Craft CMS is a content management system for building bespoke websites.
Fly is a platform for running full stack apps and databases.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
Imgix is a visual media platform for managing, processing, rendering, optimising and delivering your existing images.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Plyr is a simple, lightweight, accessible and customizable HTML5, YouTube and Vimeo media player that supports modern browsers.
SEOmatic facilitates modern SEO best practices & implementation for Craft CMS 3.
Typekit is an online service which offers a subscription library of fonts.