithmetic, and nearest-neighbor retrieval, testing implementation skills for computing distances and selecting the k closest points.

    Coding & AlgorithmsOnsite
  • PlaidMediumSoftware Engineer
    Design an Embeddable Pay by Bank Widget

    Design a secure, embeddable Pay by Bank frontend widget and supporting backend infrastructure that enables direct bank checkout via an isolated iframe and asynchronous payment processing.

    System DesignOnsiteSecurityWeb ArchitecturePayments
  • PlaidMediumSoftware Engineer
    Explain What You Seek and an Unexpected Project Outcome

    Tests candidate self-awareness, career motivation, and adaptability when technical initiatives diverge from expectations due to real-world constraints.

    Behavioral & LeadershipOnsiteBehavioralCareer GoalsAdaptability
  • PlaidMediumSoftware Engineer
    Reason 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 Engineer
    Design 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
  • PurestorageMediumSoftware Engineer
    Determine whether points form squares

    This question evaluates computational geometry, combinatorial counting, and algorithmic optimization skills by requiring validation of a non-degenerate square from four 2D integer points and counting distinct squares in a larger point set, and it falls under the Coding & Algorithms category.

    Coding & AlgorithmsOnsite
  • Qualified HealthHardSoftware Engineer
    Control LLM Workflow Quotas and Recovery Costs

    Control LLM workflow quotas and 429 retries with shared token budgets, durable checkpoints, and explicit handling of uncertain requests and duplicate billing.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Enforce Tenant and Session Isolation in an Agent RAG System

    Isolate tenants and sessions across RAG retrieval, caches, prompts, and tools, with server-enforced authorization and layered prompt-injection defenses.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Ingest and Serve RAG Sessions with Up to 200 Documents

    Design a 200-document RAG session pipeline with asynchronous ingestion, corpus readiness, latency budgeting, scoped caching, and quota-aware serving.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Reconcile RAG Document Expiry, Chat History, and Cold Audits

    Design 24-hour document deletion, seven-day chat history, fast sidebar reads, and cold audits while resolving conflicts over derived content and physical erasure.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Recover Durable Workflows with External Effects and Long Waits

    Recover DAG workflows through crashes, duplicate attempts, external side effects, and multi-day approvals using durable state and explicit exactly-once limits.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Scale Mixed I/O and LLM Workflow Execution

    Scale mixed I/O and LLM workflows with separate worker budgets, tenant fairness, tiered state storage, and explicit reconciliation of conflicting workload figures.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Stream LLM Output While Committing Reliable DAG Results

    Stream provisional LLM output to clients while durably validating and committing complete structured results before downstream DAG tasks execute.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Stream and Cancel Agent Responses Without Unsafe Retries

    Design SSE or WebSocket streaming, end-to-end stop handling, and safe Agent retries while distinguishing local cancellation from provider billing and tool effects.

    System DesignOnsite
  • Qualified HealthHardSoftware Engineer
    Validate Editable DAGs and Bound Runtime Repetition

    Validate editable workflow DAGs, reason about cycle-check latency, and enforce durable retry and expansion limits that prevent unbounded runtime loops.

    System DesignOnsite
  • RampHardSoftware Engineer
    Build 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 Engineer
    Design a Payment-Count Dashboard That Scales with Readers and Updates

    Tests candidate's ability to design a real-time, low-latency financial metrics dashboard that evolves from a simple relational database setup to a horizontally scalable, stream-aggregated architecture resilient to duplicate events and counter drift.

    System DesignOnsitesystem-designdistributed-systemsstream-processing
  • RampHardSoftware Engineer
    Design 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 Engineer
    Implement 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 Engineer
    Implement 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
  • RampHardSoftware Engineer
    Present a System You Designed

    This question tests your ability to articulate a complex technical project, demonstrating architectural decision-making, ownership, and the ability to evaluate trade-offs in a real-world scenario.

    Behavioral & LeadershipOnsiteSystem DesignArchitectureLeadership
  • RampMediumSoftware Engineer
    Spreadsheet String Concatenation with Dependent Cells

    Build a fixed-grid string spreadsheet with concatenation formulas, dependency updates, repeated references, and read-time circular-reference errors.

    Coding & AlgorithmsOnsite
  • RampHardSoftware Engineer
    Traverse an HTTP Maze with Retry Handling

    This problem tests BFS traversal skills combined with state management for handling intermittent network failures and API constraints.

    Coding & AlgorithmsOnsiteBFSGraphAPI
  • RedditEasySoftware Engineer
    Design a game leaderboard service

    This question tests the ability to design a high-throughput, low-latency leaderboard service capable of handling frequent rank updates and read requests for millions of active users.

    System DesignOnsiteCachingDatabasesScalability
  • RedditMediumSoftware Engineer
    Design comment-likelihood prediction platform

    This question evaluates a candidate's competency in ML system design and infrastructure, covering feature pipelines, feature store strategy, training/serving consistency, online inference at high QPS, and production monitoring.

    ML System DesignOnsite