### default.nix ###
{ nixpkgs ? import <nixpkgs> { config.allowUnfree = true; }
, compiler ? "default"
, doBenchmark ? false
}:

let
  inherit (nixpkgs) pkgs;

  thepackage = import ./thepackage.nix;

  haskellPackages = if compiler == "default"
                       then pkgs.haskellPackages
                       else pkgs.haskell.packages.${compiler};

  variant = if doBenchmark then pkgs.haskell.lib.doBenchmark else pkgs.lib.id;
in
  variant (haskellPackages.callPackage thepackage {})



### shell.nix ###
{ nixpkgs ? import <nixpkgs> { config.allowUnfree = true; }
, compiler ? "default"
, doBenchmark ? false
}:

let
  inherit (nixpkgs) pkgs;
  drv = import ./default.nix { inherit nixpkgs compiler; };
  drvWithTools = pkgs.haskell.lib.addBuildDepends drv (with pkgs; [
    cabal-install haskellPackages.ghcid
  ]);
in
  if pkgs.lib.inNixShell then drvWithTools.env else drvWithTools