At Beamery we had a large, AngularJS app, built over several years. Our clients were happy, but we were not. We had several problems: Building new features was slow. AngularJS doesn’t scale nicely. Features clash with each other. Isolation doesn’t come as standard, you have to work hard to keep features separate. It takes time to get it right. #Hiring was hard, for all the reasons listed above. The app was slower than it needed to be because AngularJS was never built for speed. We wanted to render half a million contacts, and Angular was fighting us all the way.
As time went by it become harder to find developers who would willingly choose AngularJS over React Angular 2 , Vue.js , Aurelia or Polymer .
So we faced a choice. We could throw it all away and start again, we could upgrade to Angular 5, or the awesome option - we could use micro frontends. We chose the awesome option.