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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
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Showing 1081–1110 of 2336 results
- Hot Agent StartupMediumSoftware EngineerImplement a Thread-Safe Pub-Sub Service
This question evaluates concurrent programming and thread-safety skills within the Software Engineering Fundamentals domain, focusing on synchronization primitives, message delivery semantics, and coordination between publishers and subscribers at a practical application level.
Software Engineering FundamentalsOnsite - HubSpotHardSoftware EngineerDesign a Netflix-like streaming platform
A HubSpot software-engineer onsite system-design question: design a Netflix-like video streaming platform covering catalog browse by genre and curated rails (Recently Added, Top Ten), search, adaptive-bitrate playback across web, mobile and TV, cross-device resume, and an upload-to-streamable ingest pipeline. It evaluates service decomposition, data models and API contracts, transcoding and CMAF/multi-DRM packaging, CDN and caching strategy, session concurrency and consistency, multi-region failover, observability and A/B testing, graceful degradation, and cost control at millions of concurrent viewers. The worked solution sizes egress and heartbeat load, corrects the common concurrency, resume, and cache-TTL mistakes, and marks the MVP cut line.
System DesignOnsite - HubSpotHardSoftware EngineerDesign a near-real-time weather API
A HubSpot onsite system-design question: build a weather data platform that ingests hourly dumps for ~2,000 U.S. locations and serves the current temperature with an at-most-10-minute freshness SLA. It tests ingestion pipelines, idempotent retries and backfill, caching and invalidation, storage modeling, rate-limit handling, scaling, and observability on freshness SLOs.
System DesignOnsite - HubSpotEasySoftware EngineerDesign an hourly weather crawling service
This question evaluates a candidate's ability to design scalable, reliable data ingestion and delivery systems, covering competencies such as scheduling and crawling, data normalization, storage schema design, idempotent ingestion, rate limiting, retries, and monitoring.
System DesignOnsite - HubSpotEasySoftware EngineerFind a special person using knows(a,b)
This question evaluates algorithmic reasoning about pairwise relation inference using an oracle-style knows(a, b) API and the ability to minimize API calls, testing skills in graph modeling and asymptotic analysis.
Coding & AlgorithmsOnsite - HubSpotMediumSoftware EngineerFind spammer with minimal hasMessaged calls
Find the "spammer" account that messaged every other account but received from none, using only a hasMessaged(a, b) oracle. This is the classic find-the-celebrity problem inverted, solved with a two-phase elimination-then-verify algorithm in O(n) oracle calls and O(1) extra space, with full correctness proof and edge-case handling.
Coding & AlgorithmsOnsite - Hudson River TradingHardSoftware EngineerBuild a Heart Disease Baseline
This question evaluates proficiency in applied machine learning workflows, including data inspection and cleaning, exploratory data analysis, feature engineering, baseline binary classification modeling, and evaluation using Python libraries like pandas and seaborn.
Machine LearningOnsite - Hudson River TradingMediumSoftware EngineerCompare C++ Virtual Dispatch with CRTP
Compare C++ virtual dispatch with CRTP across runtime flexibility, object layout, separate compilation, heterogeneous collections, inlining, code size, diagnostics, ABI stability, and measured performance.
Software Engineering FundamentalsOnsite - Hudson River TradingMediumSoftware EngineerDesign a Fixed-Size Memory Allocator with Correct Alignment
Design a slab-backed fixed-size allocator with constant-time free-list operations, correct stride and alignment, separate object lifetime, corruption defenses, concurrency choices, and efficient handling of nine-byte payloads.
Software Engineering FundamentalsOnsite - Hudson River TradingMediumSoftware EngineerExplain Virtual Memory, MMUs, and TLBs
Trace a virtual-memory load through TLB lookup, page-table walking, MMU permission checks, cache and physical access, page-fault handling, context switches, huge pages, and cross-core shootdowns.
Software Engineering FundamentalsOnsite - Hudson River TradingHardSoftware EngineerImplement Order Modification Feature
This question evaluates a software engineering competency in modifying and extending a C++ client/server trading system, focusing on state management, input validation, API integration, and maintaining invariants for order lifecycle.
