Used [this configuration][dr-hakyll] to integrate with CircleCI. [dr-hakyll]: http://www.stackbuilders.com/news/dr-hakyll-create-a-github-page-with-hakyll-and-circleci
$ git clone https://github.com/stackbuilders/dr-hakyll
$ cabal sandbox init
$ cabal install --only-dependencies
$ cabal configure
$ cabal build
$ cabal run build
$ cabal run watch