{ nix-filter, ... }:
final: prev: let
  src = nix-filter {
    root = ../.;
    include = [
      ../app
      ../src
      ../package.yaml
      # ../www-main.cabal
    ];
  };
in {
  haskellPackages = prev.haskellPackages.extend (hfinal: hprev: {
    www-main = hfinal.callCabal2nix "www-main" src {};
  });

  site = prev.symlinkJoin {
    name = "site";
    paths = [
      (final.haskell.lib.compose.justStaticExecutables final.haksellPackages.www-main)
      prev.rsync
    ];
  };
}