cdnjs is a free distributed JS library delivery service.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
HTTP/3 is the third major version of the Hypertext Transfer Protocol used to exchange information on the World Wide Web.
Mailcheck is a JavaScript library designed to address the issue of misspelled email addresses during user input.
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.
PHP is a general-purpose scripting language used for web development.
Recurly provides enterprise-class subscription billing and recurring payment management for thousands of businesses worldwide.
Stripe offers online payment processing for internet businesses as well as fraud prevention, invoicing and subscription management.
WordPress.com is a platform for self-publishing that is popular for blogging and other works.