This is an interesting question, and one I did not directly address. One of the features of Rust is that it's practical to bind it to other languages, so I thin

This is an interesting question, and one I did not directly address. One of the features of Rust is that it's practical to bind it to other languages, so I think writing a "GUI engine" in Rust that's designed to play scripts in other languages is feasible. That said, it's not the main goal of the druid project. There, we're focusing on writing a real application in Rust. Dealing with language binding issues is hard, and anything that increases the scope too much puts the project at risk. So if you want a multi-language GUI toolkit written in Rust, asking me is not the way to get that, because I'm not going to build that. But if you want to be part of a community effort to build it, I'd be open to collaboration.