I hate to be a bit blunt but you're really barking up the wrong tree.

VSCode debugger works fine on both msvc and mingw targets.

Asking for COM or UWP is like saying that Javascript has a horrible interop story with COM/UWP. You're picking Rust to build something fast and/or low memory. Leave building a UI to the right tools.

C# has a fantastic FFI and works just fine with Rust. I actually have a project using UWP and Rust together. I get all the portability of Rust and get to use UWP as the UI frontend with minimal fuss.

I am just raising awareness, it is all a matter if you feel like it matters to earn the hearts of. Windows developers using to their VS, C# + C++ and respective tooling productivity.

Picking up your example,how do you expose and debug UWP components?

Those are probably what the parent means by "UI framework." The Rust toolchain does integrate seamlessly with those platforms' native toolchains, using the same binary and debug info formats.

Perhaps this is perception is just caused by e.g. the extremely low bar set by MinGW, which doesn't do any of that despite "supporting" Windows.

Those stacks are more than just UI.

For example since Longhorn failure, COM has become the major way to introduce Windows APIs, since Vista Win32 doesn't get much love.