DoorDash Software Engineer Interview Guide

At DoorDash, empowering local economies is the name of the game. The food delivery platform enables millions of orders a day around the world. Apart from its commitment to supporting local businesses, DoorDash is also a notoriously great place to work. It’s fun, fast, and growing by leaps and bounds. In fact, in 2023, it was named one of the best workplaces in America and one of Fortune’s Future 50 companies.

Since DoorDash’s platform operates through both a website and app, software engineers (SWE) are crucial to maintaining its success and driving growth. SWEs at DoorDash get to wield the newest and most innovative technologies to help carry out the company’s goals.

Ready to throw your hat in the ring for an SWE position at DoorDash? We put together this interview guide to prepare you for the interview process, which can be lengthy and competitive. Keep reading to find out about DoorDash’s hiring criteria and tips to succeed in its SWE interview.

What does a DoorDash SWE do?

Software engineering at DoorDash is broad and encompasses many areas of the company. This can mean anything from keeping DoorDash infrastructure up to date to creating new features for users or supporting new areas for expansion. In general, however, DoorDash SWEs are customer-focused, solutions-driven team players and expert communicators. They power the customer experience by prioritizing innovation at every level, and often work with product managers and other stakeholders specific to their team.

Most DoorDash SWE roles focus on maintaining the backend infrastructure that helps power its three-sided marketplace, but there are also opportunities to work on mobile and web products as well as with data and machine learning.

Junior-level SWE roles tend to focus on working with their teams to build and advance DoorDash infrastructure. Senior or managerial roles, on the other hand, help establish and lead long-term roadmaps and manage a team to effectively execute them.

According to its website, DoorDash engineers are guided by four pillars:

• Customer obsession: A dedication to improving the customer experience through every new product and feature
• Velocity at scale: Maintaining high quality, reliability, and integrity with rigorous execution
• Pragmatic solutions: Propelling unprecedented and sustainable global business growth by leveraging cutting-edge technologies
• Impact-driven culture: Solving complex real-world problems with diverse teams of helpful, humble people

DoorDash’s engineering structure is organized into five broad categories:

• Consumer experience: Owns all applications a customer would use and the back-end services that power them. Powers the shopping cart, pricing, and order processing systems.
• Dasher experience: Oversees all things as it relates to the logistics engine and focuses on the execution of deliveries, including the logistics "brain" that routes Dashers.
• Merchant experience: Leads the platform to empower businesses to connect with consumers.
• Product engineering: Owns customer-facing applications for all sides of the marketplace; some sub-teams include Marketplace, Merchant, Consumer, Logistics, Operational Excellence, New Verticals, Money, and Platform & Enterprise.
• Infrastructure, data science, and security:
  • Infrastructure: Manages the engineering platform on top of the AWS Cloud ecosystem.
  • Data Platform: Oversees the “Big Data” tech stack required for DoorDash’s large volume of data.
  • Security: Develops robust application security best practices for the security of users.

Overall, DoorDash has a startup mentality: Anyone can suggest an idea and if it’s worthwhile, it can be built.

What are the typical job requirements for a DoorDash SWE?

SWE opportunities are available at all levels, from college internships and entry-level positions to senior and managerial roles. Since job requirements, experience, and salaries for each role vary, make sure to carefully study each position’s job description to ensure you’re qualified.

Overall, candidates applying for non-internship positions should have some experience with coding languages and Big Data infrastructure and governance—whether that experience was acquired through schooling or previous jobs.

Besides technical skills, candidates are also expected to embody DoorDash’s mission values. Familiarity with DoorDash’s tech stack (including REST APIs, various databases, Docker, etc) is a huge plus.

