I was wondering how to forcibly quiet down the API. I have a custom handler in place, but when I call the function on failure both my handler gets called and somewhere somehow errors get printed to the stderr, which I really need to avoid. My current code looks like getModInfo :: Bool -> String -> String -> IO (ApiResults ModuleInfo) getModInfo qual file path = handleSourceError processErrors $ runGhc (Just libdir) $ do dflags <- getSessionDynFlags setSessionDynFlags $ configureDynFlags dflags target <- guessTarget file Nothing addTarget target setSessionDynFlags $ dflags { importPaths = [path] } load LoadAllTargets graph <- depanal [] False let modifier = moduleName . ms_mod modName = modifier $ head graph includes = includePaths dflags imports = importPaths dflags dflags' <- Debug.trace (moduleNameString modName) getSessionDynFlags setSessionDynFlags $ dflags' { includePaths = path:includes , importPaths = path:imports } parsed <- parse modName checked <- typecheckModule parsed