# L3
**Role:** Software Engineer · **Level:** SWE III
**Company:** [Samsara](https://scaleengineer.com/companies/samsara)
**Difficulty:** Medium to Hard
**Salary:** US$140000 - US$180000
**Experience:** 5 - 8
**Timeline:** ~14 days
This interview process is designed to assess candidates for the Software Engineer III (L3) role at Samsara. It evaluates technical proficiency, problem-solving skills, system design capabilities, and cultural fit.
Canonical: https://scaleengineer.com/interviews/samsara/swe-iii-software-engineer
---
## Overall evaluation

- Technical Proficiency
- Problem Solving & Analytical Skills
- System Design & Architecture
- Behavioral & Cultural Fit

## Questions asked

- Design a URL shortening service.
- How would you design a system to track real-time vehicle locations?
- Explain the difference between TCP and UDP.
- Describe a time you had to deal with a difficult stakeholder.
- What are the trade-offs of using a microservices architecture?
- How do you ensure the scalability of your code?
- Write a function to find the kth largest element in an unsorted array.
- Tell me about a project you are most proud of.
- How would you handle a situation where a critical service is down?
- What is eventual consistency and when would you use it?

## Preparation tips

### lists

- Review fundamental data structures and algorithms.
- Practice coding problems on platforms like LeetCode, HackerRank, or Coderbyte.
- Study system design principles and common architectural patterns.
- Prepare to discuss your past projects and technical challenges in detail.
- Research Samsara's products, mission, and values.
- Practice behavioral questions using the STAR method (Situation, Task, Action, Result).
- Understand concepts related to distributed systems, cloud computing, and databases.
- Prepare questions to ask the interviewer about the role, team, and company culture.

### studyPlan

- {"title":"Data Structures and Algorithms","longDescription":"Weeks 1-2: Focus on core data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, graph traversal). Practice implementing these in your preferred language. Aim for 2-3 coding problems per day.","shortDescription":"Weeks 1-2: Data Structures & Algorithms fundamentals. Practice coding problems daily."}
- {"title":"System Design","longDescription":"Weeks 3-4: Dive into system design. Study concepts like scalability, availability, reliability, load balancing, caching, databases (SQL vs. NoSQL), message queues, and microservices. Review common system design interview questions and practice designing systems.","shortDescription":"Weeks 3-4: System Design principles and practice. Focus on scalability and distributed systems."}
- {"title":"Behavioral Preparation","longDescription":"Week 5: Prepare for behavioral questions. Reflect on your past experiences and identify examples that demonstrate leadership, teamwork, problem-solving, and handling challenges. Practice articulating these using the STAR method. Also, research Samsara's company culture and values.","shortDescription":"Week 5: Behavioral preparation using STAR method. Research Samsara's culture."}
- {"title":"Mock Interviews & Final Review","longDescription":"Week 6: Mock interviews. Conduct mock interviews with peers or mentors to simulate the interview environment. Focus on receiving and incorporating feedback on both technical and behavioral aspects. Review any weak areas identified during practice.","shortDescription":"Week 6: Mock interviews and final review of weak areas."}

## Location differences

- {"location":"San Francisco Bay Area","differences":{"tips":["Familiarize yourself with Samsara's technology stack and product offerings.","Prepare to discuss your experience with large-scale data processing and real-time systems.","Be ready to articulate your thought process clearly and concisely.","Showcase your ability to collaborate and communicate effectively."],"interviewFocus":["Emphasis on distributed systems and scalability relevant to Samsara's core products.","Deep dives into cloud technologies (AWS/GCP) and their application.","Problem-solving scenarios often mirror real-world challenges faced by Samsara's engineering teams."],"commonQuestions":["Discuss a challenging technical problem you solved in a distributed system.","How would you design a real-time analytics dashboard for fleet management?","Explain the trade-offs between different caching strategies.","Describe a time you had to mentor junior engineers. What was your approach?","How do you handle production incidents and post-mortems?"]}}
- {"location":"Austin, TX","differences":{"tips":["Highlight your experience with building and maintaining robust software systems.","Be prepared to discuss your contributions to team projects and your problem-solving approach.","Demonstrate a strong understanding of software development lifecycle.","Showcase your ability to adapt to new technologies and challenges."],"interviewFocus":["Focus on practical application of software engineering principles.","Assessment of coding best practices and maintainability.","Understanding of cloud infrastructure and deployment strategies."],"commonQuestions":["How would you optimize a database query for a high-throughput application?","Describe your experience with CI/CD pipelines and infrastructure as code.","Walk me through a system you designed from scratch.","How do you approach code reviews to ensure quality and maintainability?","Tell me about a time you disagreed with a technical decision and how you handled it."]}}

