I guess very close alternative to Goey will be GioUI [0]. It is really simple in the implementation, so it also covers many platforms as targets [1]. However, that is also a problem - there aren't many prepared components as in Qt or SwiftUI, no "native" feel of mouse or clipboard handling. One of the example of app I have found in the Internet is GUI for the password-store [2].
[0]: https://gioui.org/