AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Google Analytics is a free web analytics service that tracks and reports website traffic.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Open Graph is a protocol that is used to integrate any web page into the social graph.
RackCache is a quick drop-in component to enable HTTP caching for Rack-based applications.
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.