## Round 1: Technical Coding Round 1
**Type:** Data Structures and Algorithms Interview · **Difficulty:** Medium · **Duration:** 45 min
Coding challenge to assess fundamental programming skills.
This round focuses on your fundamental programming skills. You will be asked to solve one or two coding problems that test your knowledge of data structures and algorithms. The interviewer will assess your ability to write correct, efficient, and well-structured code, as well as your approach to problem-solving and your ability to communicate your thought process.
**Interviewers look for:** Strong grasp of data structures and algorithms; Ability to write clean, efficient code; Problem-solving skills; Communication of technical ideas
**Evaluation criteria:** Correctness of the solution; Efficiency of the solution (time and space complexity); Clarity and readability of the code; Ability to explain the approach and trade-offs
**Common rejection reasons:** Inability to articulate thought process; Poor understanding of fundamental algorithms; Inefficient or incorrect code; Lack of problem-solving approach
## Questions

- Given an array of integers, return indices of the two numbers such that they add up to a specific target.
- Implement a function to reverse a linked list.
- Find the kth smallest element in a binary search tree.

## Preparation tips

- Practice coding problems focusing on common data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming).
- Be comfortable coding in your preferred language.
- Think out loud and explain your approach before you start coding.
- Consider edge cases and test your solution thoroughly.

## Round 2: System Design Round
**Type:** System Design Interview · **Difficulty:** Hard · **Duration:** 60 min
Design a scalable system, discussing architecture and trade-offs.
This round evaluates your ability to design and architect software systems. You will be presented with a high-level problem and asked to design a system that meets specific requirements, considering factors like scalability, performance, and reliability. Expect to discuss various components, data models, APIs, and trade-offs.
**Interviewers look for:** Ability to design complex, scalable systems; Deep understanding of distributed systems principles; Pragmatic approach to problem-solving; Clear communication of design choices
**Evaluation criteria:** Scalability of the proposed design; Reliability and availability considerations; Understanding of trade-offs; Clarity and completeness of the design; Knowledge of relevant technologies (databases, caching, messaging)
**Common rejection reasons:** Inability to design scalable systems; Lack of understanding of distributed systems concepts; Poor consideration of trade-offs; Overly simplistic or overly complex solutions
## Questions

- Design a distributed cache system.
- Design a rate limiter.
- Design a system to count unique visitors to a website.

## Preparation tips

- Study common system design patterns and architectural styles (e.g., microservices, event-driven).
- Understand concepts like load balancing, caching, database sharding, replication, and message queues.
- Practice designing systems like social media feeds, URL shorteners, or real-time analytics platforms.
- Be prepared to justify your design choices and discuss alternatives.

## Round 3: Behavioral and Cultural Fit Round
**Type:** Behavioral Interview · **Difficulty:** Medium · **Duration:** 45 min
Assess past experiences, behavioral competencies, and cultural fit.
This round focuses on your past experiences, behavioral competencies, and cultural fit. You'll be asked questions about how you've handled specific situations in previous roles, your strengths and weaknesses, and your motivations. The goal is to understand how you work, collaborate, and align with Samsara's values.
**Interviewers look for:** Evidence of collaboration and teamwork; Ability to handle conflict and challenges constructively; Proactive approach to learning and growth; Alignment with company culture and values
**Evaluation criteria:** Alignment with Samsara's values; Demonstrated teamwork and collaboration; Problem-solving approach in past situations; Leadership potential; Self-awareness and reflection
**Common rejection reasons:** Lack of self-awareness; Poor communication of past experiences; Inability to provide specific examples; Poor cultural fit or misalignment with company values
## Questions

- Tell me about a time you failed. What did you learn from it?
- Describe a challenging project you worked on and how you overcame obstacles.
- How do you handle constructive criticism?
- Why are you interested in Samsara?

## Preparation tips

- Prepare specific examples using the STAR method (Situation, Task, Action, Result) for common behavioral questions.
- Reflect on your career goals and why you are interested in Samsara.
- Be honest and authentic in your responses.
- Show enthusiasm for the role and the company.

## Round 4: Hiring Manager Round
**Type:** Managerial Interview · **Difficulty:** Medium · **Duration:** 45 min
Discuss career aspirations and team fit with the hiring manager.
This final round is typically with the hiring manager. It's an opportunity for the manager to assess your overall fit for the team, discuss your career aspirations, and answer any remaining questions you might have. They will also gauge your understanding of the role and how you can contribute to the team's success.
**Interviewers look for:** Ability to engage in technical discussions; Collaborative spirit; Enthusiasm for the team's work; Potential to grow within the team
**Evaluation criteria:** Technical depth and breadth; Problem-solving approach; Communication and collaboration skills; Potential to contribute to the team; Alignment with team's technical vision
**Common rejection reasons:** Lack of alignment with team's technical direction; Poor communication or collaboration with potential peers; Unrealistic expectations about the role or team dynamics
## Questions

- What are your career aspirations for the next 3-5 years?
- What kind of technical challenges excite you the most?
- How do you stay up-to-date with new technologies?

## Preparation tips

- Be prepared to discuss your career goals and how this role aligns with them.
- Have thoughtful questions ready about the team's projects, challenges, and culture.
- Reiterate your interest in the role and the company.
- Showcase your understanding of the impact you can make.