I built a custom CMS (Later named to DolphinCMS) using Angular 6, Firebase (AngularFire), Bootstrap 4, ngx-bootstrap, Angular Material Design, Robotron (Serverside rendering), and more. The site will be visited by tens of thousands of people, with over a dozen active CMS users. I built 99% of the site. I received some help with CSS as a result to meeting a deadline. The CMS uses Roboton for serverside rendering (SEO, Graph QL).
I used two way data-binding for instant page editing feedback for CMS users (seen in image). The CMS comes with image/file uploading, Meta update areas, a email/contact ticketing system, and much much more.