cdnjs is a free distributed JS library delivery service.
Cowboy is a small, fast, modular HTTP server written in Erlang.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
PerimeterX is a provider of scalable, behavior-based threat protection technology for the web, cloud, and mobile.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
Varnish is a reverse caching proxy.