I've briefly looked at LLVM and how to interface with it but back then I didn't find much else than some C++ Builder API. I'd hope for some textual format that I could give to LLVM as an input. I assume it exists and that I've just been googling wrong :) Would definitely appreciate some pointers in that regard.

Other than that my best bet for native binaries is most likely compiling to C or GraalVM (which already exists as an experimental backend in elm-in-elm via Truffle!)