CodeIgniter4 Viewi Demo

htmx and viewi have different architectures.
So you need to decide which is better for you.

If htmx is enough for you, it might be better. 
It is supported by many organizations, and used in the world.
See https://risingstars.js.org/2023/en#section-framework
and there is a HTMX helper library for CI4.
https://github.com/michalsn/codeigniter-htmx

Viewi compiles PHP code into JavaScript code, 
and of course works with CI4.

I recommend you try both, and compare.

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