elixir-lang/elixir — pull request #2079 by ericmj (2014-02-28 16:44:21+00:00)
Title: Add `:only` dep option to filter on environments

mix deps.get will by default fetch all deps unless --only flag is given.

Closes https://github.com/elixir-lang/elixir/issues/2038.

We should update getting started guide with this.