Netflix Software Engineer Interview Questions + Guide in 2024

Netflix provides digital streaming services that offer TV shows, anime, movies, documentaries, and more based on a subscription model. Netflix is expanding rapidly and needs talented Software Engineers to help innovate its entertainment platform.

This guide is designed for you as the interview process at Netflix for Software Engineers is highly competitive. Let’s embark on this journey together to equip you with valuable insights and tips to appear confident in the interview.

The process for a Netflix Software Engineer interview typically comprises several key stages designed to evaluate you thoroughly.

1. Recruiter Call

The initial step of the Netflix interview process commences with a recruiter call, serving as an introductory discussion. This discussion provides you an opportunity to delve into your background and experiences and express your interest in the role. This interaction sets the stage for further evaluation and progression within the interview process.

2. Hiring Manager Screen

This stage involves a conversation with the Hiring Manager at Netflix to delve deeper into your qualifications, experiences, and overall fit for the role. It’s a crucial step to determine the alignment between your skills and the requirements of the position.

3. Online Technical Video Screening

After successfully clearing the Hiring Manager screen, you proceed to the online technical video screening. Here, you can expect to encounter technical questions related to software engineering concepts, problem-solving, and coding. This stage serves as a means to assess your technical acumen and suitability for the role.

4. On-site Interview

The final stage of the Netflix Software Engineer interview process is the on-site interview. This comprehensive evaluation involves multiple rounds of interviews with different individuals. These interviews may carry a wide array of topics, including technical skills, problem-solving abilities, system design, and cultural fit. The on-site interview provides you with the opportunity to showcase your capabilities and engage in in-depth discussions with members of the Netflix team, ultimately enabling the organization to make well-informed hiring decisions.

During a Netflix Software Engineer interview, you can expect questions covering technical proficiency, problem-solving skills, and cultural fit. These questions explore software engineering principles, algorithms, data structures, and coding in Python or other relevant languages. You might discuss experience with distributed systems, cloud computing, scalability, and performance optimization. Expect questions about past projects, experiences, and alignment with Netflix’s values and mission.

Here are interview questions commonly asked during Netflix Software Engineer interviews:

1. Tell me about a time when you had to work under a tight deadline. How did you manage your time and deliver the project successfully?

By asking this question, your interviewer wants to gauge your ability to handle pressure and perform effectively in high-stakes situations. They want to see evidence of your resilience, composure, and ability to stay focused and productive when faced with tight deadlines and challenging circumstances at work.

How to Answer

Start by describing the situation when you worked under a tight deadline, then explain the actions you took to prioritize tasks and meet the deadline. Finally, discuss the outcome and any lessons learned and keep everything realistic.

Example

“In my previous role, we had a project with a tight deadline. I organized a detailed schedule, delegated tasks effectively, and communicated regularly with team members to ensure progress. As a result, we completed the project on time and received positive feedback from stakeholders.”

2. What is your approach to resolving conflict with co-workers or external stakeholders, partially when you don’t really like them?

When Netflix recruiters ask you about your approach to resolving conflicts with co-workers or external stakeholders, it helps them understand how you handle challenging situations with diplomacy, respect, and maturity, even when personal feelings may be involved.

How to Answer

You can start by highlighting the importance of open communication and understanding in resolving conflicts. Discuss your approach to actively listening to other perspectives and finding common ground for conflict resolution. You can provide examples of specific conflict resolution strategies being practiced in the past. Complete your answer by highlighting successful outcomes and the lessons learned from challenging situations.

Example

“In situations where conflicts arise with co-workers or external stakeholders, particularly when personal feelings may be involved, I prioritize professionalism and effective communication. One approach I take is to actively listen to the concerns and perspectives of all parties involved, regardless of personal preferences. For instance, in a previous project, I encountered disagreements with a team member whose approach differed significantly from mine. Despite our differences, I initiated a private conversation to understand their perspective and find common ground. This experience taught me the importance of maintaining professionalism and fostering constructive dialogue, even in challenging situations.”

