---
id: architecture
title: Architecture
---

If you are interested in learning more about how Jest works, understand its architecture, and how Jest is split up into individual reusable packages, check out this video:

<iframe width="560" height="315" src="https://www.youtube.com/embed/3YDiloj8_d0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

If you'd like to learn how to build a testing framework like Jest from scratch, check out this video:

<iframe width="560" height="315" src="https://www.youtube.com/embed/B8FbUK0WpVU" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

There is also a [written guide you can follow](https://cpojer.net/posts/building-a-javascript-testing-framework). It teaches the fundamental concepts of Jest and explains how various parts of Jest can be used to compose a custom testing framework.