Here are a few SWE positions to help you get a sense of what DoorDash is looking for:

Software Engineer II, data governance platform (entry- to mid-level)

• BS, MS or PhD in computer science or equivalent
• 2+ years of experience with CS fundamental concepts and experience with at least one of the programming languages of Scala, Java, and Python.
• Prior technical experience in Big Data infrastructure & governance – you've built meaningful pieces of data infrastructure. Bonus if those were open-sourced technologies like DataHub, Spark, Airflow, Kafka, Flink.
• Experience improving efficiency, scalability, and stability of data platforms
• Salary: $140,100-$210,100

Engineering Manager, search platform

• B.S. or M.S. in computer science or equivalent
• 10+ years of industry experience
• At least 2 years of leadership experience
• Prior experience building highly available, scalable, and reliable distributed systems
• Strong communication skills and hands-on experience working with cross-functional stakeholders
• Ability to guide and grow an excellent engineering team in a rapidly changing business environment
• Experience with search/information retrieval domain or stateful distributed systems like storage is a big plus
• Salary: $201,900-$302,900

Recommendations before you apply for DoorDash SWE roles

DoorDash prioritizes diversity, equity, and inclusion in its workplace culture and takes its values seriously. To that end, interviewers pay close attention to your experience and ability to do the job as well as your compatibility with company culture.

Make sure to browse DoorDash’s website to get a sense of what it’s like to work there. Here is a brief overview of what DoorDash looks for in candidates based on its mission and values:

• Leadership: The company values a candidate’s ability to solve problems with optimism and carry out a plan, no matter how small. It also values self-starters with big, innovative ideas and game plans for how to execute them well.
• Doers: In the fast-paced world of tech, there’s no time for dilly-dallying around your ideas. Act with urgency and precision to make those ideas a reality.
• Learners: DoorDash’s innovative teams are constantly asking questions and rethinking assumptions to improve customer service.
• Team-based: DoorDash believes that diversity fosters innovation. That’s why it’s committed to inclusivity and empowerment of every voice at the table.

Before applying for a SWE role, you should also consider the following:

• Get to know the different hiring teams at DoorDash. The role you’re applying for could fall under any team from marketplace to data science. You don’t have to know these teams front to back, but it helps to gain some familiarity ahead of time. You can learn more about each team through DoorDash’s engineering website.
• Revamp your resume. SWEs interact across several departments and cross-functional teams at DoorDash, so clear communication skills are highly valued. Your resume is the perfect way to demonstrate those skills from the very beginning. Tell a coherent, compelling story around the experiences listed on your resume, and why you’re an ideal candidate.
• Practice with mock interviews. Exponent's coaching services are your best friend. Don’t limit your pool of mock partners to other SWEs and peers in tech—grab a non-tech friend and describe the most recent project you worked on.
• Lean on your community. Find a few DoorDash SWEs on LinkedIn or through Exponent and ask them about their experiences. Since they’ve gone through what you’re going through now, they’re great sources of information and support.

Interview Process

DoorDash’s SWE interview process varies based on your background and the seniority level of the role you’re applying for. For recent graduates, it generally consists of three stages:

• An online assessment with 2 medium- to hard-level LeetCode-style questions on HackerRank
• A coding assessment made up of 2 back-to-back technical interviews
• A behavioral interview with a manager or engineer

More experienced candidates applying for mid-level and senior roles can expect a somewhat more intensive interview process. It includes:

• A 30-minute phone screen with a recruiter
• A 60-minute technical screen on HackerRank
• A virtual interview loop with 2-4 sessions covering behavioral questions, system design, domain knowledge, and coding

No matter what, your interviewer will be a SWE at a similar or higher level than the role you’re applying for. The interview process generally takes place over a week.

Recruiter Phone Screen

For experienced candidates, the first stage of the interview process is a 30-minute call with a DoorDash recruiter. While the recruiter may ask a few behavioral questions, these calls are less evaluative and more about leveling expectations and gauging your motivation and background.

The recruiter will review your resume and ask questions about your experience and why you want to work at DoorDash. They’ll also tell you about what to expect from the next steps of the interview process. Make sure to ask the recruiter any questions you have about future interview formats.

