AngularJS and a new Service called Back& are eliminating the back-end/middleware. Taking the pieces of code that either interactive with databases or web services and moving them client side. This of course with the help of templating frameworks such as Mustache and Handlebars to handle page layouts and changing markup.
This movement seems to not only be pushing the evolution of ECMA script but also the tools around building these applications npm, node, grunt, bower.
From my experience though, his trend though did not start within the last 2 or even 3 years, but 8 years ago with the release of Sencha's ExtJS Version 2.0. ExtJS is a library/framework for building web applications, ExtJS has evolved quite a long way from version 2 to its current version 5 evolving into MVC framework and in its latest incarnation a MVVC framework. The end result for these client side frameworks are that you work with web services and data (JSON, XML).
Moving the front-end/middleware forward though can be risky, you cant just move all your backend/middleware code to the front-end, there are some security concerns that can play into this.
But with any luck this migration to the front-end will continue evolving and reduce the layers needs for creating complex websites, services and or applications.