"I think part of the point of the exising layout is to fit within the existing filesystem heirarchy standard: non-executable data is stored in $prefix/share so that it can be mounted from a central server to multiple machines on multiple architectures, $prefix/bin is arch-specific etc. Making a new set of dirs under $prefix/haskell would mean that any existing shared environment would have to be modified just for haskell installs. Perhaps better would be $prefix/bin/haskell/... , $prefix/share/haskell/... etc." - Conrad Parker