Here are a few questions you can expect:

Technical Screen

Next, you’ll do a 60-minute virtual interview with a DoorDash SWE for the technical screen. Interviewers use this session to gauge your thought process, problem-solving ability, and communication skills. Recent grads generally go through two of these technical rounds back to back, while experienced candidates only go through one.

The interview is conducted through a coding platform like HackerRank or CodeSandbox. You’ll get a few problems similar to those you might encounter in your day-to-day work as a SWE at DoorDash and be expected to talk through your problem-solving process.

At the beginning of the interview, the interviewer will introduce themselves and the team they work with at DoorDash. You will have the opportunity to ask questions at the end of the session.

DoorDash offers detailed interview prep tips for its technical rounds according to the different teams you may be applying for as a SWE:

• Management
• iOS
• Web
• Backend
• Android

Interviewers use a scorecard to evaluate candidates and look for specific signals for different sections. According to a DoorDash SWE who’s also interviewed candidates, it’s possible to fail a technical interview even if you arrive at the perfect solution. That’s often because of failing to communicate or show you can think through a problem.

Checking off the boxes will give you a passing score but, depending on the competitiveness of the opening, passing may not be enough to move to the next round and may result in down-leveling or being called back for additional rounds.

Virtual Interview Loop

After the technical screen is the virtual interview loop, which consists of 3-4 rounds. Each session runs 60-75 minutes, with 15-minute breaks in between them. You’ll encounter coding, systems design, domain knowledge, and behavioral questions.

System Design and Domain Knowledge

The system design and domain knowledge sessions (about 75 minutes altogether) may be conducted separately or in the same session depending on your skill level. You won’t be asked to code during this session, but you’ll be verbally evaluated for your technical knowledge and communication skills.

System Design

After being given a problem or design, begin by asking clarifying questions on technical or functional requirements. The interviewer is not looking for any specific answer, but asking questions will help you arrive at one of them.

Next, start your design. You will be given a virtual whiteboard tool during the interview to help visualize or diagram and make calculations. Begin with a high-level outline, and then go through different components piece by piece.

Interviewers expect candidates to develop a high-level design within the first 20-25 minutes.

As you’re working through this section, consider addressing the following questions:

• How can you tell if the system is working?
• Are there any bottlenecks in the design?
• How do the components work together?
• How will the system scale?

Next, provide justifications for the design. Explain why you think your design is optimal, as well as any trade-offs you are considering. Don’t be afraid to continue developing or changing the direction of your design in real time—this helps illustrate your thought process.

Finally, describe the properties of your solution. During the discussion, try to address:

• General operation patterns of the system
• Reliability and scalability
• Production quality concerns
• What metrics would you monitor
• How you would execute this design
• Observability

Sample questions include:

Domain Knowledge

If the interviewers choose to separate system design from domain knowledge, a dedicated domain knowledge round will focus on assessing your previous experience. You'll be asked to walk the interviewer through a previous project and describe why it worked—or didn’t.

It’s okay to describe a project that didn't work out. DoorDash wants candidates who can draw key lessons from their past experiences. That includes both failures and successes.

This interview will evaluate:

• Your role on the team or project: What did you do? How did your role impact the outcome?
• Why was the project prioritized? What would happen if the outcome did not meet expectations?
• How was it built? What alternatives did you consider? What was cross-functional collaboration like?
• What was the outcome? How did you and the team measure success? What would you do differently?

Coding

The coding round consists of two 60-minute sessions that are similar to the earlier technical screen. Interviewers pay close attention not only to your coding and problem-solving abilities but also to how you communicate your processes.

According to a DoorDash SWE and interviewer, there are some specific algorithms and data structures candidates must be familiar with. These include:

• Graphs
• Stacks and queues
• Lists
• Sets
• Arrays
• Hash maps
• Heaps

It also helps to be well-versed in the following algorithms:

• Linked lists
• Recursion
• Search and sort

To prepare, consider practicing medium- and hard-level coding questions on Exponent about algorithms, data structures, and object-oriented categories.

