Comment by woile

Slint-ui with rust (they have bindings for cpp, Python and js).

Quite good, I've been building this Pomodoro:

https://github.com/reciperium/temporis/

I've also used nix to build the packages when possible.

One of the things I like about slint is that it has native components. They also have experimental support for Android and iOS.

The language is quite simple as well. Though it could benefit from something like flex