diff --git a/tests/lib/default.nix b/tests/lib/default.nix
index 31b6b29d..0e8a3a35 100644
--- a/tests/lib/default.nix
+++ b/tests/lib/default.nix
@@ -1,5 +1,6 @@
 # For the environment-specific subset, we'll be simulating the configurations
 # as a simple attribute set since that's what they are anyways.
+{ pkgs ? import <nixpkgs> { } }:
 
 let
   inherit (pkgs) lib;