diff --git a/pkgs/os-specific/linux/zfs/default.nix b/pkgs/os-specific/linux/zfs/default.nix
index 9b6c9b890cc..7e28a00300c 100644
--- a/pkgs/os-specific/linux/zfs/default.nix
+++ b/pkgs/os-specific/linux/zfs/default.nix
@@ -39,7 +39,7 @@ let
       patches = extraPatches;
 
       nativeBuildInputs = [ autoreconfHook nukeReferences ]
-         ++ optional (kernel != null) kernel.moduleBuildDependencies;
+         ++ optional buildUser kernel.moduleBuildDependencies;
       buildInputs =
            optionals buildKernel [ spl ]
         ++ optionals buildUser [ zlib libuuid python attr ]