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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 1981–2010 of 5874 results
- DoorDashMediumSoftware EngineerExplain Performance, OKRs, Failure, and Project Learning
This question tests your ability to navigate complex project lifecycles by evaluating your ownership of OKRs, your response to significant failure, and your capacity for introspective learning.
Behavioral & LeadershipOnsiteLeadershipOKRsBehavioral - DoorDashMediumSoftware EngineerExplain Project Impact from Prototype to Shared Ownership
Describe a proud project's impact, evidence of time saved, transition from prototype to supported use, and cross-functional ownership.
Behavioral & LeadershipOnsite - DoorDashHardSoftware EngineerExplain Why You Are Changing Roles
This question tests your ability to articulate a clear career trajectory, demonstrating that your move is driven by professional growth rather than dissatisfaction with your current situation.
Behavioral & LeadershipOnsiteCareer StrategyCommunicationProfessionalism - DoorDashMediumSoftware EngineerExplain a Project's Most Complex Technical Component in Depth
Explain a project's most complex technical component through its invariants, design alternatives, implementation details, and failure-case validation.
Software Engineering FundamentalsOnsite - DoorDashHardSoftware EngineerExplain an AI-Assisted Project
Tests your ability to articulate the engineering realities of an AI- or LLM-driven project, focusing on rigorous evaluation, production guardrails, failure modes, and personal ownership rather than high-level buzzwords.
Behavioral & LeadershipOnsiteBehavioralAI & MLSystem Reliability - DoorDashHardSoftware EngineerExplain conflict resolution and growth
This question evaluates collaboration, ownership, technical leadership, conflict resolution, incident management, decision-making, and the ability to learn from and prevent mistakes.
Behavioral & LeadershipOnsite - DoorDashMediumSoftware EngineerExplain handling conflicts and learning from mistakes
This interview question evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer for Explain handling conflicts and learning from mistakes states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipOnsite - DoorDashMediumSoftware EngineerFilter Open Restaurants Through Existing Domain APIs
Implement an orchestrator service that coordinates calls to a directory API and an operating-hours API with bounded concurrency, short-circuit filtering, resilient error handling, and in-memory caching.
Software Engineering FundamentalsTechnical Screenconcurrencycachingsystem-integration - DoorDashMediumSoftware EngineerFind Each Cell's Nearest Source
This question evaluates understanding of shortest-path computation and distance labeling in grid-based graphs, measuring competency in algorithmic problem solving and efficient traversal strategies.
Coding & AlgorithmsOnsite - DoorDashHardSoftware EngineerFind longest common ordered restaurant list
This question evaluates a candidate's understanding of sequence algorithms, dynamic programming, and string/list manipulation by requiring computation of the longest common subsequence between two ordered lists of restaurant IDs.
Coding & AlgorithmsOnsite - DoorDashMediumSoftware EngineerFind names similar by one swap
This question evaluates string manipulation, character-frequency analysis, and algorithmic reasoning to determine near-matches under a single-character-swap constraint.
Coding & AlgorithmsTechnical Screen - DoorDashMediumSoftware EngineerFind the Minimum Delivery Processing Speed
This problem tests binary search on the answer space to find the minimum throughput capacity required to process a set of delivery orders within a fixed deadline.
Coding & AlgorithmsOnsiteBinary SearchOptimizationMath - DoorDashMediumSoftware EngineerFind the Minimum Parenthesis Deletions and Their Positions
This problem tests string manipulation, stack-based parsing, and greedy logic to identify the indices of parentheses that must be removed to transform a string into a valid sequence.
Coding & AlgorithmsOnsiteStringsStackGreedy - DoorDashMediumSoftware EngineerFix a Round-Robin Load Balancer, Then Implement Consistent Hashing
A debugging-style coding round on request routing: make a round-robin load balancer behave correctly as servers join and leave, then implement consistent hashing so requests with the same key stay on the same server. It tests careful state handling, concurrency, edge cases such as an empty pool, and reasoning about how many keys move when membership changes.
