Another option (C++ LGPL w/ Lua,JS bindings): https://github.com/yue/yue
Other projects building on andlabs/ui and https://github.com/parro-it/libui-node:
Other projects building on andlabs/ui and https://github.com/parro-it/libui-node:
It allows to build the whole UI using HTML, CSS and JS and leverage it with all the tooling and libraries already built for the web.