cdnjs is a free distributed JS library delivery service.
Google Analytics is a free web analytics service that tracks and reports website traffic.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Phusion Passenger is a free web server and application server with support for Ruby, Python and Node.js.
Pinterest is an image sharing and social media service designed to enable saving and discovery of information.
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
Typekit is an online service which offers a subscription library of fonts.