htmx gives you access to AJAX, CSS Transitions, WebSockets and Server Sent Events directly in HTML, using attributes, so you can build modern user interfaces with the simplicity and power of hypertext

Create components that render fragments of HTML and compose them to create screens, pages, documents, or apps.

S5 is a slide show format based entirely on XHTML, CSS, and JavaScript. With one file, you can run a complete slide show and have a printer-friendly version as well