What is described in article is a subset of Haskell: "...as long as one is writing mostly vanilla Haskell you can’t tell the difference." And then it proceeds

What is described in article is a subset of Haskell: "...as long as one is writing mostly vanilla Haskell you can’t tell the difference." And then it proceeds to tell us that you can't tail recurse. Mu is different language which uses Haskell ecosystem. What I am interested in and what article does not tell is how big the actual Mu compiler is. I think it is in the hundreds of thousands of lines of code, 200K SLOC or more. And it is still a big code base and it's use of Haskell is success.