HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Htmx is a JavaScript library for performing AJAX requests, triggering CSS transitions, and invoking WebSocket and server-sent events directly from HTML elements.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Unpkg is a content delivery network for everything on npm.
Vercel is a cloud platform for static frontends and serverless functions.