Apologies in advance for the length of this email, but I've tried to be as clear as possible. Any help on the matter most appreciated. Goal: I have a simple interpreter for a language that I've written, and I wish to implement an FFI. My ideal api would be like 'ctypes' in python. Here's an example: from ctypes import * libc = CDLL("libc.so.6") libc.printf("An int %d, a double %f\n", 1234, c_double(3.14)) Prints out: An int 1234, a double 3.140000 Implementation: I am currently trying to use the dynamic linker in order to specify the library string, for example the following seems to work: import Foreign import Foreign.C.Types import Foreign.C.String import Monad (liftM) import System.Posix.DynamicLinker type Fun = CString -> IO CInt foreign import ccall unsafe "dynamic" c_printf :: FunPtr Fun -> Fun printf :: String -> IO Int printf str = do withDL "libc.so.6" [RTLD_NOW] $ \dl -> do printf_ptr <- dlsym dl "printf" let fun = c_printf printf_ptr liftM fromIntegral $ withCString str fun main = printf "hello world" Problem: I don't understand how I can generate the foreign import statements at runtime. I am currently considering generating strings of such expressions, and using hs-plugins in order to compile them. This seems like a complete hack though - I'm dynamically loading a haskell library in order to dynamically load a foreign library. Another option is to write a dynamic loader in C, and then call this from haskell, but how would I type the loading function - obviously I can give it a CString for the library, and another for the function in question - but what would the return type be? regards, Richard Warburton