{
  # Compares a generic dev shell with a Haskell-specific `shellFor` shell
  # while building the same local package in both cases.
  description = "Compare mkShell and shellFor";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
  };

  outputs =
    { self, nixpkgs, ... }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };
      haskellPackages = pkgs.haskellPackages.override {
        overrides = final: _: {
          mini-shell-choice = final.callCabal2nix "mini-shell-choice" ./. { };
        };
      };
      project = haskellPackages.mini-shell-choice;
      checkedProject = pkgs.haskell.lib.doCheck project;
      genericShell = pkgs.mkShell {
        packages = [
          haskellPackages.ghc
          pkgs.cabal-install
          pkgs.haskell-language-server
        ];
      };
      shellForShell = haskellPackages.shellFor {
        packages = hp: [ hp.mini-shell-choice ];
        nativeBuildInputs = [
          pkgs.cabal-install
          pkgs.haskell-language-server
        ];
      };
    in
    {
      packages.${system}.default = project;

      apps.${system}.default = {
        type = "app";
        program = "${self.packages.${system}.default}/bin/mini-shell-choice";
        meta.description = "Run the package used by both shell styles.";
      };

      devShells.${system} = {
        default = genericShell;
        generic = genericShell;
        shellFor = shellForShell;
      };

      checks.${system}.test-suite = checkedProject;
    };
}