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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 2731–2760 of 5874 results

  • InstacartMediumSoftware Engineer
    Design a task system with assignments

    This question tests your ability to design a flexible data model for a task-assignment system, focusing on efficient lookups and state management in an in-memory environment.

    Software Engineering FundamentalsTechnical ScreenSystem DesignData StructuresAPI Design
  • InstacartMediumSoftware Engineer
    Design an Inventory Service with Reservations, Hot SKUs and Oversell Prevention

    A system design question about an inventory management service that reserves stock while customers check out. It tests how a candidate prevents overselling under concurrent updates, handles hot SKUs, manages reservation expiry and idempotency, and supports partial fulfillment of multi-item orders.

    System DesignOnsite
  • InstacartMediumSoftware Engineer
    Design an Inventory Service with Stock Reservations That Prevents Overselling

    A system design discussion of an inventory service that reserves stock for orders, centered on reservations, concurrent updates and preventing overselling. It probes how stock and holds are modeled, how a reservation stays atomic under contention, how abandoned holds are released and how hot items scale.

    System DesignTechnical Screen
  • InstacartMediumSoftware Engineer
    Design an inventory management system

    This question evaluates competency in system design, data modeling, distributed consistency, concurrency control, API design, idempotency, and scalability for backend inventory and reservation workflows.

    System DesignOnsite
  • InstacartMediumSoftware Engineer
    Design an inventory system

    This question evaluates a candidate's competency in designing inventory and distributed systems, covering stock tracking models, reservation and commit semantics, concurrency control, data modeling, API design, and real-time integrations.

    System DesignHR Screen
  • InstacartMediumSoftware Engineer
    Design and Release a Consistent Dark-Store Inventory System

    Design a strongly consistent micro-fulfillment (dark-store) inventory system that handles reservations, stock reconciliation, and idempotent retries, alongside a zero-downtime deployment strategy.

    System DesignOnsitesystem-designdistributed-transactionsinventory-management
  • InstacartHardSoftware Engineer
    Design cloud storage with quotas and compression

    This question evaluates a candidate's ability to design a multi-tenant cloud storage system, testing competencies in API design, quota accounting, compression strategies, distributed storage architecture (partitioning, replication/erasure coding), consistency models, security, versioning, and observability.

    System DesignOnline Assessment
  • InstacartHardSoftware Engineer
    Design product catalog service

    This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Design product catalog service states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    System DesignOnsite
  • InstacartHardSoftware Engineer
    Design scalable inventory system and avoid races

    This question evaluates a candidate's ability to design scalable, highly available distributed systems with robust concurrency control and consistency reasoning, covering architecture, data modeling, caching, message-based integration, and operational concerns like observability and disaster recovery.

    System DesignOnsite
  • InstacartMediumSoftware Engineer
    Discuss an Interesting Project and a Deployment Mistake

    Tests an engineer's ability to articulate complex technical architecture, evaluate architectural tradeoffs, take ownership of production failures, and demonstrate long-term operational growth.

    Behavioral & LeadershipOnsitebehavioralsystem-reliabilityproduction-incidents
  • InstacartEasySoftware Engineer
    Evaluate Ordered Variable Definitions with Addition and Subtraction

    Evaluate ordered variable definitions and plus/minus expressions with an explicit directional grammar, while distinguishing assignment lookup from general equation solving.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Evaluate a Target Variable from Assignments with Plus, Minus, Cycles and Conflicts

    A three-part coding exercise that computes a target variable's value from a list of assignment equations. It starts with right-hand sides that are numbers or other variables, adds addition and subtraction with cross-references, and finally requires an empty string for cycles, undefined variables and conflicting assignments.

    Software Engineering FundamentalsTechnical Screen
  • InstacartMediumSoftware Engineer
    Evaluate a Variable from Chained Assignments with +/- Expressions and Cycle Detection

    A coding problem that evaluates a target variable from chained assignments such as T1 = T2 and T2 = 5, then extends to right-hand sides with plus and minus and to inputs that may contain cycles. It tests parsing, memoized dependency resolution and cycle detection that does not flag shared dependencies.

    Software Engineering FundamentalsOnsite
  • InstacartMediumSoftware Engineer
    Evaluate an arithmetic expression

    This question tests the ability to evaluate a mathematical string containing integers, addition, subtraction, multiplication, and division, requiring an understanding of operator precedence and the use of stacks.

    Coding & AlgorithmsTechnical ScreenStackParsingMath
  • InstacartMediumSoftware Engineer
    Evaluate arithmetic expression using DFS

    This question evaluates a candidate's understanding of expression parsing and evaluation using depth-first traversal, covering competencies in recursive descent or stack-based DFS, operator precedence, unary operators, and 64-bit integer division semantics with truncation toward zero.

