I think if I knew which libraries to add to the gcc link, I could make this work, but can't seem to find out from the documentation. Here are more specifics: I'd like to build a Cocoa program on OS X with the Aqua user interface using Xcode, but using a Haskell module with functions accessed through the foreign export interface. In fact this seems to fit in well with the Apple Model-View-Control programming pattern, with Haskell implementation of the Model, maybe some of the Control, and Cocoa implementation of the View and some of the Control. I've put together a short program (from the Wiki calling Haskell from C example) and compiling and linking with ghc it runs as advertised. As an experiment, I put the c main program into an Xcode project, added the haskell module .o and stub.o, stub.h files. Also added the HsFFI.h. Then did a build and run. As expected I got a bunch of missing entry points (26, if I recall correctly). Adding libffi.a and libHSrts.a brings me up to 56 missing entry points. Searching the other lib files for these seems pretty hopeless. Any pointers to documentation, or other help will be greatly appreciated! Thanks, John Velman