Hello, In a project of mine I needed an Applicative instance for Identity and noticed it didn't exist. So I decided to add Applicative (and Alternative instances where possible) for all MTL types. When I was about to submit a library proposal I saw there already existed one. So I added my patch to that ticket. My patch I different in that my Applicative instances don't require a Monad constraint. This also means that most Functor instances now also depend on Applicative rather than on Monad. See the ticket for the details: http://hackage.haskell.org/trac/ghc/ticket/2316 Discussion period: 5 weeks (taking the holidays into account) This is the old thread about this proposal: http://thread.gmane.org/gmane.comp.lang.haskell.libraries/9140/focus=9154 regards, Bas