AngularJS is a JavaScript-based open-source web application framework led by the Angular Team at Google.
Envoy is an open-source edge and service proxy, designed for cloud-native applications.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
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.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.