# Software Engineer
**Role:** Software Engineer · **Level:** Fellow Engineer
**Company:** [InMobi](https://scaleengineer.com/companies/inmobi)
**Difficulty:** Hard
**Salary:** US$180000 - US$250000
**Experience:** 8 - 15
**Timeline:** ~14 days
This interview process is designed to assess candidates for the Fellow Engineer role at InMobi, focusing on deep technical expertise, problem-solving abilities, and leadership potential. The process involves multiple rounds to evaluate a candidate's fit across technical skills, behavioral aspects, and alignment with InMobi's culture and values.
Canonical: https://scaleengineer.com/interviews/inmobi/fellow-engineer-software-engineer
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## Overall evaluation

- Technical Proficiency
- System Design & Architecture
- Leadership & Collaboration
- Cultural Fit & Motivation

## Questions asked

- Design a system to handle real-time analytics for a mobile application.
- How would you optimize a database query that is causing performance issues?
- Describe a situation where you had to lead a team through a difficult technical challenge.
- What are the trade-offs between using a monolithic architecture versus a microservices architecture?
- How do you ensure the security of a distributed system?
- Tell me about a time you disagreed with a technical decision made by your manager or team.
- How would you design a recommendation engine for an e-commerce platform?
- What are the challenges of building a global, low-latency service?
- How do you approach mentoring junior engineers and fostering their growth?
- Explain the concept of eventual consistency and when it's appropriate to use.
- Describe a time you failed and what you learned from it.
- How do you handle technical debt and prioritize its resolution?
- Design a distributed rate limiter.
- What are your thoughts on the future of AI in the adtech space?
- How do you ensure code quality and maintainability in a large codebase?

## Preparation tips

### lists

- Revisit fundamental computer science concepts: data structures, algorithms, operating systems, and databases.
- Practice coding problems on platforms like LeetCode, HackerRank, focusing on medium to hard difficulty.
- Deep dive into system design principles: scalability, availability, consistency, fault tolerance, load balancing, caching, databases, messaging queues.
- Study common distributed systems patterns and technologies (e.g., microservices, CAP theorem, consensus algorithms).
- Prepare to discuss your past projects in detail, focusing on your contributions, technical challenges, and learnings.
- Understand InMobi's business, products, and the adtech industry landscape.
- Develop a strong understanding of behavioral interview techniques (STAR method) and prepare examples for leadership, teamwork, and problem-solving scenarios.
- Research common interview questions for senior engineering roles and practice your answers.
- Be ready to articulate your technical vision and how you would approach complex problems.
- Prepare thoughtful questions to ask the interviewers about the role, team, and company.

### studyPlan

- {"title":"Data Structures & Algorithms","longDescription":"Weeks 1-2: Focus on core Data Structures and Algorithms. Cover arrays, linked lists, trees, graphs, hash tables, heaps, sorting, searching, dynamic programming, and greedy algorithms. Practice implementing these and analyzing their time and space complexity. Aim for 2-3 problems per day.","shortDescription":"Weeks 1-2: DSA fundamentals. Practice 2-3 problems/day."}
- {"title":"System Design","longDescription":"Weeks 3-4: Dive into System Design. Study concepts like load balancing, caching, databases (SQL vs NoSQL), message queues, microservices, API design, CAP theorem, and consistency models. Work through common system design case studies (e.g., designing Twitter feed, URL shortener, distributed cache).","shortDescription":"Weeks 3-4: System Design principles and case studies."}
- {"title":"Distributed Systems & Scalability","longDescription":"Week 5: Focus on Distributed Systems and Scalability. Understand concepts like consensus algorithms (Paxos, Raft), distributed transactions, sharding, replication, and fault tolerance. Explore technologies like Kafka, Cassandra, Redis, and Kubernetes.","shortDescription":"Week 5: Distributed Systems, Scalability, and related technologies."}
- {"title":"Behavioral & Leadership","longDescription":"Week 6: Behavioral and Leadership Preparation. Prepare examples using the STAR method for common behavioral questions related to leadership, teamwork, conflict resolution, handling failure, and influencing others. Research InMobi's values and culture.","shortDescription":"Week 6: Behavioral preparation (STAR method) and company research."}
- {"title":"Mock Interviews & Review","longDescription":"Week 7: Mock Interviews and Review. Conduct mock interviews for both technical and behavioral rounds. Identify weak areas and revisit them. Practice articulating your thoughts clearly and concisely. Review your past projects and prepare to discuss them in depth.","shortDescription":"Week 7: Mock interviews, review weak areas, project discussion prep."}

