# Senior Software engineer
**Role:** Software Engineer · **Level:** L5
**Company:** [Wish](https://scaleengineer.com/companies/wish)
**Difficulty:** Hard
**Salary:** US$140000 - US$180000
**Experience:** 5 - 10
**Timeline:** ~7 days
The Senior Software Engineer (L5) interview at Wish is a comprehensive process designed to assess a candidate's technical expertise, problem-solving abilities, system design skills, and cultural fit. The process typically involves multiple rounds, including technical interviews, a system design interview, and a behavioral/managerial interview. The goal is to identify candidates who can not only write high-quality code but also design scalable and robust systems, mentor junior engineers, and contribute positively to Wish's engineering culture.
Canonical: https://scaleengineer.com/interviews/wish/l5-software-engineer
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## Overall evaluation

- Technical Skills
- System Design & Architecture
- Leadership & Ownership
- Cultural Fit & Behavioral

## Questions asked

- Design a system to track user activity on a website.
- How would you implement a rate limiter?
- Explain the difference between TCP and UDP.
- Describe a situation where you had to deal with a difficult stakeholder.
- What are your strengths and weaknesses as a software engineer?
- How do you approach debugging a complex issue in a production environment?
- Design a distributed cache.
- Tell me about a time you failed and what you learned from it.
- What is eventual consistency?
- How would you design a notification system?

## Preparation tips

### lists

- Review fundamental computer science concepts: data structures, algorithms, operating systems, databases.
- Practice coding problems on platforms like LeetCode, HackerRank, focusing on medium to hard difficulty.
- Study system design principles and common patterns (e.g., load balancing, caching, message queues, microservices).
- Prepare to discuss your past projects in detail, focusing on your contributions, challenges, and learnings.
- Understand Wish's products and business to better contextualize your answers.
- Research common behavioral interview questions and prepare STAR method (Situation, Task, Action, Result) responses.
- Practice mock interviews to simulate the actual interview environment.

### studyPlan

- {"title":"Data Structures & Algorithms","longDescription":"Weeks 1-2: Focus on Data Structures and Algorithms. Cover arrays, linked lists, trees, graphs, hash tables, heaps, sorting, searching, dynamic programming, and graph traversal algorithms. Practice implementing these and analyzing their time and space complexity.","shortDescription":"Weeks 1-2: DSA fundamentals and practice."}
- {"title":"System Design","longDescription":"Weeks 3-4: Dive into System Design. Study concepts like scalability, availability, reliability, consistency, CAP theorem, load balancing, caching strategies, database design (SQL vs. NoSQL), message queues, and microservices architecture. Review common system design interview questions and practice designing systems.","shortDescription":"Weeks 3-4: System Design principles and practice."}
- {"title":"Behavioral & Cultural Fit","longDescription":"Week 5: Prepare for Behavioral and Managerial rounds. Reflect on your career experiences, identify key projects, challenges, and successes. Prepare STAR method answers for questions related to teamwork, leadership, conflict resolution, and handling failure. Understand Wish's culture and values.","shortDescription":"Week 5: Behavioral and cultural fit preparation."}
- {"title":"Mock Interviews & Review","longDescription":"Week 6: Mock Interviews and Review. Conduct mock interviews for both technical and system design rounds. Get feedback and identify areas for improvement. Review all topics covered and refine your answers.","shortDescription":"Week 6: Mock interviews and final review."}

## Location differences

- {"location":"San Francisco","differences":{"tips":["Research the specific technologies used by the team in this location.","Be prepared to discuss your contributions to open-source projects if applicable.","Highlight experience with performance optimization and scalability challenges."],"interviewFocus":["Emphasis on practical application of distributed systems concepts.","Deeper dive into specific technologies relevant to the team's stack.","More focus on understanding the candidate's experience with large-scale systems."],"commonQuestions":["How would you design a URL shortening service like bit.ly?","Discuss a challenging technical problem you solved recently.","Explain the trade-offs between different database technologies for a specific use case.","How do you handle concurrency in a distributed system?","Describe your experience with cloud platforms (AWS, GCP, Azure)."]}}
- {"location":"Remote","differences":{"tips":["Brush up on data structures and algorithms, especially those related to graph traversal and dynamic programming.","Practice explaining your thought process clearly and concisely.","Be ready to discuss trade-offs and justify your design decisions."],"interviewFocus":["Focus on foundational computer science principles and algorithms.","Assessment of problem-solving skills in a more abstract manner.","Evaluation of the candidate's ability to articulate technical concepts clearly."],"commonQuestions":["Design a system to handle real-time notifications for a social media platform.","How would you optimize a slow database query?","Discuss your approach to testing complex software systems.","What are the principles of good API design?","How do you ensure data consistency in a distributed environment?"]}}

