Automatically detect Stack Applications



Currently CircleCI automatically detects the presence of a *.cabal file for running tests, but it does not appear to detect stack.yaml, which indicates that the project uses Haskell Stack, a more recent build tool for Haskell projects.

Stack is gaining more ground due a nicer configuration, reproduceable builds, and automatic support for NixOs, Docker, and sandboxes. Supporting it out of the box would be nice.

Please note that Stack projects will still have a *.cabal file available. The presence of both indicates that the project should use stack and not cabal.


Hello @AshtonKemerling,

Thank you for your feedback! We’ve been considering ways to improve our inference, and will look into this in the future.

For now, I’ve moved this to our Feature Requests category so that our project managers can prioritize it.

Best, Zak


I campaigned, and got Stack v1.4.0 pre-installed in our latest image update:

Please give it a try and let us know if you run into any issues!