Folks, Would there be support for splitting off the MonadIO class from the mtl, and simple having Control.Monad.Trans re-export it? My proposed packaging of the functionality is here: http://community.haskell.org/~aslatter/code/monad-io Here's my problem which prompted this: I'm converting a library of mine over to the failure[1] package for returning errors, and the type on a lot of my functions is as follows: (MonadFailure MyFailureType m, MonadIO m) => Alpha -> Beta -> m Gamma The MonadFailure constraint is defined separate from its many instances, which would give the consumers of my library the choice between using the mtl or the transformers[2] library. Except that I also need a MonadIO constraint, for which I must pick from which package I choose it. Antoine [1] http://hackage.haskell.org/package/failure