3. How do you handle conflicts or disagreements within a team?

By asking about your approach to conflict resolution, recruiters from Netflix assess your ability to communicate diplomatically, listen actively, and find mutually beneficial solutions.

How to Answer

Describe your approach to resolving conflicts, such as active listening, open communication, and seeking common ground. Highlight your ability to collaborate effectively with team members.

Example

“When conflicts arise, I believe in addressing them openly and constructively. I encourage team members to share their perspectives, actively listen to all viewpoints, and work together to find a mutually beneficial solution that promotes team harmony and project success.”

4. Tell me about a time when you exceeded expectations during a project. What did you do, and how did you accomplish it?

By exploring past experiences where you went above and beyond, recruiters from Netflix assess your problem-solving skills, work ethic, and capacity to drive positive outcomes.

How to Answer

Begin by providing context about the project, including the goals, challenges, and your role within the team. Describe the actions you took to surpass expectations, such as taking on additional responsibilities, implementing innovative solutions, or collaborating effectively with team members. Emphasize the impact of your contributions on the project’s success and the outcomes achieved as a result of your efforts. Reflect on the lessons learned from the experience and how it has shaped your approach to future projects.

Example

“In a recent project to overhaul our company’s customer service system, I was tasked with leading a team to streamline our processes and improve customer satisfaction. During the project, we encountered unexpected technical challenges that threatened to delay our timeline and compromise the project’s success. In response, I mobilized the team to brainstorm innovative solutions and implement contingency plans to mitigate risks. Through effective collaboration and strategic decision-making, we not only resolved the challenges but also exceeded our initial goals by achieving a 20% reduction in response time and a 15% increase in customer satisfaction ratings. This experience reinforced the value of proactive problem-solving and effective teamwork in delivering exceptional results, and it has inspired me to approach future projects with the same level of dedication and resilience.”

5. Tell me about a time when you took the initiative to improve a process or implement a new idea.

Your replies show how good you are at spotting ways to make things better, thinking up new solutions, and getting those ideas to work at your job.

How to Answer

Discuss the specific process or idea you identified to improve the process, the steps you took to implement it, and the positive impact it had on the project or team.

Example

“I noticed inefficiencies in our project management process and proposed a new workflow that streamlined communication and task allocation. By implementing this idea, we saw a significant improvement in project efficiency and team collaboration.”

6. You have an array of integers, nums of length n spanning 0 to n with one missing. Write a function missing_number that returns the missing number in the array.

Note: Complexity of O(n) required.

Example:

Input:

nums = [0,1,2,4,5]

missing_number(nums) -> 3

How to Answer

Here’s a Python function missing_number that finds the missing number in the array nums with a complexity of O(n):

def missing_number(nums):

n = len(nums)

expected_sum = n * (n + 1) // 2  # Sum of first n natural numbers

actual_sum = sum(nums)

return expected_sum - actual_sum

# Test the function

nums = [0, 1, 2, 4, 5]

print(missing_number(nums))  # Output should be 3

We calculate the expected sum of the first n natural numbers using the formula n * (n + 1) // 2. Then, we calculate the actual sum of the numbers in the array nums. The difference between the expected sum and the actual sum gives us the missing number.

7. What is the purpose of using RESTful APIs in web development?

Your recruiters evaluate your knowledge of REST architecture and its application in building scalable and interoperable web services.

How to Answer

Explain the principles of Representational State Transfer (REST) and how RESTful APIs facilitate communication between client and server using standard HTTP methods.

Example

“RESTful APIs allow for stateless communication between client and server, enabling scalability and interoperability. They use standard HTTP methods like GET, POST, PUT, and DELETE to perform CRUD operations on resources, making it easier to develop and integrate web services.”

8. Given two sorted lists, write a function to merge them into one sorted list.

Bonus: What’s the time complexity?

