Zillow

Senior Engineer

Software EngineerP4Hard

The Senior Engineer (P4) interview process at Zillow 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, culminating in a hiring manager discussion.

Rounds

4

Timeline

~14 days

Experience

5 - 10 yrs

Salary Range

US$140000 - US$180000

Total Duration

180 min

Overall Evaluation Criteria

Technical Skills

Technical proficiency in relevant programming languages and frameworks.
Problem-solving skills and analytical thinking.
Ability to design scalable and robust systems.
Communication and collaboration skills.
Leadership potential and ability to mentor others.
Alignment with Zillow's values and culture.

Problem Solving & Analytical Skills

Clarity of thought and articulation of solutions.
Ability to break down complex problems into manageable parts.
Logical reasoning and systematic approach to problem-solving.
Creativity and innovation in finding solutions.

System Design

Understanding of distributed systems principles.
Ability to design for scalability, reliability, and maintainability.
Consideration of trade-offs and constraints.
Knowledge of relevant technologies and patterns.

Behavioral & Leadership

Examples of leadership and initiative.
Ability to influence and mentor team members.
Collaboration with cross-functional teams.
Adaptability and resilience in challenging situations.

Preparation Tips

1Review fundamental computer science concepts (data structures, algorithms, operating systems, databases).
2Practice coding problems on platforms like LeetCode, HackerRank, or Coderbyte, focusing on medium to hard difficulty.
3Study system design principles and common architectural patterns (e.g., microservices, caching, load balancing, message queues).
4Prepare to discuss your past projects in detail, highlighting your contributions, challenges, and learnings.
5Research Zillow's products, services, and engineering culture.
6Practice behavioral questions using the STAR method (Situation, Task, Action, Result).
7Understand Zillow's business domain and how technology drives its success.

Study Plan

1

Data Structures and Algorithms

Weeks 1-2: Data Structures & Algorithms. Practice coding problems.

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 coding problems related to these topics on platforms like LeetCode, aiming for at least 2-3 problems per day.

2

System Design

Weeks 3-4: System Design. Study architecture and patterns.

Weeks 3-4: Dive into System Design. Study concepts like scalability, availability, reliability, consistency, load balancing, caching, databases (SQL vs. NoSQL), message queues, and microservices architecture. Review common system design interview questions and practice designing systems like Twitter feed, URL shortener, or a distributed cache.

3

Behavioral and Leadership

Week 5: Behavioral Prep. Use STAR method.

Week 5: Behavioral and Leadership Preparation. Reflect on your past experiences and prepare stories using the STAR method for common behavioral questions related to teamwork, conflict resolution, leadership, failure, and success. Understand Zillow's values and how your experiences align with them.

4

Mock Interviews and Refinement

Week 6: Mock Interviews & Refinement.

Week 6: Mock Interviews and Refinement. Conduct mock interviews with peers or mentors, focusing on both technical and behavioral aspects. Get feedback on your problem-solving approach, communication, and system design explanations. Review areas where you need improvement and refine your answers.

Commonly Asked Questions

Tell me about a time you had to deal with a difficult stakeholder. How did you handle it?
Design a system to recommend properties to Zillow users.
Given a large dataset of user clickstream data, how would you identify fraudulent activity?
Describe a situation where you disagreed with your manager's technical approach. What did you do?
How would you design a distributed cache for Zillow's real estate data?
What are the trade-offs between monolithic and microservices architectures?
How do you ensure the quality and testability of your code?
Tell me about a time you failed. What did you learn from it?
Design a system to handle real-time notifications for Zillow users (e.g., price drops, new listings).
How would you optimize the performance of a database query that is causing slow page loads?

Location-Based Differences

Seattle

Interview Focus

Deep understanding of distributed systems and cloud technologies (AWS, Azure, GCP).Experience with large-scale data processing and analytics.Strong problem-solving and debugging skills in a production environment.Ability to lead technical discussions and mentor team members.Understanding of Zillow's business domain and how technology supports it.

Common Questions

How would you design a real-time bidding system for Zillow's advertising platform?

Discuss a complex technical challenge you faced and how you overcame it.

Describe your experience with cloud-native architectures and microservices.

How do you ensure the scalability and reliability of a distributed system?

Tell me about a time you had to mentor junior engineers.