Software Engineering FundamentalsOnsite - DoorDashMediumSoftware EngineerGenerate the next lexicographic array arrangement
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Generate the next lexicographic array arrangement states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - DoorDashHardSoftware EngineerHandle a payment-service incident with resource spikes
Handle a payment-service incident with resource spikes 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 & LeadershipTechnical Screen - DoorDashEasySoftware EngineerHandle payment-service outages
This question evaluates a candidate's competence in designing fault-tolerant payment workflows and operational resilience, covering concepts such as idempotency, retry strategies, queuing and dead-letter handling, circuit breaking, reconciliation, and monitoring.
Software Engineering FundamentalsOnsite - DoorDashMediumSoftware EngineerHandling Duplicate Upstream Order Records in Dasher Pay Calculation
Explain how a Dasher pay calculation driven by upstream order records stays correct when those records contain duplicates. Tests deciding when two records describe the same fact, making processing safe against replayed records, handling conflicting and late data or corrections after payout, and preventing double payouts.
System DesignTechnical Screen - DoorDashEasySoftware EngineerHow do you discuss mistakes and trade-offs?
This question evaluates competency in accountability, leadership, incident management, and product/operational decision-making within the Behavioral & Leadership domain for software engineers.
Behavioral & LeadershipOnsite - DoorDashHardSoftware EngineerHow to prepare for AI-assisted coding interviews?
Tests your ability to critically evaluate, debug, and refactor AI-generated code for a real-time order batching service under concurrent access, edge-case constraints, and strict correctness requirements.
Software Engineering FundamentalsOnsiteconcurrencysystem-designrefactoring - DoorDashMediumSoftware EngineerIdentify members lacking specialty coverage
Identify members lacking specialty coverage 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 - DoorDashHardSoftware EngineerImplement Bootstrap-like responsive utility classes
This question evaluates proficiency in front-end engineering, including CSS utility system design, responsive grid layout, semantic HTML, accessibility (ARIA and focus management), form validation, asynchronous submission patterns, and lightweight JavaScript for interactivity and telemetry.
Software Engineering FundamentalsOnsite - DoorDashMediumSoftware EngineerImplement Timeout Refund Workflow
Design and implement a stateful, idempotent refund workflow manager that safely handles gateway timeouts, retries, and duplicate requests.
Coding & AlgorithmsOnsiteState MachineIdempotencySystem Design - DoorDashMediumSoftware EngineerImplement a Consistent Hash Ring
This problem tests your ability to implement a distributed hashing mechanism that minimizes data movement when adding or removing nodes.
Software Engineering FundamentalsOnsiteHashingDistributed SystemsData Structures - DoorDashMediumSoftware EngineerImplement a Resilient Aggregator over Three Services
Implement an asynchronous aggregation service that orchestrates calls to User, Payment, and Address downstream clients with dependency-aware concurrency, partial failure handling, and deadline enforcement.
Software Engineering FundamentalsOnsiteConcurrencyAsyncIOAPI Design - DoorDashEasySoftware EngineerImplement a consistent hashing ring
This question evaluates understanding of consistent hashing, virtual nodes, deterministic hash functions, and data structure design for efficient key-to-server mapping and dynamic membership changes.
Coding & AlgorithmsOnsite - DoorDashMediumSoftware EngineerImplement a hierarchical key-value store
Implement a hierarchical key-value store 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 & AlgorithmsTechnical Screen - DoorDashMediumSoftware EngineerImplement a simple service with tests
Implement a simple service with tests 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 EngineerImplement and compare round-robin and consistent hashing
This question evaluates a candidate's ability to implement and reason about load balancing algorithms (round-robin and consistent hashing), covering competencies in data structures, hashing, concurrency, correctness, and unit testing.
Coding & AlgorithmsOnsite - DoorDashMediumSoftware EngineerImplement consistent hashing ring
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Implement consistent hashing ring states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen
DoorDash