In Arch Linux, all haskell packages are dynamically linked. This can be a headache for the user, since it results in a large amount of haskell-* packages being installed on your system, and the possibility for version conflicts. A way around this is to not depend on pacman at all for haskell packages, but manually install them.
In this document I explain how I switched from a lot of haskell packages installed with pacman, to a few manually installed packages.
To determine which packages to uninstall (and replace), a few tools are useful:
pacmanitselfpacgraph