Feature request: GNU Guix integration

I'm sure that, as I do, a lot of people want to develop Haskell programs on Guix.

I see Stack has a Nix integration. Since Guix is based on Nix, there should be possible to create an integration for it as well. Right now, when using Stack (for example to install something), it fails saying it can't find the `ldconfig` executable. I don't know what you've done for Nix, but I think some of the principles used for it can apply to Guix as well.

A `stack` package definition for Guix would be nice too, but I think that request would fit better on Guix's own mailing lists.