Fastly is a cloud computing services provider. Fastly's cloud platform provides a content delivery network, Internet security services, load balancing, and video & streaming services.
GitHub Pages is a static site hosting service.
Google Analytics is a free web analytics service that tracks and reports website traffic.
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.
Shopify is a subscription-based software that allows anyone to set up an online store and sell their products. Shopify store owners can also sell in physical locations using Shopify POS, a point-of-sale app and accompanying hardware.
Varnish is a reverse caching proxy.