NodeJS Interview Guide 100+ Questions & Answers

Node.js architecture, file system API, http, Express.js, databases, REST, GraphQL, microservices, system design and more

Interviews can be quite stressful. For some reason, you often freeze or struggle to verbalise the concepts with which you work on the daily basis. Although you have enough coding and design knowledge, you might not be as efficient presenting this knowledge as using it in your projects.

Preparation is the best type of effort you can put in, to put your best foot forward in an interview setting. Apart from coding skills, you also need to be able to verbalise the concepts you work with and be able to clearly articulate how they work and what problems they address.

This is where this course comes in. I gathered 100+ actual Node.js interview questions either I personally received or my colleagues did. Although I wouldn't do bad answering those in the actual interview, I often left out important details. Especially when asked about intimate knowledge of how Node.js operates and what makes it so good for the web, database related questions and some good practices around working with them and many more. Here's a glimpse of some of the more important topics covered in this course:

• Node.js event loop

• Cluster mode (+ PM2), Child Process and Worker Threads

• NPM dependencies

• stubbing, spying and mocking in testing

• Buffer & Stream for working with data

• pitfalls of streams when working with a lot of data

• data streaming in Node.js

• designing data contracts and http responses

• REST v GraphQL

• CommonJS v ES Modules

• webserver building blocks - middleware, interceptor, router, controller, service

• relational v non-relational databases

• database migrations

• SQL anti-patterns

• multi-stage Dockerfiles

• managing tasks in distributed multi-pod microservice

• how to mitigate risk of SQL injection

• and MUCH more!

This course is meant to prepare you for such questions by going as deep as needed into each concept, understanding the context of questions, understanding the underlying technology used to address the problem asked by the interviewer and providing clear recommendations. In the end, there are no perfect solutions, there are just trade-offs. To find the right solution, you need to understand those trade-offs.

I know I will be using this course to prepare for my Node.js interviews. I also plan on adding new questions from my own interviews and others’. I would love to add yours too!

Another valuable resource is course repository with running code examples for a lot of questions. That’s the playground where theory meets practice. Each example is a standalone recipe on how to use a component or pattern in practice.

I am not saying this course is going to make you a Node.js expert. But I'm also not saying it won't.