Hello Thorkil, I updated the wiki Replacing GMP/The Current GMP Implementation page with some introductory notes. I hope the pretty graphic cuts down on a lot of wording necessary. There is no discussion of the Cmm implementation as that is contained in Esa's posts to the GHC users list or in the PrimOps pages in the new Commentary. (Maybe I should move the GMP->Cmm->Haskell discussion into The Current GMP Implementation page but I really have to get some honest coding done.) Cheers, Peter