Example:

Input:

list1 = [1,2,5]

list2 = [2,4,6]

Output:

def merge_list(list1,list2) -> [1,2,2,4,5,6]**

How to Answer

Here’s a Python function merge_lists to merge two sorted lists into one sorted list:

def merge_lists(list1, list2):

merged_list = []

i = j = 0

while i < len(list1) and j < len(list2):

if list1[i] < list2[j]:

merged_list.append(list1[i])

i += 1

else:

merged_list.append(list2[j])

j += 1

# Add remaining elements from list1, if any

while i < len(list1):

merged_list.append(list1[i])

i += 1

# Add remaining elements from list2, if any

while j < len(list2):

merged_list.append(list2[j])

j += 1

return merged_list

# Test the function

list1 = [1, 2, 5]

list2 = [2, 4, 6]

print(merge_lists(list1, list2))  # Output: [1, 2, 2, 4, 5, 6]

The time complexity of this function is O(n), where n is the total number of elements in both lists. The function iterates through both lists once and compares elements to merge them into the final sorted list. The time complexity is linear with respect to the total number of elements.

9. Describe the differences between synchronous and asynchronous programming.

Recruiter over at Netflix tests your comprehension of fundamental programming concepts and ability to differentiate between synchronous and asynchronous execution models.

How to answer

Differentiate between synchronous programming, where operations occur sequentially, and asynchronous programming, where tasks can run concurrently, allowing non-blocking behavior.

Example

“Synchronous programming executes tasks sequentially, blocking until each operation completes, while asynchronous programming enables tasks to run concurrently, allowing for non-blocking operations and improved performance in I/O-bound applications.”

10. Write a function compute_deviation that takes in a list of dictionaries with a key and list of integers and returns a dictionary with the standard deviation of each list.

Note: This should be done without using the NumPy built-in functions.

Example:

Input:

input = [

{

'key': 'list1',

'values': [4,5,2,3,4,5,2,3],

},

{

'key': 'list2',

'values': [1,1,34,12,40,3,9,7],

}

]

Output:

output = {'list1': 1.12, 'list2': 14.19}

How to Answer

Here’s the implementation of the compute_deviation function:

import math

def compute_deviation(input):

result = {}

for item in input:

key = item['key']

values = item['values']

# Calculate mean

mean = sum(values) / len(values)

# Calculate sum of squared differences

sum_squared_diff = sum((x - mean) ** 2 for x in values)

# Calculate variance

variance = sum_squared_diff / len(values)

# Calculate standard deviation

std_deviation = math.sqrt(variance)

# Add standard deviation to result dictionary

result[key] = round(std_deviation, 2)

return result

# Test the function

input_data = [

{'key': 'list1', 'values': [4, 5, 2, 3, 4, 5, 2, 3]},

{'key': 'list2', 'values': [1, 1, 34, 12, 40, 3, 9, 7]}

]

output = compute_deviation(input_data)

print(output)  # Output: {'list1': 1.12, 'list2': 14.19}

This function iterates through the input list of dictionaries, calculates the mean, variance, and standard deviation for each list of values, and stores the result in the output dictionary with the corresponding key. The standard deviation is rounded to two decimal places before being added to the output dictionary.

11. What is the difference between SQL and NoSQL databases?

This question determines your familiarity with different database paradigms and ability to articulate the distinctions between SQL and NoSQL databases.

How to answer

Explain the distinctions between SQL databases, which use structured query language and have a predefined schema, and NoSQL databases, which are schema-less and offer flexibility in data storage.

Example

“SQL databases like MySQL or PostgreSQL adhere to a structured schema and use SQL for querying, whereas NoSQL databases like MongoDB or Cassandra offer flexibility in schema design and support unstructured data formats like JSON.”

12. Given a JSON string with nested objects, write a function flatten_json that flattens all the objects to a single key-value dictionary. Do not use the library that actually performs this function.

