Nail the Back-End Engineering Interview

What to Expect at Back-End Engineering Interviews

Generally, the interview process for back-end engineers is divided into the following segments:

Recruiter screening

The hiring recruiter will contact you by phone to discuss his or her work experience. The recruiter will determine which roles you are qualified for based on your work experience. Knowing which projects and experiences you want to talk about before going into the interview can be helpful.

After going through this round, you should receive a follow-up email from the recruiter that will include an online technical assessment.

Online assessment

This interview is an online screening of your programming skills. You will have about 90 minutes to complete three coding challenges similar to Leetcode. In each challenge, you will be tested on data structures and algorithms. It is important that you write compiling code and pass the majority of the test cases shown in the UI.

To prepare for this round, you should:

Be thorough with data structures and algorithms in a particular language (IE python, java, etc.)
Revise space and time complexities
Practice problems online on websites like Leetcode

Final interview stage

This round consists of 4-6 interviews of one-hour each. These rounds are as follows:

2- 3 technical programming interviews
1-2 system design interview
One behavioral interview

Technical Programming Interviews

These interviews will each consist of one programming challenge, where you will be given a coding challenge similar to the ones in the online assessment, but this time with an actual SDE.

The challenges will test your knowledge of data structures, algorithms, and OOP. During the problem-solving stage, you will be asked about test cases, time/space complexity, and ways to improve the solution.

Using an online coding practice website like Leetcode to prepare for the back-end engineer interview questions on tech programming can be extremely beneficial. While practicing, make sure to include questions about algorithms, data structures, and object-oriented programming.

System Design Interview

This section will be with a Hiring Manager or principal engineer who will test your system design skills. An example of a system design question could be “Design Instagram,” in which you should:

Dive into the requirements and assumptions
Layout the architecture
Define some databases
Define some APIs
Define performance-related parts of your design

This section is about designing the software rather than coding it. However, depending on the problem, you may have to pseudo-code at times.

To prepare for the back-end engineer interview questions on system design, you should practice software design. You should understand servers, caching, performance-related topics, databases, APIs, etc.

Behavioral Interview

A “Bar Raiser” conducts this back-end engineer interview on behavioral skills, which is primarily about the experience and how one can relate to specific behavioral topics and scenarios. In an Amazon interview, for example, you will be asked behavioral questions about their leadership principles, and the interviewer will assess whether or not your answers align with the company’s values.

You should prepare for this section by understanding Amazon’s 16 Leadership Principles and how your experience relates to them. Also, when you are explaining your solution, try to use the STAR (situation, task, action, and result) method to break down your answer.

Final decision

After the final round of back-end engineer interview questions, you should hear back within two weeks. During the interview, your technical skills and behavioral responses will be compared to the technical competencies of the role, as well as the principles of the company, to see if you’re a good fit.

To clear the tough interviews at the top tech companies globally, you’ll need to have the right skills. Read 7 Back-end Developer Skills You Must Have to Crack Tech Interviews and start getting ready!

Back-End Engineering Interview Questions

Back-end developer interview questions for beginners evaluate the basic understanding of different programming languages. The difficulty level of questions keeps increasing as per your experience level. Advanced back-end engineering interview questions are focused on the framework of back-end development, technologies, languages, etc.

The back-end engineer developer questions can be classified into three buckets:

Back-End Engineering Interview Questions on Coding

Given the root node of a binary tree, clone it (clone every node of the tree) and return the root node of the cloned tree.

Given a binary tree and an integer k, find all the root to leaf paths that sum to k.

Given a set of integers and a target value k, find whether there is a non-empty subset that sums up to k.