Three Front-End Developer Interview Questions to Hire the Best Candidate

When you interview front-end developers, you need to test the candidate primarily for technical abilities. To make things easier for you ( vitamintalent.com/front-end-developer-interview-questions ), we have compiled a list of front-end developer interview questions to help you select the best candidate.

1. Can You Tell Us Two Programming Paradigms Important for JavaScript App Developers?

Java is a multi-paradigm programming language supporting functional, object-oriented and even imperative. The candidate should be able to explain prototypal inheritance and OLOO (object linked to other objects) pattern. Other things that can be part of the answer is an explanation of functional programming.

If the candidate doesn’t know what a paradigm is, consider it as a red flag.

2. What Is Asynchronous Programming and Why It Is Important?

Asynchronous programming is a way of parallel programming where a unit of the program runs separately from the main application thread and notifies the calling thread about its completion, progress, and failure. Asynchronous programming enables execution of concurrent operation using a single thread.

It is important because user interfaces spend a lot of time waiting for user input to trigger event handlers and interrupt event loop. Asynchronous programming allows the server to work normally (without interruption) and process one user request while other user requests follow.

The candidate needs to have an understanding of blocking and its performance implications. He/she also needs to have an understanding of event handling and its importance to UI code. It is one of the important front-end developer interview questions and if the candidate does not have knowledge about things mentioned above, consider it a red flag.

3. What Are the Pros and Cons of Microservices?

Each microservice has a specific job. Since microservices are of a decoupled nature, it is easier for a developer to reconfigure and recompose the microservice to serve different purposes of different apps. Developers can isolate hot services and scale them independently in the app.

One of the disadvantages of microservices is that a developer is more likely to discover cross-cutting concerns that were not anticipated at design time. The developer might have to develop separate modules to address cross-cutting concerns or enclose them in another container in other services layer from where all traffic is routed.

Since microservices are deployed on their own virtual machines, the front end developer might have to do a large number of Virtual Machines wrangling to manage different microservices in the app.

The candidate should have a basic understanding of working of microservices and their performance advantages. If the candidate is unaware of microservices ( https://vitamintalent.com/what-we-do ), its overhead and unable to decouple monolithic apps into microservices when needed, consider it as a red flag.

When you ask front-end developer interview questions, try to stick to high-level topics. If they are able to answer the above questions comfortably, it implies they have enough programming experience and can pick syntax and other new things pretty fast.

Do you have questions? Please feel free to leave your comments below.