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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 1951–1980 of 5874 results
- DoorDashMediumSoftware EngineerDesign a Review and Rating System for Food Delivery Menu Items
Design a review and rating system for a food-delivery platform, where customers review the individual menu items they received and every menu shows each item's rating. It tests data modeling, purchase verification, incremental rating aggregation, caching for read-heavy menus, moderation, and handling bursts on popular items.
System DesignOnsite - DoorDashMediumSoftware EngineerDesign a Sliding-Hour Top-Restaurants Service
This problem tests the ability to design a high-throughput, real-time analytics system that maintains a top-k leaderboard over a sliding time window.
System DesignOnsiteStreamingAnalyticsDistributed Systems - DoorDashMediumSoftware EngineerDesign a Store Recommendation System and Explain ML Trade-offs
Design a personalized store recommendation feed for an on-demand delivery platform and evaluate key machine learning modeling trade-offs.
ML System DesignOnsiteRecommendation SystemsMulti-Task LearningRanking - DoorDashHardSoftware EngineerDesign a distributed cron job scheduler
Design a distributed cron job scheduler evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnsite - DoorDashMediumSoftware EngineerDesign a donations service with 3-day rolling totals
This question evaluates a candidate's competency in designing scalable, low-latency streaming data systems, covering event-time windowing, rolling-window aggregation, idempotency for duplicate events, late/out-of-order handling, and auditability.
System DesignOnsite - DoorDashMediumSoftware EngineerDesign a hierarchical path registry
Design a hierarchical path registry 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 - DoorDashMediumSoftware EngineerDesign a multi-channel notification system
This System Design question evaluates distributed-systems and API-design skills—scalability, reliable fanout, multi-channel integration, delivery guarantees (retries, idempotency, deduplication), rate-limiting, subscription/preferences modeling, and observability.
System DesignOnline Assessment - DoorDashHardSoftware EngineerDesign a notification system
This question evaluates a candidate's competency in designing scalable, reliable multi-channel notification platforms, covering distributed systems, multitenancy, API and storage schema design, queuing and retry strategies, rate limiting, observability, localization, A/B testing, and compliance considerations like GDPR.
System DesignTechnical Screen - DoorDashMediumSoftware EngineerDesign a resilient bootstrap API
This question evaluates skills in resilient API aggregation, fault-tolerant microservice orchestration, and reliability engineering, focusing on defining API contract semantics and handling partial failures at the architectural/system-design level (service-to-service abstraction); category/domain: System Design.
System DesignTechnical Screen - DoorDashHardSoftware EngineerDesign a resilient dasher payment system
A DoorDash software-engineer system-design interview question: design a resilient Dasher payment system that computes payouts from order lifecycle events (accept/fulfill/cancel). It spans event-driven ingestion, idempotency and exactly-once-vs-at-least-once semantics, data modeling for high write throughput and per-dasher pay-period queries, timezone/DST handling, detection and remediation of missing or out-of-order data, batch-vs-streaming reconciliation, reliability, and consistency trade-offs.
System DesignTechnical Screen - DoorDashHardSoftware EngineerDesign a scalable Instagram-like platform
Design a scalable Instagram-like platform evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - DoorDashHardSoftware EngineerDesign a service aggregator with robust error handling
Design a service aggregator with robust error handling evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - DoorDashMediumSoftware EngineerDesign a single-machine LRU cache
This question evaluates a candidate's ability to design an efficient in-memory LRU cache and apply concurrency control, covering eviction semantics, capacity management, key updates, and synchronization for thread safety.
Coding & AlgorithmsTechnical Screen - DoorDashMediumSoftware EngineerDesign an API for pay computation with retries
Assesses the candidate's ability to design robust HTTP APIs covering endpoint modeling, request/response schemas, datetime formats, idempotency strategies, retry semantics, validation/error codes, and observability for pay-computation services.
