[rapsey]

Libui is kind of dead and so limited I am surprised people still bother with projects like this.

[cmroanirgo]

The README kind of addresses this:

> if there is only a need to build a small simple application, Glimmer DSL for LibUI could be a good convenient choice due to having zero prerequisites beyond the dependencies included in the Ruby gem. Also, just like Glimmer DSL for Tk, its apps start instantly and have a small memory footprint.

[gompertz]

And glancing at the screenshots, that look can be achieved in FLTK which is lightweight, active, and been around decades.

[mvladic]

Correct if I'm wrong, but FLTK is not using native widgets so it is not the same thing.