    Coding & AlgorithmsHR Screen
  • InstacartMediumSoftware Engineer
    Evaluate arithmetic expression with precedence

    Instacart software-engineer onsite coding question: implement an arithmetic expression evaluator for a string of non-negative integers, +, -, *, /, parentheses, and spaces. It tests operator precedence and associativity, unary minus, 64-bit intermediates, integer division truncating toward zero, and robust handling of invalid input via a two-stack, shunting-yard, or recursive-descent parser.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Evaluate dependent variable expressions

    This question evaluates a candidate's ability to parse and evaluate assignment expressions, resolve inter-variable dependencies, and detect cycles or unsolvable references.

    Coding & AlgorithmsOnsite
  • InstacartHardSoftware Engineer
    Evaluate query ratios from equations

    This problem tests your ability to model algebraic relationships as a weighted directed graph and perform pathfinding to calculate ratios between variables.

    Coding & AlgorithmsTechnical ScreenGraphBFS/DFSMath
  • InstacartMediumSoftware Engineer
    Explain Technical Tradeoffs in a Project You Led

    Discuss a led project through concrete technical alternatives, implementation details, personal ownership, coordination, and supported outcomes.

    Behavioral & LeadershipOnsite
  • InstacartMediumSoftware Engineer
    Explain your biggest project with trade-offs

    This question evaluates technical leadership, system-design trade-off analysis, communication, and conflict-resolution competencies by probing a candidate's most impactful project, role, technical design choices, and a real teammate disagreement.

    Behavioral & LeadershipOnsite
  • InstacartMediumSoftware Engineer
    Implement a pivot table transformation

    This question evaluates competency in data transformation and aggregation, specifically pivot operations, time-based grouping, null handling, dimensionality reduction (top‑K/OTHER), scalability for large datasets, and expressing solutions in both Python (pandas or pure) and SQL within the Data Manipulation (SQL/Python) domain.

    Data Manipulation (SQL/Python)Onsite
  • InstacartMediumSoftware Engineer
    Implement an In-Memory File Storage System

    This question evaluates the ability to design and implement efficient in-memory data structures and algorithms for stateful file management, covering string-keyed storage, size accounting, querying and sorting, and user quota enforcement.

    Coding & AlgorithmsOnline Assessment
  • InstacartMediumSoftware Engineer
    Implement bus route simulation features

    This question evaluates a candidate's skills in stateful event-driven simulation, data-structure and algorithm design for capacity-constrained boarding and dropping logic, and statistical downsampling to preserve origin–destination demand distributions.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Implement matrix-indexing and expression resolver

    This question evaluates a candidate's ability to parse structured text files, perform matrix indexing with a nonstandard origin convention, reconstruct data across multiple blocks, and resolve symbolic variable expressions and dependencies for arithmetic evaluation in the Coding & Algorithms domain.

    Coding & AlgorithmsOnsite
  • InstacartMediumSoftware Engineer
    Implement multiple coding round problems

    This problem tests your ability to manage a time-sensitive priority queue, handle dynamic variable substitution in expressions, and optimize for streaming data processing.

    Coding & AlgorithmsTechnical ScreenHeapStackParsing
  • InstacartMediumSoftware Engineer
    Implement prefix and suffix file search

    This question evaluates the ability to design and implement efficient string-indexing data structures and APIs for prefix-and-suffix matching, demonstrating competency with tries, suffix-related structures, inverted indexes, and time/space complexity trade-offs.

    Coding & AlgorithmsOnline Assessment
  • InstacartHardSoftware Engineer
    Implement store, evaluator, and parser

    This problem tests your ability to design a robust in-memory data store with versioning and TTL, implement an expression evaluator for dependencies, and parse a specialized stream of matrix data.

    Coding & AlgorithmsOnsiteData StructuresHashingRecursion
  • InstacartMediumSoftware Engineer
    Implement timestamped task management system APIs

    This question evaluates a candidate's ability to design and implement time-ordered in-memory data structures and APIs, testing competencies in temporal event ordering and precedence, scheduled deletions, priority-sorted retrieval, user-task assignment, and historical (time-travel) queries.

    Coding & AlgorithmsOnline Assessment
  • InstacartHardSoftware Engineer
    Implement worker time and payroll tracker

    This problem tests your ability to manage overlapping time intervals, perform efficient lookups on historical state changes, and calculate cumulative payroll based on dynamic shift rates.

    Coding & AlgorithmsOnline AssessmentIntervalsBinary SearchData Structures
  • InstacartHardSoftware Engineer
    Library Catalog and Lending System: Five-Phase Engineering Assessment

    This problem tests the ability to design an extensible lending system, implement a search algorithm with concurrency constraints, and debug race conditions in a multi-threaded environment.

    Software Engineering FundamentalsOnline Assessmentconcurrencydata-structuressystem-design