## Round 1: Technical Coding Round 1
**Type:** Data Structures and Algorithms Interview · **Difficulty:** Hard · **Duration:** 45 min
Coding challenge focused on data structures and algorithms.
This round focuses on your core programming skills and problem-solving abilities. You will be asked to solve one or two coding problems, typically involving data structures and algorithms. The interviewer will assess your ability to understand the problem, devise an efficient solution, implement it correctly, and explain your reasoning. Expect questions that test your knowledge of arrays, strings, linked lists, trees, graphs, hash maps, heaps, sorting, searching, and dynamic programming.
**Interviewers look for:** Strong grasp of data structures and algorithms.; Ability to write clean, efficient, and bug-free code.; Systematic approach to problem-solving.; Clear communication of logic and trade-offs.
**Evaluation criteria:** Correctness of the solution.; Efficiency of the solution (time and space complexity).; Code quality, readability, and maintainability.; Problem-solving approach and ability to break down complex problems.; Communication of thought process.
**Common rejection reasons:** Inability to articulate thought process clearly.; Poor understanding of fundamental data structures and algorithms.; Suboptimal or incorrect code implementation.; Failure to consider edge cases and constraints.
## Questions

- Given a binary tree, find its maximum depth.
- Implement a function to reverse a linked list.
- Find the kth largest element in an unsorted array.

## Preparation tips

- Practice coding problems on platforms like LeetCode, focusing on medium to hard difficulty.
- Understand the time and space complexity of your solutions.
- Practice explaining your thought process out loud.
- Be prepared to discuss alternative approaches and their trade-offs.

## Round 2: System Design Round
**Type:** System Design Interview · **Difficulty:** Hard · **Duration:** 60 min
Design a scalable system based on a given problem statement.
This round assesses your ability to design and architect complex, scalable, and reliable systems. You will be given an open-ended problem (e.g., design Twitter's feed, design a URL shortener) and expected to discuss various aspects of the system, including APIs, data models, scalability bottlenecks, caching strategies, load balancing, and fault tolerance. The focus is on your thought process, trade-off analysis, and ability to make informed design decisions.
**Interviewers look for:** Deep understanding of distributed systems principles.; Ability to design complex systems from scratch.; Proficiency in choosing and justifying technology stacks.; Consideration of non-functional requirements (scalability, availability, latency).; Effective communication of design decisions.
**Evaluation criteria:** Clarity and completeness of the system design.; Scalability and performance considerations.; Reliability and fault tolerance.; Choice of appropriate technologies and trade-offs.; Ability to handle ambiguity and iterate on the design.
**Common rejection reasons:** Inability to design a scalable and reliable system.; Lack of understanding of distributed systems concepts.; Poor trade-off analysis and justification.; Not considering failure scenarios or edge cases.
## Questions

- Design a system like Instagram.
- Design a distributed key-value store.
- How would you design a real-time analytics dashboard?

## Preparation tips

- Study common system design patterns and architectures.
- Practice designing various types of systems (e.g., social media, e-commerce, real-time systems).
- Understand trade-offs between different technologies and approaches.
- Be prepared to draw diagrams and explain your design clearly.
- Consider aspects like data storage, caching, message queues, and API design.

## Round 3: Behavioral and Managerial Round
**Type:** Behavioral / Managerial Interview · **Difficulty:** Medium · **Duration:** 45 min
Assesses behavioral competencies, teamwork, and cultural fit.
This round focuses on your behavioral competencies and cultural fit. The interviewer will ask questions about your past experiences, focusing on how you've handled various situations, worked in teams, demonstrated leadership, and overcome challenges. Prepare to provide specific examples using the STAR method (Situation, Task, Action, Result). The goal is to understand your working style, motivations, and how you align with Wish's values.
**Interviewers look for:** Evidence of collaboration and teamwork.; Examples of leadership and initiative.; Ability to handle challenging situations and learn from mistakes.; Clear communication and active listening skills.; Genuine interest in Wish and the role.
**Evaluation criteria:** Alignment with Wish's culture and values.; Demonstration of leadership and teamwork skills.; Problem-solving and decision-making abilities in past situations.; Communication and interpersonal skills.; Motivation and career aspirations.
**Common rejection reasons:** Lack of alignment with company values.; Poor communication or interpersonal skills.; Inability to provide specific examples of past experiences.; Lack of enthusiasm or motivation for the role.
## Questions

- Tell me about a time you had a conflict with a teammate and how you resolved it.
- Describe a challenging project you worked on and your role in its success.
- How do you stay updated with new technologies?

## Preparation tips

- Review your resume and identify key projects and experiences.
- Prepare STAR method answers for common behavioral questions (e.g., teamwork, conflict, failure, success, leadership).
- Research Wish's company culture, values, and mission.
- Think about why you want to work at Wish and what you can contribute.
- Prepare thoughtful questions to ask the interviewer.