{ compiler, static ? false }:

self: super:
let
  lib =
    self.haskell.lib;

  overrides =
    final: prev:
    rec {
      protolude =
        prev.callHackageDirect
          {
            pkg = "protolude";
            ver = "0.3.0";
            sha256 = "0iwh4wsjhb7pms88lw1afhdal9f86nrrkkvv65f9wxbd1b159n72";
          } { };

      cabal2nix =
        if static then
        # cabal2nix depends on Cabal 3.0.*, while our pinned version of
        # Nixpkgs only provides 2.4 or 3.2. So we pinned 3.0.0.0 in
        # ./Cabal.nix
          prev.cabal2nix.overrideScope (self: super: { Cabal = self.callPackage ./Cabal.nix { }; })
        else
          prev.cabal2nix;
    };
in
{
  haskell =
    super.haskell // {
      packages = super.haskell.packages // {
        "${compiler}" =
          super.haskell.packages."${compiler}".override { inherit overrides; };
      };
    };
}