Stripe Software Engineer Interview Guide

This is an initial call with the recruiter, which would typically be an informal chat. You will discuss your experiences, your background, etc. You can ask the recruiter various questions such as the different roles at the company, and what is expected of you if you join the company.

The recruiter will also schedule the next round i.e., the technical screening round.

• What do you know about Stripe?
• Where do you see Stripe?
• What about Stripe makes you want to work here?
• What are your career aspirations?
• Talk about a project you’re most proud of.

This will be a video call with someone from the team, most likely an engineer. It will typically be a 1-hour interview. The first 5-10 minutes will be utilized in introductions, and then you will be required to share your screen and do live coding in the language of your choice. 

The interviewer will typically ask only one question but will have many follow-up questions. Test cases will be provided and you will have to code the solution such that the tests pass. 

Depending on the time left, you may also have a general chat with the interviewer.

Note - The interview is designed to be of a pair-programming type, where your "pair" will be the interviewer.

The coding questions will test the following topics - 

• System Design
• Databases
• Heaps
• Data Structures

In some cases, you can have 2 technical interviews instead of the usual one. It will follow a format similar to the first one.

• The language of the problem can be a bit complicated, but don’t lose hope. Generally, complicated-looking questions have the easiest solutions, so re-read the question till you have clarity, and you’ll be able to solve it. 
• Focus on writing good code i.e. readable (with proper indentations), and easy to understand (few comments to explain the procedure, and in a logical arrangement). 
• The interviewer wants to understand your thought process, so it’s okay to check in with them on syntax. You may be allowed to refer to Google or any documentation for syntax, but it’s better to check in with the interviewer first.
• Practice interviews in pair programming format so that you’re able to understand the flow of the round.

• Print all nodes less than a given value x from the min-heap.
• Given a sample database, write the unit tests to cover all cases.
• Create a database class for a given problem. 
• Design a method to find the minimum value in a given column of the given database.
• Design a function from a given database. 
• Design a data structure that can store a unique data type. 

Note - Simple questions based on if/else conditions, parsing, and arrays can also be asked.

This is the final round of interviews. It generally consists of 5 interviews (in no particular order) which take place over a period of 3-4 hours -

• Coding interview
• Behavioral round with Hiring Manager
• Bug hunt
• System Design 
• Problem Solving/Integration Task

Before the onsite, you will receive a preparation guide to know what to expect and what to practice for. 

1. Coding interview  

This interview will test your coding skills and proficiency in data structures.

Sample Questions - 

• Using a given list of maps and keys, return the lowest corresponding value among the maps. 
• Given some values, generate the sets of values whose sum is X.

Note - Questions based on databases and heaps can also be asked.

2. Behavioural Round with Hiring Manager

This will consist of leadership-oriented and behavioral-type questions. 

Tips - 

• Follow the STAR method to answer the questions - Situation, Task, Action, Result, and focus on the result.

Sample questions - 

• What is something you would have done differently in a project?
• Discuss a time when you disagreed with a team decision. What did you do about it? 
• Talk about a time when you had to resolve a difficult situation within the team.
• Tell me about a time you made a mistake. What did you learn from it? 

3. Bug Hunt

In this round, you will be given a codebase, and you’ll have to run various tests to identify the bug(s) in the program and provide the most accurate fix. You will be provided with resources such as a failing test to help identify the bugs. You will have to complete the entire process in a given amount of time. 

Note - Generally, the bugs are easy to recognize and fix. What makes the task difficult is the code. It may be difficult to understand the code due to a lack of comments and advanced coding components that are rarely used. 

4. System Design

In this round, you will be required to design a system. This round aims to assess how you build a large-scale system, your thought process, and what information you take into account while designing it.

Tips -

• Clarify all doubts with the interviewer before you start designing the system. You may also be required to make assumptions, so it’s best to let the interviewer know.
• The interviewer wants to know your approach towards the problem, so think aloud. Explain every step and how you arrived at that step.

Sample questions - 

• Design a database for a product such as a toy.
• Design the frontend and backend for a logging system.
• Design an architecture for delivering webhooks to customers.
• Design a notification system that can deal with a huge amount of traffic. 
• Sketch out the high-level design of a large system for a large company. 

5. Integration Task

In this round, you will be required to integrate new code into an existing codebase. You must be familiar with HTTP Rest calls, parsing JSON, and sending requests to APIs.