Buildpack for gigalixir app's that use Mix.
For releases, see https://github.com/gigalixir/gigalixir-buildpack-releases
For distillery, see https://github.com/gigalixir/gigalixir-buildpack-distillery
To use this, see https://gigalixir.readthedocs.io/en/latest/modify-app/mix.html#specify-buildpacks-optional