I have a little application that makes use of the hsqml library. This library hasn't been updated too recently, and so has dependency constraints that exclude the current stack LTS version. I worked around it by using a local copy of the library and manually editing the constraints in hsqml.cabal and verifying that everything still worked as expected.

It appears that cabal-install supports an --allow-newer flag to support just this use case. Does stack? I could not find it in the "in-depth guide" (which is great!) or the stack.yaml wiki page.

If it isn't supported, could it? What would be necessary for this? I'd be willing to work on it.