Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google Publisher Tag (GPT) is an ad tagging library for Google Ad Manager which is used to dynamically build ad requests.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Mailchimp is a marketing automation platform and email marketing service.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
OneSignal is a customer engagement messaging solution.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
A modest JavaScript framework for the HTML you already have.
Typekit is an online service which offers a subscription library of fonts.