Hello, I uploaded new release of bindings-gobject, low level binding to gobject library: http://hackage.haskell.org/package/bindings-gobject-0.4 (I maintain it now) Now it exposes internals of GObject and GObjectClass, so it is possible to create custom GObject subclasses from haskell land. Source repository contains basic example: https://github.com/Yuras/bindings-gobject/blob/master/examples/custom-object... The use case I'm personally is interested in is implementing custom SourceCompletionProvider for gtksourceview2. I hope it will be useful for other applications. Right now we don't (afaik) have low level bindings to gtk and gtksourceview. But once we will have them, it will be possible to create custom controls in haskell and even expose them to C (C++, python, etc) land. Thanks, Yuras