htmx extends HTML as a hypertext, it isn't tied to any particular backend and doesn't have any binding concepts. It's really a complete different concept.
I think htmx scales up and down pretty well: web developer newbs who don't want to sink a ton of time into a JS framework, as well as veteran web developers who want to stick with hypertext for the majority of their web apps.
HTMX encodes server interaction in hypertext rather than in Javascript. For those with intensive back-end logic and only light interface needs, HTMX offers a incremental way to add front-end interactivity without having to take the deep dive into Javascript frameworks. Longer term, the concept of encoding server interaction in hypertext seems rather novel to me. Perhaps this approach may be one of many missing pieces towards an ecosystem of interoperable hypertext-based web components?
In our agency augmented HTML (Htmx/Intercooler, AlpineJS, etc.) is very useful for web designers, they can go further with interactions and behaviors while staying in a HTML/CSS environment. Also it helps a lot in the communication between the design and developer teams, because there is a lot more understanding of what's going on.
That's great to hear and one of the big benefits to an HTML-first architecture: it's much easier to understand the entire stack, for feature development as well as optimization.