Software Engineering FundamentalsOnline Assessment - DoorDashMediumSoftware EngineerDesign an Alert Notification Service for Downstream Consumers
Design a reliable, scalable alert and event notification delivery platform that decouples upstream producers from heterogeneous downstream consumers with independent fan-out, isolation, retries, and dead-letter handling.
System DesignTechnical ScreenDistributed SystemsMessage QueuesEvent-Driven - DoorDashHardSoftware EngineerDesign an Online Course Marketplace Review System Schema
Design the review and rating feature of an online course marketplace where only learners who completed a course may rate it, with the discussion centered on table design, keys, constraints, and the indexes each read path needs.
System DesignOnsitesystem-designdatabase-designschema - DoorDashHardSoftware EngineerDesign an async donation payment platform
This question evaluates a candidate's ability to design scalable, reliable payment systems and asynchronous processing pipelines, covering competencies in distributed systems, idempotency, data modeling, security/PCI compliance, retry and dead-letter strategies, and observability.
System DesignOnsite - DoorDashHardSoftware EngineerDesign consistent hashing for sharding
This question evaluates understanding of consistent hashing, replica placement, dynamic membership, weighted load distribution, rebalancing impact, and related distributed-systems competencies for routing and sharding.
System DesignOnsite - DoorDashMediumSoftware EngineerDesign consistent hashing with a sorted map
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 consistent hashing with a sorted map states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - DoorDashMediumSoftware EngineerDesign dasher-to-order assignment algorithm
This question evaluates a candidate's skills in real-time algorithm design and systems thinking for dynamic matching and optimization, including scalability, time/space complexity analysis, and handling partial or delayed information.
Coding & AlgorithmsOnsite - DoorDashMediumSoftware EngineerDesign dynamic connectivity with alive nodes
This question evaluates understanding of dynamic graph data structures, connectivity algorithms, state management for node activation/deactivation, complexity analysis, and concurrent operation considerations.
Coding & AlgorithmsOnsite - DoorDashMediumSoftware EngineerDesign hierarchical path store with create/set/get/remove
This question evaluates a candidate's competency in hierarchical data structures, path parsing, API semantics, error signaling, complexity analysis, and unit testing for implementing a UNIX-style key-value path store.
Coding & AlgorithmsTechnical Screen - DoorDashHardSoftware EngineerDesign limited-time donation platform
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 limited-time donation platform states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - DoorDashHardSoftware EngineerDesign notification and project architecture
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 notification and project architecture states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignTechnical Screen - DoorDashHardSoftware EngineerDesign review system with voting and rewards
This system design question evaluates a candidate's ability to architect a scalable review platform with voting, counter aggregation, and rewards at high traffic volumes. It tests practical knowledge of distributed counter strategies, idempotent write handling, read/write path separation, and abuse prevention — core competencies assessed in senior software engineer interviews.
System DesignOnsite - DoorDashMediumSoftware EngineerDetermine equality after limited swaps
This question evaluates string manipulation and combinatorial reasoning about character swaps and anagram formation, focusing on competencies such as frequency analysis and reasoning about minimal edit operations.
Coding & AlgorithmsTechnical Screen - DoorDashMediumSoftware EngineerDiscuss Projects and Planning Improvements
This question evaluates ownership, product understanding, end-to-end project leadership, cross-functional collaboration, and the ability to quantify impact within behavioral and leadership competencies for software engineers.
Behavioral & LeadershipTechnical Screen - DoorDashMediumSoftware EngineerDiscuss feedback, help, and conflict
This question evaluates interpersonal and leadership competencies such as receiving and acting on constructive feedback, mentoring or helping colleagues, and managing conflict within engineering teams (Behavioral & Leadership).
Behavioral & LeadershipTechnical Screen - DoorDashMediumSoftware EngineerDiscuss project experience and teamwork
Discuss project experience and teamwork evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipOnsite - DoorDashMediumSoftware EngineerExplain AI Tool Use, Model Selection, and Engineering Validation
Explain practical AI use across coding and summaries, with honest contribution measures, task-specific model choices, validation, and cost awareness.
Behavioral & LeadershipOnsite
DoorDash