diff --git a/lass/source.nix b/lass/source.nix
index 910d70334..36210423b 100644
--- a/lass/source.nix
+++ b/lass/source.nix
@@ -10,7 +10,7 @@ in
       nixos-config.symlink = "stockholm/lass/1systems/${name}/config.nix";
       nixpkgs.git = {
         url = https://github.com/nixos/nixpkgs;
-        ref = "c99239b";
+        ref = "ac2bb56";
       };
       secrets.file = getAttr builder {
         buildbot = toString <stockholm/lass/2configs/tests/dummy-secrets>;