[Haskell-cafe] Cabal + gfortran?

Hi, I want to set up a build that compiles fortran sources in addition to the Haskell, and which maybe also eventually checks for the existence of a library or two (specifically, LAPACK and BLAS). Does anyone here have a suggestion for where I should be looking to figure out how to do this, such as a package which uses such a setup that would provide an example? Thanks, Greg