wxc's setup.hs currently fails to compile agaist Cabal 2. Normally that wouldn't be a problem, because the solver would pick a version of Cabal that is earlier than 2, but it has an incorrect custom-setup section that says that it works with any version of Cabal. Please add a < 2 upper bound to the Cabal dependency in setup-depends.
Related: https://github.com/haskell/cabal/issues/4683