## Location differences

- {"location":"Bangalore","differences":{"tips":["Emphasize experience with large-scale, distributed systems relevant to the Indian market.","Highlight any contributions to open-source projects or technical communities.","Be prepared to discuss your leadership style and how you foster innovation.","Showcase your ability to adapt to rapidly changing technological landscapes.","Research InMobi's recent technological advancements and business strategies."],"interviewFocus":["Deep dive into system design and architecture for high-traffic applications.","Leadership and mentorship capabilities.","Strategic thinking and long-term technical vision.","Understanding of distributed systems and scalability challenges specific to the Indian market.","Ability to drive technical initiatives and influence cross-functional teams."],"commonQuestions":["Discuss a complex technical challenge you faced and how you overcame it.","How do you mentor junior engineers?","Describe a time you had to influence a team or stakeholder to adopt your technical vision.","What are your thoughts on the future of mobile advertising technology?","How do you handle technical debt?","Explain a system you designed that scaled to millions of users."]}}
- {"location":"New York","differences":{"tips":["Highlight experience with international teams and projects.","Be ready to discuss your familiarity with various cloud platforms and their services.","Showcase your understanding of global market dynamics and user behavior.","Prepare examples of how you've driven technical excellence and innovation.","Demonstrate a strong grasp of data-driven decision-making."],"interviewFocus":["Expertise in cloud infrastructure and services.","Experience with global product development and scaling.","Problem-solving skills in a fast-paced, international environment.","Understanding of data privacy regulations and their impact on adtech.","Ability to lead and execute complex technical projects."],"commonQuestions":["How do you approach designing a real-time bidding system?","Describe your experience with cloud-native architectures (AWS, GCP, Azure).","How do you ensure the reliability and fault tolerance of a distributed system?","What are the key considerations for building a global advertising platform?","Discuss a time you had to make a significant technical trade-off.","How do you stay updated with the latest trends in AI/ML for adtech?"]}}

## Round 1: Data Structures & Algorithms
**Type:** Technical Interview (Coding) · **Difficulty:** Hard · **Duration:** 60 min
Assess core CS concepts, data structures, and algorithms through coding problems.
This round focuses on assessing your fundamental computer science knowledge, particularly in data structures and algorithms. You will be presented with coding problems that require you to implement efficient solutions. The interviewer will evaluate your problem-solving approach, your ability to write clean and optimized code, and your understanding of time and space complexity. Expect to be asked to explain your thought process and justify your choices.
**Interviewers look for:** Strong grasp of data structures and algorithms.; Ability to translate a problem into a working code solution.; Logical thinking and systematic approach to problem-solving.; Attention to detail and ability to identify edge cases.
**Evaluation criteria:** Correctness of the solution.; Efficiency of the algorithm (time and space complexity).; Code readability and maintainability.; Ability to handle edge cases.; Communication of thought process.
**Common rejection reasons:** Lack of fundamental CS knowledge.; Inability to write clean, efficient code.; Poor problem-solving approach.; Difficulty in debugging.; Not meeting the expected complexity for the role.
## Questions

- Given a binary tree, find the lowest common ancestor of two given nodes in the tree.
- Implement a function to find the k-th largest element in an unsorted array.
- Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
- Find the shortest path in a grid with obstacles.

## Preparation tips

- Practice coding problems on platforms like LeetCode, HackerRank, focusing on medium to hard difficulty.
- Review common data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming, graph traversal).
- Practice explaining your solution and its complexity clearly.
- Be prepared to write code on a whiteboard or in a shared editor.

## Round 2: System Design & Architecture
**Type:** System Design & Architecture · **Difficulty:** Hard · **Duration:** 60 min
Assess ability to design scalable, reliable, and maintainable systems.
This round evaluates your ability to design robust, scalable, and maintainable systems. You'll be given a high-level problem statement (e.g., design a URL shortener, a social media feed, a real-time bidding system) and expected to propose a comprehensive architecture. The interviewer will probe into your design choices, scalability considerations, data storage strategies, API design, and how you handle potential failures and bottlenecks.
**Interviewers look for:** Deep understanding of system design principles.; Ability to design complex, distributed systems.; Experience with various architectural patterns.; Pragmatic approach to problem-solving and trade-offs.; Knowledge of scalability techniques and database choices.
**Evaluation criteria:** Clarity and completeness of the system design.; Scalability and performance considerations.; Fault tolerance and reliability.; Appropriate choice of technologies and data stores.; Ability to justify design decisions and trade-offs.
**Common rejection reasons:** Inability to design scalable and reliable systems.; Poor understanding of trade-offs.; Lack of experience with distributed systems concepts.; Not considering failure scenarios.; Overly simplistic or overly complex designs.
## Questions

- Design a system like Twitter's news feed.
- Design a distributed rate limiter.
- Design a URL shortening service like bit.ly.
- Design a system to count unique visitors to a website in real-time.

