Amazon Pay is an online payments processing service that is owned by Amazon. It lets you use the payment methods associated with your Amazon account to make payments for goods and services.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
Modernizr is a JavaScript library that detects the features available in a user's browser.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
PHP is a general-purpose scripting language used for web development.
Shopware is an enterprise-level ecommerce platform.
A modest JavaScript framework for the HTML you already have.