---
title: Introduction to the Quality Assurance with Chai Challenges
block: quality-assurance-and-testing-with-chai
superBlock: quality-assurance
---

## Introduction to Quality Assurance with Chai Challenges

As your programs become more complex, you need to test them often to make sure any new code you add doesn't break the program's original functionality. Chai is a JavaScript testing library that helps you check that your program still behaves the way you expect it to after you make changes. Using Chai, you can write tests that describe your program's requirements and see if your program meets them.

Working on these challenges involves writing code on Replit in our starter project.

- Start by importing the project on Replit.
- Next, you will see a <code>.replit</code> window.
- Select <code>Use run command</code> and click the <code>Done</code> button.
- Complete each challenge and copy the public Replit URL (to the homepage of your app) into the challenge screen to test it!

Optionally, you may write your project on another platform, but it must be publicly visible for our testing.

Start this project on Replit using [this link](https://replit.com/github/freeCodeCamp/boilerplate-mochachai) or clone [this repository](https://github.com/freeCodeCamp/boilerplate-mochachai/) on GitHub! If you use Replit, remember to save the link to your project somewhere safe!