Coding & AlgorithmsOnsite - IBMEasySoftware EngineerExplain CI/CD, Kubernetes delivery, and troubleshooting
This question evaluates operational DevOps and cloud-native competencies, specifically CI/CD concepts and tools, GitOps delivery with Argo CD, Kubernetes deployment and troubleshooting (including Helm and StatefulSet vs Deployment), containerization rationale, Linux process and file inspection, network diagnostics, database deployment safety, and infrastructure concepts such as HPC and VPC. It is commonly asked in Software Engineering Fundamentals and DevOps interviews to measure production-readiness, troubleshooting ability, and tooling familiarity, emphasizing practical application while requiring underlying conceptual understanding of system behavior and reliability.
Software Engineering FundamentalsOnsite - IBMEasySoftware EngineerHow would you use generative AI at work?
This question evaluates a candidate's judgment and leadership in applying generative AI tools, testing competencies in risk assessment, data confidentiality, security awareness, correctness verification, and team change management for a software engineer role.
Behavioral & LeadershipOnsite - IllumioMediumSoftware EngineerCount Regions in a Binary Grid
This problem tests your ability to navigate a 2D grid and identify connected components using graph traversal techniques like Depth-First Search (DFS) or Breadth-First Search (BFS).
Coding & AlgorithmsOnsiteDFSBFSGraph - IllumioMediumSoftware EngineerDesign Multicloud Publishing and API Gateway
This question tests the ability to design a distributed system that reliably replicates data from a primary database to multiple cloud providers while exposing a unified, secure API gateway for external consumers.
System DesignOnsiteDistributed SystemsAPI GatewayCDC - IllumioHardSoftware EngineerDesign a Time-Series Database
This problem tests the ability to architect a high-throughput, horizontally scalable system for time-series data, balancing ingest performance with efficient range-query capability.
System DesignOnsiteTime-SeriesDistributed SystemsIndexing - IllumioMediumSoftware EngineerSolve Matrix Traversal and Pair Sum
This problem tests your ability to manipulate 2D matrix indices for spiral traversal and apply efficient hash-based lookups to solve the two-sum problem within a specific sequence.
Coding & AlgorithmsOnsiteMatrixArrayHash Table - InstacartMediumSoftware EngineerAnswer standard behavioral questions
How to answer the standard behavioral and leadership questions in an Instacart Software Engineer onsite using the STAR framework. Covers tell-me-about-yourself, end-to-end ownership, high-severity incidents, conflict and disagreement, failure and learning, tight deadlines with ambiguous requirements, prioritization, influencing without authority, process improvement, and your most impactful accomplishment — each with a quantified model answer.
Behavioral & LeadershipOnsite - InstacartMediumSoftware EngineerCalculate a Basket Total from Delimited Product Records
Parse pipe-delimited shopping cart records to compute the total basket cost in integer cents, properly accumulating repeated SKUs and handling zero-quantity items.
Coding & AlgorithmsOnsitestringsparsinghash-table - InstacartMediumSoftware EngineerCompute and optimize average wait time
This question evaluates skills in scheduling and queueing algorithms, simulation of service systems, and reasoning about time and space complexity when computing average waiting times.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerCompute average customer waiting time
Compute average customer waiting time evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - InstacartMediumSoftware EngineerCompute delivery wait times
This question evaluates competence in event-driven simulation, scheduling and queueing concepts, and algorithmic analysis by requiring computation of average customer waiting time for single and multiple shoppers.
Coding & AlgorithmsOnsite - InstacartHardSoftware EngineerDesign a bus simulation metric
This problem tests your ability to design a telemetry metric for a simulation environment, requiring you to define efficiency, implement instrumentation within existing logic, and explain how to validate the metric's accuracy.
Software Engineering FundamentalsOnsiteSystem DesignInstrumentationSimulation - InstacartMediumSoftware EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDesign 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 EngineerDiscuss 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 EngineerEvaluate 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
HubSpot
Hudson River Trading
IBM
Instacart