17.5.2019 : Updated version of this article.
We are using Angular to build complex business application since the early version of AngularJS. While we love the framework and its rich ecosystem, we always struggled with the painful testing experience based on Jasmine and Karma. Our main pain points were the performance and the missing functionality to rerun only changed tests. With Jest, a testing platform from Facebook, these two points are solved in an elegant way and in addition it offers even more benefits.
This article shows how to configure your Angular application to integrate Jest. The article assumes that you are using an Angular CLI v7.3.x generated project from Angular v7.2.x. But it works too on earlier version of Angular projects.