Tips

Research Zillow's tech stack and recent engineering blog posts.
Prepare to discuss your contributions to open-source projects or significant technical initiatives.
Be ready to articulate your thought process clearly and concisely.
Familiarize yourself with common interview patterns for senior roles in tech.
Practice explaining complex technical concepts to both technical and non-technical audiences.

San Francisco

Interview Focus

Proficiency in data structures and algorithms, with an emphasis on practical application.Experience with building and scaling web applications and services.Strong understanding of software development best practices, including testing and CI/CD.Ability to collaborate effectively with product managers and other stakeholders.Demonstrated leadership potential and experience in driving technical projects.

Common Questions

Design a system to handle Zillow's property listing data, considering real-time updates and search performance.

How would you optimize a slow-performing API endpoint for Zillow's mobile app?

Describe a situation where you had to influence technical decisions across multiple teams.

What are your strategies for maintaining code quality and reducing technical debt in a large codebase?

How do you approach performance tuning for database queries?

Tips

Understand Zillow's core products and services.
Prepare examples that showcase your impact and leadership.
Be ready to discuss trade-offs in system design decisions.
Practice coding problems that involve common data structures and algorithms.
Think about how you would contribute to Zillow's engineering culture.

Process Timeline

1
Technical Coding Round 145m
2
System Design Round60m
3
Behavioral and Leadership Round45m
4
Hiring Manager Round30m

Interview Rounds

4-step process with detailed breakdown for each round

1

Technical Coding Round 1

Coding challenge to assess fundamental technical skills.

Data Structures And Algorithms InterviewHard
45 minSoftware Engineer (Mid-level to Senior)

This round focuses on your core technical skills. You will be presented with one or two coding problems that require you to implement solutions using appropriate data structures and algorithms. The interviewer will assess your ability to write clean, efficient, and correct code, as well as your problem-solving approach and communication skills. Expect questions that test your understanding of time and space complexity.

What Interviewers Look For

Strong grasp of data structures and algorithms.Ability to translate a problem into working code.Attention to detail and thoroughness.Problem-solving approach and adaptability.

Evaluation Criteria

Correctness of the solution.
Efficiency of the algorithm (time and space complexity).
Code quality, readability, and maintainability.
Ability to handle edge cases and constraints.
Communication of the thought process.

Questions Asked

Given a binary tree, find the lowest common ancestor of two given nodes.

TreeRecursionBinary Tree

Implement a function to find the k-th largest element in an unsorted array.

ArraySortingHeapQuickSelect

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

StackStringParentheses

Preparation Tips

1Practice coding problems on platforms like LeetCode, focusing on medium and hard difficulty.
2Review common data structures (arrays, linked lists, trees, graphs, hash maps) and algorithms (sorting, searching, dynamic programming).
3Practice explaining your thought process out loud as you code.
4Be prepared to discuss trade-offs of different approaches.
5Write clean, well-commented code.

Common Reasons for Rejection

Inability to articulate thought process clearly.
Lack of depth in understanding fundamental data structures and algorithms.
Poor coding practices or inability to write clean, efficient code.
Failure to consider edge cases or optimize solutions.
2

System Design Round

Design a scalable system for a given problem.

System Design InterviewHard
60 minSenior Software Engineer or Engineering Manager

This round evaluates your ability to design complex, scalable, and reliable systems. You will be given an open-ended problem, such as designing a specific Zillow feature or a core system component. The interviewer will expect you to ask clarifying questions, define requirements, propose a high-level design, dive into specific components, discuss data models, APIs, and potential bottlenecks, and justify your design choices.

What Interviewers Look For

Experience in designing large-scale systems.Understanding of distributed systems principles.Ability to think critically about system components and interactions.Pragmatic approach to problem-solving.Clear communication of complex ideas.

Evaluation Criteria

Scalability of the proposed design.
Reliability and fault tolerance.
Performance considerations (latency, throughput).
Choice of technologies and architectural patterns.
Clarity and structure of the design explanation.
Ability to handle trade-offs and constraints.

Questions Asked

Design a system to handle Zillow's property listing data, including updates and search functionality.

System DesignScalabilityDatabasesSearch

Design a real-time notification system for Zillow users.

System DesignReal-timeWebSocketsMessage Queues

How would you design a system to recommend properties to users based on their browsing history?

