Htmx 4 is a modern JavaScript library that enables developers to build dynamic web applications using HTML attributes instead of heavy frameworks.
It introduces key improvements like the Fetch API for better performance, explicit attribute inheritance for predictability, and a simplified history model for reliability.
The library followes a hypermedia-driven approach, allowing servers to return HTML fragments for partial page updates.
Its extension-based architecture keeps the core lightweight while enabling advanced features like WebSockets and SSE.
Security is strengthened through reduced client side complexity, CSP compatibility, and proper handling of user input, making htmx 4 efficient, scalable, and developer-friendly.
More info - <a href="https://medium.com/@anubhavbhatt/whats-new-in-htmx-4-features-architecture-security-deep-dive-fceacb9f8399" target="_blank" rel="noopener nofollow">What’s new in HTMX</a>

Anubhav Bhatt

HTMX 4 brings several notable improvements to the hypermedia-driven web library. Key changes include adoption of the Fetch API for better performance, explicit attribute inheritance for more predictable behavior, and a simplified history model. The extension-based architecture keeps the core lightweight while supporting advanced features like WebSockets and Server-Sent Events. Security is also improved through reduced client-side complexity, CSP compatibility, and better input handling.

HTMX 4 concepts and features