I don't get it. Wasn't this already released under MIT like two years ago?
It looks like this project skips the common intermediate language, and compiles straight to native processor code or Web Assembly (Ahead of Time compilation).
You get to skip the overhead of Just In Time compilation.
I think you are referring to MSIL
Using a much better compiler backend than NGEN, similar to Mono when targeting iOS.
Additionally, it is also adding WASM as target "CPU".
.NET Core only does JIT currently, the generated binary is a mini-bootstrap code that starts the runtime and feeds the main application Assembly into it.