diff --git a/default.nix b/default.nix
index b3ebe5511..593162c5a 100644
--- a/default.nix
+++ b/default.nix
@@ -1,5 +1,5 @@
 
-{ pkgs }:
+{ pkgs ? import <nixpkgs> {} }:
 let
   inherit (pkgs) fetchgit fetchFromGitHub callPackages;
 in {
diff --git a/nur/update.py b/nur/update.py
index 449e2bd68..05bb48aa4 100755
--- a/nur/update.py
+++ b/nur/update.py
@@ -154,7 +154,7 @@ def generate_nix_expression(repos: List[Repo]) -> str:
     joined = "\n\n".join(expressions)
 
     return f"""
-{{ pkgs }}:
+{{ pkgs ? import <nixpkgs> {{}} }}:
 let
   inherit (pkgs) fetchgit fetchFromGitHub callPackages;
 in {{