Example:

Input:

import json

json_str = json.dumps({'a':{'b':'c', 'd':'e'}})

Output:

def flatten_json(json_str) -> json.dumps({'a_b':'c', 'a_d':'e'})

Note: Input and output are in string format: use json.dumps() to convert python dictionary to string.

How to answer

Here’s the implementation of the flatten_json function:

import json

def flatten_json(json_str):

# Convert JSON string to dictionary

json_dict = json.loads(json_str)

# Define function to flatten nested dictionaries

def flatten_dict(d, parent_key='', sep='_'):

items = []

for k, v in d.items():

new_key = parent_key + sep + k if parent_key else k

if isinstance(v, dict):

items.extend(flatten_dict(v, new_key, sep=sep).items())

else:

items.append((new_key, v))

return dict(items)

# Flatten the nested dictionary

flattened_dict = flatten_dict(json_dict)

# Convert flattened dictionary to JSON string

flattened_json_str = json.dumps(flattened_dict)

return flattened_json_str

# Test the function

json_str = json.dumps({'a': {'b': 'c', 'd': 'e'}})

output = flatten_json(json_str)

print(output)  # Output: {"a_b": "c", "a_d": "e"}

This function takes a JSON string as input, converts it to a dictionary, recursively flattens the nested dictionaries using the flatten_dict function, and then converts the flattened dictionary back to a JSON string using json.dumps(). The flatten_dict function iterates through the dictionary and flattens nested dictionaries by concatenating keys with underscores.

13. How do you optimize website performance for faster loading times?

The recruiter asks this question to gauge your ability to enhance website performance for faster loading times. By answering, you can demonstrate your understanding of factors such as server response time, image optimization, and caching.

How to answer

Discuss techniques such as minimizing HTTP requests, leveraging browser caching, optimizing images, using Content Delivery Networks (CDNs), and reducing server response times.

Example

“To optimize website performance, we can minimize HTTP requests by combining CSS and JavaScript files, leverage browser caching for static resources, compress images to reduce file size, utilize CDNs to distribute content closer to users, and optimize server configurations for faster response times.”

14. Given two strings A and B, write a function can_shift to return whether or not A can be shifted some number of places to get B.

Example:

Input:

A = 'abcde'

B = 'cdeab'

can_shift(A, B) == True

A = 'abc'

B = 'acb'

can_shift(A, B) == False

How to answer

Here’s the implementation of the can_shift function:

def can_shift(A, B):

# Check if the lengths of strings A and B are equal

if len(A) != len(B):

return False

# Double the string A to handle cases where B is a rotation of A

doubled_A = A + A

# Check if B is a substring of doubled A

if B in doubled_A:

return True

else:

return False

# Test cases

A1, B1 = 'abcde', 'cdeab'

print(can_shift(A1, B1))  # Output: True

A2, B2 = 'abc', 'acb'

print(can_shift(A2, B2))  # Output: False

• The function first checks if the lengths of strings A and B are equal. If they are not, it returns False because no amount of shifting will make A equal to B.
• Then, it doubles the string A to handle cases where B is a rotation of A (e.g., ‘abcde’ and ‘cdeab’).
• Finally, it checks if B is a substring of the doubled A. If it is, then A can be shifted to obtain B, and the function returns True; otherwise, it returns False.

15. What are the advantages of using containerization with Docker?

By asking this question, the recruiter from Netflix assesses your understanding of containerization benefits and your proficiency in leveraging Docker for application deployment and management.

How to answer

Highlight benefits such as lightweight resource isolation, portability, scalability, and reproducibility of environments using Docker containers.

Example

“Docker provides lightweight, isolated containers that encapsulate application dependencies, making it easier to deploy and scale applications across different environments. It offers portability and scalability and ensures consistency between development, testing, and production environments.”

16. Given a list of integers and an integer N, write a function sum_to_n to find all combinations that sum to the value N.

