[statictype]

I don't understand how the compiler's implementation language has any bearing on the design of the language it is trying to compile.

You should be able to write an O'Caml compiler in javascript or a Haskell compiler in C.

Rewriting the compiler in C# has the advantage of now being able to offer the compiler as a service to the C# run-time but not sure I see how it could have affected the design of the language.