# Software Engineer
**Role:** Software Engineer · **Level:** Software Engineer 3
**Company:** [Chewy](https://scaleengineer.com/companies/chewy)
**Difficulty:** Medium to Hard
**Salary:** US$120000 - US$160000
**Experience:** 4 - 8
**Timeline:** ~7 days
The Software Engineer 3 interview at Chewy is designed to assess a candidate's technical proficiency, problem-solving abilities, and cultural fit within the company. It typically involves multiple rounds focusing on data structures, algorithms, system design, and behavioral aspects.
Canonical: https://scaleengineer.com/interviews/chewy/software-engineer-3-software-engineer
---
## Overall evaluation

- Technical Skills
- Communication
- Cultural Fit

## Questions asked

- Given an array of integers, find the contiguous subarray with the largest sum.
- Design a URL shortening service like bit.ly.
- Tell me about a time you had to deal with a difficult stakeholder.
- Implement a function to reverse a linked list.
- How would you design a system to handle real-time notifications for a social media platform?
- Describe a situation where you failed and what you learned from it.
- What are the trade-offs between SQL and NoSQL databases?
- How do you approach performance optimization in your code?
- Tell me about a project you are particularly proud of and your role in it.
- Explain the concept of eventual consistency.

## Preparation tips

### lists

- Review fundamental data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, graph traversal).
- Practice coding problems on platforms like LeetCode, HackerRank, or AlgoExpert, focusing on medium to hard difficulty.
- Study system design concepts, including scalability, reliability, databases, caching, and message queues.
- Prepare for behavioral questions using the STAR method (Situation, Task, Action, Result).
- Research Chewy's mission, values, and recent news to understand the company culture and business.
- Prepare thoughtful questions to ask the interviewers about the role, team, and company.

### studyPlan

- {"title":"Data Structures and Algorithms Fundamentals","longDescription":"Weeks 1-2: Focus on core data structures (Arrays, Linked Lists, Stacks, Queues, Hash Tables) and basic algorithms (Sorting, Searching). Practice implementing these from scratch and analyze their time and space complexity. Aim for 2-3 LeetCode medium problems per day.","shortDescription":"Weeks 1-2: Data Structures & Basic Algorithms. LeetCode Mediums."}
- {"title":"Advanced Algorithms and System Design Introduction","longDescription":"Weeks 3-4: Dive into more advanced algorithms like Dynamic Programming, Graph Algorithms (BFS, DFS, Dijkstra), and Tree Traversals. Continue practicing LeetCode problems, increasing the difficulty to include some hard problems. Start exploring system design concepts.","shortDescription":"Weeks 3-4: Advanced Algorithms & Intro to System Design. LeetCode Medium/Hard."}
- {"title":"System Design and Behavioral Preparation","longDescription":"Weeks 5-6: Deepen your understanding of system design principles. Study common patterns for building scalable and reliable systems (e.g., load balancing, caching strategies, database choices, microservices). Practice system design case studies and behavioral questions.","shortDescription":"Weeks 5-6: System Design Deep Dive & Behavioral Prep. STAR method."}
- {"title":"Final Review and Mock Interviews","longDescription":"Week 7: Mock interviews with peers or mentors. Review all topics, focusing on areas where you feel less confident. Refine your answers to behavioral questions and prepare insightful questions for the interviewers.","shortDescription":"Week 7: Mock Interviews & Final Review."}

## Location differences

- {"location":"Seattle","differences":{"tips":["Be prepared to discuss your experience with microservices architecture.","Highlight any contributions to open-source projects.","Emphasize your ability to lead technical discussions and mentor team members."],"interviewFocus":["System design and scalability for distributed applications.","Experience with cloud platforms (AWS, Azure, GCP).","Leadership and mentorship capabilities."],"commonQuestions":["Describe a challenging technical problem you solved at your previous company.","How do you approach debugging a complex issue in a distributed system?","Tell me about a time you had to mentor a junior engineer."]}}
- {"location":"Boston","differences":{"tips":["Be ready to whiteboard solutions to common coding problems.","Showcase your understanding of object-oriented design principles.","Provide specific examples of how you've contributed to team success."],"interviewFocus":["Proficiency in core Java or Python.","Understanding of data structures and algorithms.","Collaboration and communication skills."],"commonQuestions":["How do you ensure code quality and maintainability in a large codebase?","Describe your experience with agile development methodologies.","Tell me about a time you disagreed with a technical decision and how you handled it."]}}

## Round 0: HR/Recruiter Screen
**Type:** HR/Recruiter Screen · **Difficulty:** Easy · **Duration:** 30 min
Initial screening to discuss background, motivation, and logistics.
This is typically the first or last touchpoint with the recruiting team. They will discuss your background, interest in Chewy, salary expectations, and answer any logistical questions you may have about the process or the company. This round helps ensure alignment on basic requirements and provides a final opportunity for you to express your interest.
**Interviewers look for:** Genuine interest in Chewy and the specific role.; Clarity on career aspirations.; Engagement and thoughtful questions.
**Evaluation criteria:** Candidate's interest in the role and company; Alignment of candidate's goals with opportunities at Chewy; Overall impression and enthusiasm
**Common rejection reasons:** Lack of enthusiasm for the role or company.; Unclear career goals.; Asking questions that indicate a lack of research.; Poor fit with the team's dynamics.
## Questions

- Why are you interested in Chewy?
- What are your salary expectations?
- Do you have any questions for me?

