diff --git a/pkgs/build-support/docker/default.nix b/pkgs/build-support/docker/default.nix
index 1f14bda203d..e2b03778bff 100644
--- a/pkgs/build-support/docker/default.nix
+++ b/pkgs/build-support/docker/default.nix
@@ -286,7 +286,9 @@ EOF
         cp ${layer}/* temp/
         chmod ug+w temp/*
 
-        touch layerFiles
+        # FIXME: might not be /nix/store
+        echo '/nix' >> layerFiles
+        echo '/nix/store' >> layerFiles
         for dep in $(cat $layerClosure); do
           find $dep >> layerFiles
         done