Here are some more coding tips for this session directly from DoorDash’s engineering team:

• Discuss design tradeoffs and good abstractions with your interviewer.
• Write simple code with correct syntax.
• Use whatever methodology you are most comfortable with and present your knowledge in the best way.
• Find and fix bugs, consider testability, and discuss this throughout the coding process.

Effective and clear communication skills are a crucial part of these interviews. Thinking out loud and keeping your interviewer engaged in your thought process helps give them a sense of your problem-solving skills and ability to work with others. At the same time, it’s okay to take a few moments of silence to think about your strategy before you begin.

Talking while coding can be difficult and distracting. An interviewer won’t expect you to do this, but here are some ways you can keep them involved:

• Ask clarifying questions after being given a problem.
• Explain your high-level approach to solving the problem before you begin coding.
• Identify potential flaws or tradeoffs in your approach when you see them.
• Indicate when/if you change your direction to a new approach.
• Listen to the interviewer’s feedback, as they are there to help guide you.

Behavioral

The final round in the onsite interview loop is a 60-minute behavioral interview with a manager or SWE. The conversation will cover behavioral questions related to DoorDash’s mission values and how you would fit into the specific team you’re applying to.

DoorDash’s values inform everything the company does. For that reason, make sure to familiarize yourself with DoorDash’s mission values and engineering teams ahead of time.

Be prepared to some examples of how you exemplify those values—like a time when you led a team on a big project or took a risk to pursue something new, even if you failed.

You don’t need to know everything about DoorDash, but you should at least show interest and optimism in working for the company. In fact, one of the biggest mistakes a candidate can make is to fail to show interest in the company.

One of DoorDash’s unique policies mandates that all employees do four deliveries per year as Dashers. This allows the team to see firsthand how the product works. Interviewees who seem disinterested in the company or turned off by the idea of making deliveries as Dashers are viewed as poor candidates.

DoorDash also values diversity and inclusion, with the philosophy that diversity breeds innovation. Take the time to browse DoorDash’s efforts at cultivating a more inclusive environment within the company and in the communities it serves, and think about how you would contribute to this environment.

Sample questions include:

How to prepare

Unlike the previous interviews for the SWE role, the behavioral interview is entirely verbal. Interviewers will evaluate your likelihood of fitting in with a team based on your values, teamwork capabilities, and leadership skills.

It’s easy to get lost in an answer. One way to prepare for these questions is to dump your resume into a spreadsheet and create a STAR-based story around each point. This framework helps you clearly tell stories about your past experiences. Make sure you’ll be able to address questions about your weaknesses, interpersonal skills, and what you’ve learned from failures.

You’ll face “tell me about a time when” questions in this section. Come prepared for these with specific examples of your past product successes that exemplify your ability to tackle large, complex projects. Don’t forget to mention experience with cross-functional collaboration, as this is a big part of the job at DoorDash.

Tips and Strategies

• Get familiar with DoorDash’s mission and values. Then incorporate them into your answers as much as possible. DoorDash takes pride in its award-winning workplace and commitment to equity and diversity. Keep an eye on its blog to familiarize yourself with what it’s like to work there. It also looks for candidates who embody its mission of “connecting people with possibilities.” Don’t be shy in showing your interest in and enthusiasm for DoorDash’s mission.
• Get plugged into DoorDash’s engineering site. The Engineering team at DoorDash values transparency to help advance innovation throughout the industry. Read the engineering blog or subscribe to its newsletter for updates on the latest innovative projects and advancements from the team. This website is full of information that will help you understand what working at DoorDash is like and will inform your conversations with interviewers.
• Maintain communication with your interviewer during coding sessions. Thinking out loud while working through a design helps your interviewer evaluate your communication skills during the coding interviews. Describe your actions throughout the process by using phrases like “I’ll start by doing X…” or “I’m modifying my approach here because…”

Additional Resources

• DoorDash’s Engineering website
• Exponent’s Software Engineering Interview Course
• DoorDash Interview Question Database
• How to Prepare for a Technical Interview at DoorDash