diff --git a/nixos/modules/services/networking/knot.nix b/nixos/modules/services/networking/knot.nix
index 89d3ea5e9626..145b4ad1dd3f 100644
--- a/nixos/modules/services/networking/knot.nix
+++ b/nixos/modules/services/networking/knot.nix
@@ -226,7 +226,7 @@ in {
       };
 
       settings = mkOption {
-        type = types.submodule { freeformType = types.attrs; };
+        type = (pkgs.formats.yaml {}).type;
         default = {};
         description = ''
           Extra configuration as nix values.