The first project has a business requirement for what I would call near real-time components, and the components need to be embedded into an Open Atrium site. Another future need was to allow these components to be embeddable in other business sites and use cases, so this led the architecting of a Node.js set of APIs that provide the server-side rendered React.js components and JSON data endpoints to provide data to these components after they are instantiated, rendered and embedded.
The second project is a very tech-forward website, that is using Drupal 8 for the content management and on the front-end many data sevices that will feed Angular 2 based web components. After following what the Angular team’s blog’s and podcast conversations recently, there is a clear architectural paradigm that is surfacing (Redux style data flow and state management). A good write-up of this type of architecture is located at this blog post.