## Preparation tips

- Study common system design patterns and architectural styles (e.g., microservices, event-driven architecture).
- Understand concepts like load balancing, caching, database sharding, replication, CAP theorem, and message queues.
- Practice designing systems for scale and high availability.
- Be prepared to discuss trade-offs between different design choices.
- Familiarize yourself with common technologies used in large-scale systems (e.g., Kafka, Cassandra, Redis, Kubernetes).

## Round 3: Behavioral & Leadership
**Type:** Behavioral & Leadership Interview · **Difficulty:** Medium · **Duration:** 45 min
Assess behavioral competencies, leadership skills, and cultural fit.
This round focuses on your behavioral aspects, leadership potential, and how you collaborate within a team. You'll be asked questions about your past experiences, focusing on situations where you demonstrated leadership, handled conflicts, mentored others, or drove projects to completion. The interviewer will also assess your cultural fit with InMobi and your motivation for joining the company.
**Interviewers look for:** Strong communication and interpersonal skills.; Ability to explain complex technical ideas simply.; Evidence of leadership and mentorship.; Proactive attitude and ownership.; Alignment with InMobi's values.
**Evaluation criteria:** Communication clarity.; Problem-solving approach.; Leadership potential.; Teamwork and collaboration skills.; Cultural alignment.
**Common rejection reasons:** Poor communication skills.; Inability to articulate technical concepts clearly.; Lack of leadership or mentorship experience.; Difficulty in collaborating with others.; Not demonstrating ownership or initiative.
## Questions

- Tell me about a time you had to lead a team through a challenging project. What was your approach?
- Describe a situation where you had a conflict with a colleague or manager. How did you resolve it?
- How do you mentor junior engineers? Give an example.
- What are your strengths and weaknesses as an engineer?
- Why are you interested in InMobi and this role?

## Preparation tips

- Prepare examples using the STAR method (Situation, Task, Action, Result) for common behavioral questions.
- Think about situations where you showed leadership, teamwork, problem-solving, and conflict resolution.
- Be ready to discuss your career goals and why you are interested in InMobi.
- Research InMobi's mission, values, and culture.
- Practice articulating your thoughts clearly and concisely.

## Round 4: Managerial / Leadership Interview
**Type:** Managerial / Leadership Interview · **Difficulty:** Hard · **Duration:** 60 min
Assess strategic thinking, technical vision, and leadership alignment with senior management.
This final round is with senior leadership and focuses on your strategic thinking, technical vision, and overall fit for a senior role at InMobi. You'll discuss your experience in driving technical strategy, influencing product roadmaps, and contributing to the company's growth. Expect questions about your leadership philosophy, how you approach complex business problems with technology, and your long-term career aspirations.
**Interviewers look for:** Visionary thinking and ability to anticipate future trends.; Strong understanding of business objectives and how technology supports them.; Proven track record of driving significant technical initiatives.; Ability to influence and inspire teams.; Alignment with InMobi's long-term goals.
**Evaluation criteria:** Strategic thinking and vision.; Understanding of business impact.; Technical leadership and influence.; Ability to drive innovation.; Long-term career aspirations and alignment.
**Common rejection reasons:** Lack of strategic thinking.; Inability to align technical vision with business goals.; Poor understanding of the adtech industry.; Not demonstrating the required level of seniority or impact.; Concerns about long-term contribution.
## Questions

- What is your vision for the future of mobile advertising technology?
- How would you approach building a new product from scratch at InMobi?
- Describe a time you had to make a significant technical decision that had a major business impact.
- How do you foster innovation within an engineering team?
- Where do you see yourself in 5 years, and how does this role align with that?

## Preparation tips

- Think about your career trajectory and how this role fits into your long-term goals.
- Prepare to discuss your vision for technology in the adtech space.
- Understand InMobi's business strategy and how engineering contributes to it.
- Be ready to discuss high-level architectural challenges and solutions.
- Prepare insightful questions for the senior leadership.