On Fri, 11 Dec 2020, at 9:50 AM, Bardur Arantsson wrote:
(Dhall could work here since you can at least do inclusions and reuse in
a generic way. Plus it has fully defined semantics plus implementations
in at least a couple of langauges, Haskell and Scala.)

Psst https://hackage.haskell.org/package/dhall-to-cabal :)

I think the missing piece here is making a frontend that transparently turns Dhall to Cabal syntax and runs cabal-install, so you don't have to keep regenerating files.

Ollie