## Preparation tips

- Be prepared to discuss your salary expectations.
- Have questions ready about the role, team, or company culture.
- Reiterate your interest and enthusiasm for the position.

## Round 1: Technical Coding Round 1
**Type:** Data Structures and Algorithms Interview · **Difficulty:** Medium · **Duration:** 45 min
Coding challenge focusing on data structures and algorithms.
This round focuses on your fundamental programming skills. You will be asked to solve one or two coding problems, typically involving data structures and algorithms. The interviewer will assess your ability to write clean, efficient, and correct code, as well as your thought process in arriving at the solution. Expect to write code in a shared editor or on a whiteboard.
**Interviewers look for:** Strong grasp of data structures and algorithms.; Clean and efficient coding practices.; Logical thinking and problem-solving approach.; Ability to communicate technical ideas effectively.
**Evaluation criteria:** Correctness of the solution; Efficiency of the solution (time and space complexity); Code quality and readability; Ability to explain the approach clearly; Handling of edge cases
**Common rejection reasons:** Inability to solve coding problems within the given time.; Poor understanding of fundamental data structures and algorithms.; Lack of clarity in explaining the thought process.; Suboptimal solutions or inefficient code.
## Questions

- Given a binary tree, determine if it is a valid binary search tree.
- Find the kth largest element in an unsorted array.

## Preparation tips

- Practice coding problems on platforms like LeetCode.
- Focus on understanding time and space complexity.
- Be prepared to explain your approach before coding.
- Test your code with various edge cases.

## Round 2: System Design Round
**Type:** System Design Interview · **Difficulty:** Hard · **Duration:** 60 min
Design a scalable software system.
This round assesses your ability to design and architect software systems. You'll be given an open-ended problem, such as designing a specific service or application (e.g., a social media feed, a URL shortener, a ride-sharing service). The interviewer will evaluate your ability to break down the problem, identify requirements, propose a high-level design, and then dive deeper into specific components, considering scalability, reliability, and trade-offs.
**Interviewers look for:** Ability to design complex systems from scratch.; Knowledge of distributed systems principles.; Pragmatic approach to problem-solving.; Clear communication of design choices and trade-offs.
**Evaluation criteria:** System design approach; Scalability considerations; Reliability and fault tolerance; Trade-off analysis; Understanding of various system components (databases, caching, messaging)
**Common rejection reasons:** Inability to design scalable and robust systems.; Lack of understanding of distributed systems concepts.; Poor trade-off analysis.; Not considering failure scenarios or bottlenecks.
## Questions

- Design a system like Twitter's news feed.
- Design a rate limiter.

## Preparation tips

- Study common system design patterns and concepts.
- Practice designing various types of systems.
- Be prepared to discuss trade-offs for different design choices.
- Think about scalability, availability, and performance.

## Round 3: Behavioral and Managerial Round
**Type:** Behavioral and Managerial Interview · **Difficulty:** Medium · **Duration:** 45 min
Behavioral questions and discussion about your experience and fit.
This round focuses on your past experiences and how you handle various workplace situations. You'll be asked behavioral questions that probe your skills in areas like teamwork, conflict resolution, leadership, and problem-solving. The interviewer will use the STAR method (Situation, Task, Action, Result) to evaluate your responses. This is also an opportunity to assess your cultural fit with Chewy.
**Interviewers look for:** Evidence of collaboration and teamwork.; Ability to handle challenging situations.; Alignment with Chewy's core values.; Passion for technology and the company's mission.
**Evaluation criteria:** Behavioral competencies (teamwork, problem-solving, leadership); Cultural fit with Chewy; Motivation and career goals; Communication and interpersonal skills
**Common rejection reasons:** Lack of alignment with company values.; Poor communication or interpersonal skills.; Inability to provide specific examples for behavioral questions.; Negative attitude or lack of enthusiasm.
## Questions

- Tell me about a time you had to work with a difficult colleague.
- Describe a project where you took initiative or demonstrated leadership.
- How do you stay updated with new technologies?

## Preparation tips

- Prepare examples using the STAR method for common behavioral questions.
- Reflect on your strengths, weaknesses, and career aspirations.
- Understand Chewy's company culture and values.
- Be honest and authentic in your responses.