This is a Heroku buildpack for Haskell apps. It uses GHC 7.4.1 and cabal-1.16.0.1.
I build this new version of the buildpack to run a slighty newer Yesod version than 1.1.2; currently I only tested it with yesod-1.1.9.
$ ls
Procfile app.cabal src
$ heroku create --stack=cedar --buildpack https://github.com/ichistmeinname/heroku-buildpack-haskell.git
$ git push heroku master
...
-----> Heroku receiving push
-----> Fetching custom git buildpack... done
-----> Haskell app detected
-----> Downloading GHC
######################################################################## 100.0%
-----> Downloading Cabal
######################################################################## 100.0%
-----> Setting up ghc-pkg
...