hm, so there's a topic I'm interested in reading existing research on, but I don't know exactly what to search for.

Specifically, I'm looking for examples of or research about visual programming languages where the for making gui programs, where the language is also the program's own UI. The only example that comes to mind for me right now is the one in Nintendo's Labo games.

@aeva
Smalltalk should fit, as should Racket. Perhaps Godot counts too, as someone mentioned.
@jannem none of these are visual programming languages

@aeva
Ah, you mean specifically Scratch and the like? Non-textual? Then no.

Scratch is the only visual language I know that's used at all - and arguably even Scratch is not 100% visual, as you still enter numbers and other parameters as text.

Also, the Scratch UI is not implemented in Scratch as far as I can tell. Are you sure the Nintendo UI is implemented in the user-level graphical system, and not a lower level thing?