Scale Engineer

Software Engineer

Software EngineerE5Hard

The DoorDash E5 Software Engineer interview process is designed to assess a candidate's technical expertise, problem-solving abilities, system design skills, and cultural fit. It typically involves multiple rounds, including technical interviews, a system design interview, and a behavioral interview. The process aims to identify engineers who can tackle complex challenges, contribute to scalable solutions, and thrive in a fast-paced, collaborative environment.

Rounds·4

Timeline·~4d

Experience·5 - 10 yrs

Comp band·US$170000 - US$220000

Interview time·180 min

Evaluation

What they measure.

  • Problem-solving skills: Ability to break down complex problems into smaller, manageable parts.
  • Algorithmic thinking: Proficiency in choosing and implementing appropriate data structures and algorithms.
  • Coding proficiency: Writing clean, efficient, and well-tested code.
  • System design: Ability to design scalable, reliable, and maintainable systems.
  • Technical communication: Clearly articulating technical concepts and solutions.
  • Collaboration: Working effectively with others and contributing to team success.
  • Behavioral aspects: Demonstrating DoorDash's core values and a growth mindset.

Preparation

How to prepare.

Tips

  1. Review fundamental computer science concepts, including data structures and algorithms.
  2. Practice coding problems on platforms like LeetCode, HackerRank, or AlgoExpert, focusing on medium to hard difficulty.
  3. Study system design principles and common architectural patterns (e.g., load balancing, caching, databases, message queues).
  4. Prepare for behavioral questions by reflecting on past experiences using the STAR method (Situation, Task, Action, Result).
  5. Research DoorDash's business, products, and engineering challenges.
  6. Understand the company's core values and how your experiences align with them.
  7. Prepare thoughtful questions to ask the interviewer about the role, team, and company culture.

Study plan

Fig · Study plan — 04 phases

01 / 04
01

Phase 01 of 04

Data Structures and Algorithms

Weeks 1-2: DSA fundamentals and practice (2-3 problems/day).

Weeks 1-2: Focus on Data Structures and Algorithms. Cover arrays, linked lists, trees, graphs, hash tables, heaps, and sorting/searching algorithms. Practice implementing these and analyzing their time and space complexity. Aim for 2-3 coding problems per day.

Questions

Commonly asked.

  • Given an array of integers, find the contiguous subarray with the largest sum.
  • Design a system to track the real-time location of delivery drivers.
  • How would you implement a rate limiter for an API?
  • Describe a time you had to deal with a production outage. What did you do?
  • Explain the difference between a process and a thread.
  • Design a distributed cache system.
  • Tell me about a challenging project you worked on and how you overcame obstacles.
  • How do you ensure the scalability of your code?
  • What are the trade-offs between SQL and NoSQL databases?
  • Describe your experience with asynchronous programming.

Locations

Regional differences.

Fig · Regions — 03 locations

01 / 03

Location

San Francisco Bay Area

Interview focus

Deep dive into distributed systems and microservices architecture.Emphasis on scalability, reliability, and performance of solutions.Understanding of cloud-native technologies (AWS, Kubernetes).Experience with data pipelines and large-scale data processing.Strong problem-solving and debugging skills in a distributed environment.

Common questions

  • How would you design a real-time notification system for DoorDash deliveries?
  • Discuss a challenging technical problem you solved at scale.
  • Explain your experience with distributed systems and microservices.
  • How do you approach debugging complex production issues?
  • Describe a time you had to influence a technical decision within your team.

Tips

  • Familiarize yourself with common distributed system patterns.
  • Prepare to discuss your experience with cloud platforms.
  • Be ready to whiteboard complex system designs.
  • Highlight contributions to open-source projects if applicable.
  • Understand DoorDash's tech stack and challenges.

Rounds

Round-by-round.

Expand a step for evaluation criteria, sample questions, and prep notes.

Med

Technical Interview (Coding) · 45 min · Software Engineer

This round focuses on your ability to solve coding problems using data structures and algorithms. You will be presented with one or two coding challenges and expected to write code on a shared editor. The interviewer will assess your problem-solving approach, coding style, and understanding of algorithmic concepts. They will also probe into the efficiency and correctness of your solution.

What they look for

A structured approach to problem-solving.Clean, readable, and efficient code.Ability to identify and discuss time/space complexity.Consideration of edge cases and constraints.

Evaluation

  • Problem-solving approach
  • Coding proficiency
  • Understanding of data structures and algorithms
  • Time and space complexity analysis

Sample questions

  • Given a binary tree, invert the tree.

    TreeRecursionBinary Tree

  • Find the kth largest element in an unsorted array.

    ArraySortingHeapQuickSelect

  • Implement a function to check if a string is a palindrome.

    StringTwo Pointers

Prep for this round

  1. 01Practice coding problems regularly.
  2. 02Focus on understanding the underlying algorithms and data structures.
  3. 03Be prepared to explain your thought process step-by-step.
  4. 04Write clean, well-commented code.
  5. 05Test your code with various inputs, including edge cases.

Common rejection reasons

  • ×Inability to articulate thought process clearly.
  • ×Poor coding practices (e.g., inefficient code, lack of error handling).
  • ×Failure to consider edge cases or constraints.
  • ×Lack of understanding of fundamental data structures and algorithms.

DSA

Coding questions at DoorDash.

Frequently reported on DoorDash loops

View all at DoorDash

Other guides

More at DoorDash.