[Nix-dev] Using several versions of GHC at once

[Marc Weber]

Excerpts from Vladimír Čunát's message of Sat Jun 15 22:12:29 +0200 2013:
> Hmm, especially haskell packages are IMO better specified directly by 
> attribute. 

Not only those, See wiki "how to keep multiple packages up to date"
Again, hack-nix just solves it by allowing you to write a simple
configuration file which should contain both: cabal flags and an
optional non default ghc version.
You can have multiple of such configurations.

Well - do whatever works for you.

Marc Weber