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

  outputs = { self, nixpkgs }: let
    system = "x86_64-linux";
    pkgs = nixpkgs.legacyPackages.${system};
  in {
    bigint-lib = pkgs.callPackage ./lib.nix { };
    packages.${system}.default = with self.bigint-lib; pkgs.writeText "bigint-test" (let
      toS' = x: if builtins.isBool x
                  then if x
                    then "true"
                    else "false"
                  else if isBigInt x then bigIntToString x
                  else toString x;
      compare = name: f: x: y: "${name} ${bigIntToString x} ${bigIntToString y} = ${toS' (f x y)}";
    in ''
      ${bigIntToString (toBigInt 123)}
      ${bigIntToString (toBigInt (-123))}
      ${bigIntToString (toBigInt (-0))}
      ${bigIntToString (toBigInt 0)}

      ${compare "bigIntEquals" bigIntEquals (toBigInt (0)) (toBigInt (1))}
      ${compare "bigIntEquals" bigIntEquals (toBigInt (-1)) (toBigInt (1))}
      ${compare "bigIntEquals" bigIntEquals (toBigInt (2)) (toBigInt (2))}
      ${compare "bigIntEquals" bigIntEquals (toBigInt (0)) (toBigInt (-0))}

      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt 0) (toBigInt 0)}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt 12345) (toBigInt 9999)}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt 9999) (toBigInt 12345)}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt 99999) (toBigInt 12345)}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt (-99999)) (toBigInt 12345)}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt 99999) (toBigInt (-12345))}
      ${compare "bigIntGreaterThan" bigIntGreaterThan (toBigInt (-99999)) (toBigInt (-12345))}

      ${compare "bigIntLessThan" bigIntLessThan (toBigInt 0) (toBigInt 0)}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt 12345) (toBigInt 9999)}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt 9999) (toBigInt 12345)}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt 99999) (toBigInt 12345)}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt (-99999)) (toBigInt 12345)}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt 99999) (toBigInt (-12345))}
      ${compare "bigIntLessThan" bigIntLessThan (toBigInt (-99999)) (toBigInt (-12345))}

      ${compare "bigIntAdd" bigIntAdd (toBigInt 0) (toBigInt 0)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 1) (toBigInt 2)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 1) (toBigInt (-2))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 5) (toBigInt (-10))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-2)) (toBigInt 1)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-10)) (toBigInt 5)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 100000000) (toBigInt (-1))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-1)) (toBigInt 100000000)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 200000000) (toBigInt (-2))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-2)) (toBigInt 200000000)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 99) (toBigInt 99)}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-1)) (toBigInt (-2))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-99)) (toBigInt (-99))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (99)) (toBigInt (-99))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-99)) (toBigInt (99))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt (-99)) (toBigInt (99))}
      ${compare "bigIntAdd" bigIntAdd (toBigInt 100000000) (toBigInt 1)}

      ${compare "bigIntSub" bigIntSub (toBigInt 0) (toBigInt 0)}
      ${compare "bigIntSub" bigIntSub (toBigInt 1) (toBigInt 2)}
      ${compare "bigIntSub" bigIntSub (toBigInt 100000000) (toBigInt (-1))}
      ${compare "bigIntSub" bigIntSub (toBigInt (-1)) (toBigInt 100000000)}
      ${compare "bigIntSub" bigIntSub (toBigInt 200000000) (toBigInt (-2))}
      ${compare "bigIntSub" bigIntSub (toBigInt (-2)) (toBigInt 200000000)}
      ${compare "bigIntSub" bigIntSub (toBigInt 99) (toBigInt 99)}
      ${compare "bigIntSub" bigIntSub (toBigInt (-1)) (toBigInt (-2))}
      ${compare "bigIntSub" bigIntSub (toBigInt (-99)) (toBigInt (-99))}
      ${compare "bigIntSub" bigIntSub (toBigInt (99)) (toBigInt (-99))}
      ${compare "bigIntSub" bigIntSub (toBigInt (-99)) (toBigInt (99))}
      ${compare "bigIntSub" bigIntSub (toBigInt (-99)) (toBigInt (99))}

      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 0) (toBigInt 0)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 100) (toBigInt 0)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 100) (toBigInt 1)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 100) (toBigInt 2)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 100) (toBigInt 100)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 1) (toBigInt 2)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 100000000) (toBigInt (-1))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-1)) (toBigInt 100000000)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 200000000) (toBigInt (-2))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-2)) (toBigInt 200000000)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt 99) (toBigInt 99)}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-1)) (toBigInt (-2))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-99)) (toBigInt (-99))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (99)) (toBigInt (-99))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-99)) (toBigInt (99))}
      ${compare "bigIntMultiply" bigIntMultiply (toBigInt (-99)) (toBigInt (99))}
    '');
  };
}