DoorDash Software Engineer interview questions

265 Software Engineers have shared notes from their DoorDash interviews, with the questions they were asked in each round. That is 64% of the 416 DoorDash interview notes on Screna AI.

265 Software Engineer interview notes

DoorDash·Software Engineer·Onsite - Multi Round

Aug 2026
Prepping for a Doordash virtual onsite as a software engineer and one of the four rounds is something called an AI Code Craft round where you use your own machine and AI tools while screen sharing. Mostly just trying to figure out what to expect before going in.
  • In Doordash's AI Code Craft round, are candidates expected to have paid AI subscriptions, and what happens if you hit a free-tier usage limit mid-interview?

“This is what's keeping me up.”

View Post

DoorDash·Software Engineer·Technical Phone Screen

Jul 2026
DoorDash software engineer round, one algorithmic problem the whole time. Pretty standard multi-source BFS setup but the edge case around empty grids tripped me up a bit.
  • Given a grid of 0s and 1s where 1s are source cells, return a same-sized matrix where each cell contains its shortest distance (4-directional) to the nearest source cell. Source cells have distance 0. If no source cells exist, every cell should return -1.

“I knew it was BFS pretty fast, the multi-source part clicked quickly too.”

View Post

DoorDash·Software Engineer·Onsite - System Design / Architecture

Jul 2026
System design round at DoorDash for a software engineer role. The whole thing was basically one big consistent hashing problem and they wanted a lot of depth on it, not just the concept but actual implementation decisions.
  • Design and implement a consistent hashing system that distributes keys across a dynamic set of backend nodes, including API design, virtual nodes, hash function selection, and handling node additions and removals with minimal key movement.

“This was a meaty one.”

View Post

DoorDash·Software Engineer·Technical Phone Screen

Jul 2026
DoorDash coding screen for a software engineering role. One problem, delivery event processing, and it was more involved than it looked at first glance.
  • You're given a list of delivery event records for a single dasher, each with an order ID, an event type (one of CREATED, ACCEPTED, PICKED_UP, DELIVERED, or CANCELED), and a timestamp string that may include timezone info and may not be sorted. Compute the dasher's total pay given a rate per minute, where an order is active from ACCEPTED until DELIVERED or CANCELED, rounding down to whole minutes. Handle malformed sequences explicitly.

“The problem sounds like a simple loop until you realize the timestamps aren't sorted and might have timezone offsets.”

View Post

DoorDash·Software Engineer·Onsite - System Design / Architecture

Jul 2026
DoorDash system design round, one big question about state management that sprawled into basically every frontend architecture topic imaginable. Felt like they wanted to see if I could hold a coherent opinion across ten different sub-problems at once rather than just recite library docs.
  • Compare Redux with modern frontend state and data management approaches, and design an end-to-end strategy for a React SPA that needs to consume multiple APIs, support offline viewing, pagination, optimistic updates, and error retries.

“This question is massive and they absolutely know it.”

View Post

DoorDash·Software Engineer·Technical Phone Screen

Jul 2026
DoorDash software engineering interview with a meaty system design coding question. The problem was a custom hierarchical key-value store built on UNIX-style paths, which sounds manageable until you realize how many edge cases they actually want you to cover.
  • Design and implement a hierarchical key-value store that operates on UNIX-style absolute paths, supporting create, set, get, and remove operations. Each operation has specific failure conditions: create fails if the parent doesn't exist or the path already exists, set fails on missing paths, and remove fails if the node has children. You need to choose your return types, define path syntax assumptions, justify your data structure choices, analyze complexity, and write unit tests covering edge cases.

“This was a lot to hold in your head at once.”

View Post

DoorDash·Software Engineer·Technical Phone Screen

Jul 2026
DoorDash coding round for a software engineer role. Three-part exercise: implement a small service class from a spec, extend it with a new requirement, then write unit tests covering the full thing. Felt more like a take-home in spirit even though it was live.
  • Given a written spec for a small service class with no external dependencies, implement the core logic using if/else control flow and proper input validation. State your assumptions explicitly.
  • Extend the class you just implemented to handle an additional requirement based on assumptions you clarify with the interviewer.
  • Write unit tests for both parts of the implementation, covering happy paths, edge cases, and error handling.

“The spec was short but I still managed to overthink the input validation part.”

View Post

DoorDash·Software Engineer·Onsite - System Design / Architecture

Jul 2026
System design round at DoorDash focused entirely on a donation platform problem. It was one of the more sprawling prompts I've seen, covering everything from payment idempotency to GDPR compliance to counter consistency, all in one session.
  • Design an online donation platform built around short 3-day campaigns. Walk through functional requirements, non-functional goals, and traffic estimates before getting into the architecture.
  • What APIs and data models would you define for this system? Think about entities like Campaign, Donation, Donor, PaymentIntent, and Receipt.
  • How would you handle payment processing, including idempotency, retry logic, and reconciliation with the payment provider?
  • How would you approach fraud and abuse mitigation on a platform like this?
  • What consistency model would you use for real-time donation totals, and how do you handle the traffic spikes at campaign launch and close?
  • How would you design the system to comply with PCI, handle PII, and meet CCPA/GDPR requirements?
  • How would you observe this system in production, handle disaster recovery, and backfill data if something goes wrong?
  • How would you extend this platform to support recurring donations or corporate matching programs?

“I spent too long on the requirements phase and the interviewer had to nudge me to move on.”

View Post

DoorDash·Software Engineer·Onsite - System Design / Architecture

Jul 2026
DoorDash system design round focused entirely on building a real-time driver assignment system from scratch. Pretty intense scope for a single session, covering everything from objectives and constraints to algorithms and failure modes.
  • Design a real-time system that assigns delivery drivers to incoming orders. Walk through your objectives, constraints, data structures, algorithm choices, and how you'd handle scale and partial information.

“This one sprawled fast.”

View Post

DoorDash·Software Engineer·Onsite - Behavioral / Leadership

Jul 2026
Behavioral round at DoorDash for a software engineer role, two questions, both pretty standard conflict and impact territory. Nothing shocking but you really do need a tight story ready or you'll ramble.
  • Describe a time you had a conflict with a teammate, whether over design decisions, priorities, or code quality. How did you navigate it and what happened?
  • Tell me about a project you're proud of. What was your specific contribution, what trade-offs did you face, and how did you know it made an impact?

“I went with a code review disagreement story and structured it as situation-action-result.”

View Post