System DesignMachine LearningRecommendation SystemsData Processing

Preparation Tips

1Study system design concepts: load balancing, caching, databases (SQL vs. NoSQL), message queues, microservices, CAP theorem.
2Practice designing common systems (e.g., Twitter feed, URL shortener, ride-sharing app).
3Be prepared to discuss trade-offs between different design choices.
4Think about scalability, availability, and maintainability.
5Clearly articulate your design and reasoning.

Common Reasons for Rejection

Inability to design a scalable and robust system.
Lack of understanding of distributed systems concepts.
Poor consideration of trade-offs and failure to address potential bottlenecks.
Inability to communicate design choices effectively.
3

Behavioral and Leadership Round

Assess behavioral competencies and cultural fit.

Behavioral InterviewMedium
45 minHiring Manager or Senior Team Member

This round assesses your behavioral competencies and cultural fit. You will be asked questions about your past experiences, focusing on how you've handled various situations related to teamwork, leadership, conflict resolution, challenges, and successes. The interviewer will use the STAR method (Situation, Task, Action, Result) to evaluate your responses and understand your working style and values.

What Interviewers Look For

Evidence of past behavior that predicts future performance.Ability to work effectively in a team.Leadership potential and initiative.Self-awareness and ability to learn from mistakes.Cultural fit with Zillow.

Evaluation Criteria

Demonstrated leadership and initiative.
Teamwork and collaboration skills.
Problem-solving and decision-making in past situations.
Adaptability and resilience.
Communication and interpersonal skills.
Alignment with Zillow's core values.

Questions Asked

Tell me about a time you had to lead a project from start to finish. What were the challenges and how did you overcome them?

LeadershipProject ManagementProblem Solving

Describe a situation where you had a conflict with a colleague. How did you resolve it?

Conflict ResolutionTeamworkCommunication

Tell me about a time you failed at something. What did you learn from that experience?

FailureLearningResilienceSelf-awareness

How do you prioritize your work when you have multiple competing deadlines?

Time ManagementPrioritizationOrganization

Preparation Tips

1Prepare specific examples from your past experience using the STAR method.
2Reflect on Zillow's company values and prepare examples that demonstrate alignment.
3Be honest and authentic in your responses.
4Practice articulating your experiences clearly and concisely.
5Think about how you contribute to a positive team environment.

Common Reasons for Rejection

Lack of self-awareness or inability to reflect on past experiences.
Inconsistent or vague answers to behavioral questions.
Poor communication or interpersonal skills.
Lack of alignment with Zillow's values or culture.
Inability to demonstrate leadership or teamwork.
4

Hiring Manager Round

Final discussion with the hiring manager.

Hiring Manager DiscussionMedium
30 minHiring Manager

This is typically the final round where you meet with the hiring manager. The focus is on discussing your career goals, understanding your motivations for joining Zillow, and ensuring a good fit with the team and the manager's expectations. It's also an opportunity for you to ask any remaining questions about the role, team, or company.

What Interviewers Look For

Candidate's motivation for the role and Zillow.Alignment of candidate's career goals with opportunities at Zillow.Candidate's understanding of the role and team.Overall fit and potential for long-term success.

Evaluation Criteria

Alignment with the team's goals and projects.
Enthusiasm for the role and Zillow.
Career aspirations and growth potential.
Cultural fit with the manager and team.
Mutual understanding of expectations.

Questions Asked

What are your long-term career goals, and how does this role at Zillow align with them?

Career GoalsMotivationFit

What interests you most about working on this particular team at Zillow?

InterestTeam FitMotivation

What are your expectations for this role and for your manager?

ExpectationsManager RelationshipRole Clarity

Preparation Tips

1Research the hiring manager and their team's work.
2Prepare thoughtful questions about the role, team, and company culture.
3Clearly articulate why you are interested in this specific role at Zillow.
4Be prepared to discuss your career aspirations and how this role fits into them.
5Show enthusiasm and a positive attitude.

Common Reasons for Rejection

Lack of alignment with the team's technical direction.
Unrealistic salary expectations.
Poor fit with the team's dynamics or manager's style.
Lack of enthusiasm or clear career goals.

Commonly Asked DSA Questions

Frequently asked coding questions at Zillow

View all
Valid ParenthesesEASYFind First and Last Position of Element in Sorted ArrayMEDIUMNumber of IslandsMEDIUM