Example:

Input:

integers = [2,3,5]

N = 8

Output:

def sum_to_n(integers, N) ->

[

[2,2,2,2],

[2,3,3],

[3,5]

]

How to answer

Here’s the implementation of the sum_to_n function:

def sum_to_n(integers, N):

def backtrack(start, target, path):

if target == 0:

result.append(path)

return

if target < 0:

return

for i in range(start, len(integers)):

backtrack(i, target - integers[i], path + [integers[i]])

result = []

backtrack(0, N, [])

return result

# Test case

integers = [2, 3, 5]

N = 8

print(sum_to_n(integers, N))

• The sum_to_n function uses backtracking to find combinations of integers that sum to the target value N.
• The backtrack function recursively explores all possible combinations by iterating through the integers list and trying each integer as a candidate for the current combination.
• If the target value becomes 0, it means the combination sums up to N, so the current combination (path) is appended to the result list.
• If the target value becomes negative, or if we’ve reached the end of the integers list, the function returns without appending anything to the result.
• The function returns the result list containing all combinations that sum to N.

17. Explain the concept of continuous integration and continuous deployment (CI/CD).

The recruiter asks this question to evaluate your understanding of CI/CD principles. They are looking for your level of expertise in automating software development processes for faster and more reliable deployments.

How to answer

Define CI/CD as a software development practice that automates the process of integrating code changes into a shared repository (CI) and deploying code to production environments (CD) through automated pipelines.

Example

“CI/CD is a DevOps practice that enables automated testing, integration, and deployment of code changes. Continuous Integration involves automatically merging code changes into a shared repository, while Continuous Deployment automates the deployment of code changes to production environments after passing automated tests.”

18. Given a list of strings, write a Python program to check whether each string has all the same characters or not. What is the complexity of this program?

Example:

Input:

string_list = ['bbbbb', 'abc', 'aaaaaaaab']

Output: False

string bbbbb has all the same characters

string abc does not have all the same characters

string aaaaaaaab does not have all the same characters

How to answer

Here’s the Python program to check whether each string in the list has all the same characters or not, along with the explanation of its complexity:

def check_same_characters(string_list):

for string in string_list:

if len(set(string)) != 1:

print(f"String {string} does not have all the same characters")

return False

else:

print(f"String {string} has all the same characters")

return True

# Test case

string_list = ['bbbbb', 'abc', 'aaaaaaaab']

print(check_same_characters(string_list))

• The check_same_characters function iterates through each string in the list.
• It uses the set() function to convert the string into a set, which removes duplicate characters.
• If the length of the set is not equal to 1, it means the string has different characters, and the function returns False, indicating that the string does not have all the same characters.
• Otherwise, it prints a message indicating that the string has all the same characters.

The complexity of this program is O(n * m), where n is the number of strings in the list, and m is the length of the longest string. This is because the program iterates through each string and converts it to a set, which has a complexity of O(m).

19. What is the importance of version control in software development, and which version control system do you prefer?

The recruiter asks this question to evaluate your understanding of version control in software development. They want to know how much you are aware of version control in tracking changes, collaborating with team members, and ensuring code integrity.

How to answer

Explain the significance of version control in tracking changes, facilitating collaboration, and managing codebase history. Share your preference for version control systems like Git, SVN, or Mercurial, highlighting reasons for your choice.

Example

“Version control is crucial in software development for tracking changes, facilitating collaboration among team members, and maintaining a reliable history of codebase revisions. I prefer Git due to its distributed nature, branching model, and extensive community support.”

20. Given an array of words and a max_width parameter, write a function to format the text such that each line has exactly max_width characters. Pad extra spaces ’ ‘ when necessary so that each line has exactly max_width characters.

Note: Extra spaces between words should be distributed as evenly as possible. If the number of spaces on a line does not divide evenly between words, place excess spaces on the right-hand side of each line. You may assume that there is no word in words that is longer than max_width.

Example:

Input:

words = ["This", "is", "an", "example", "of", "text", "justification."]

max_width = 16

def justify(words, max_width): ->

[

"This    is    an",

"example  of text"