React.js

ReactJS test: How it is structured and how it can help you hire your best candidate

Kandio’s ReactJS test lets you assess the candidates, employees, agencies, freelancers or students you have concerning any ReactJS task you might have.

Remember that Kandio offers guidelines on which programmers to proceed with, and which ones to discard. Kandio will give you reliable directions about things programmers should know about, but a programmer can be excellent, even if he does not know about all of these things.

We suggest that you use our tests before your interview process to know which ones actually to talk to. The final Kandio report should be a piece of conversation with the strong candidates, rather than a disqualifying process in a late-stage interview process.

ReactJS test details

React or ReactJS is a rapidly growing JavaScript library developed and maintained by Facebook. The use cases are growing as well as the support for the library as there are several strong advantages to utilizing React.

ReactJS is also the beating heart of React Native which is used throughout mobile development.

We hit up Yihua Zhang, which is one of the leading React consultants as well as one of the most successful instructors worldwide. Yihua created this test so you can get better and stronger candidates and at the same time, sign better employments with better people.

The ReactJS test consists of 20 challenging questions that Yihua believes are vital for a good React developer.

Who can benefit from this test?

1. Any company looking to build a web application in React can use this test.
2. Any hiring manager looking to assess a range of candidates within the vast React library.

The ReactJS test aims to help you evaluate if a candidate is aware of the pitfalls and complexities of using the basic building blocks of the React library. The test will also evaluate how well the candidate understands common architecture and coding patterns in React that are proven and tested to build scalable, maintainable and easy to work with React codebases.

¿Qué áreas (capítulos) se cubrirán en la prueba y por qué se eligió de esa manera?

Core Concepts
Knowing about React, a candidate must be familiar with how React works under the hood when it comes to updating the DOM. Candidates need to understand concepts like reconciliation, what the base React library can and cannot do, as well as how React as a library fits into the web development tool belt.

Flux Architecture
Flux architecture is the most commonly used high-level architectural pattern used with React. Massively popular libraries like Redux that are core parts of the React ecosystem have been used extensively to build some of the largest React products in the world. They all rely on a solid understanding of flux and how it fits into working with React.

Hooks
Nothing has shaken up the React community in recent years like the introduction of React hooks. React's core team is pushing hard for teams to replace a lot of the existing ways of building React applications over to a hooks based solution, so understanding how they work and what they do is important with the changing climate of React.

Component Behaviour
Components are the basic building blocks of React and they truly show how well a candidate understands React. Writing components represents almost 70% of what a developer will do in React, so a solid candidate needs to understand how these components work. An absolute must; how well candidates understand components determines how strong of a React developer they are.

Component Patterns
There are numerous patterns that can be used to build reusable components in React, but some are standard in the React ecosystem. There are numerous commonly used libraries in React that work off of these patterns. A solid understanding of what they are and their respective tradeoffs will show how well a candidate can write scalable and clean React code.

Performance
React can perform poorly if candidates do not understand how components are written, how React attempts to optimize for you, and what React specific pitfalls exist. Candidates should understand how to optimize the React code they write as well as when to optimize. We have included this in the ReactJS Test as it is essential to test how well a candidate understands how to build performant React applications.