diff --git a/src/lib_wasm.rs b/src/lib_wasm.rs
index ac9229a57e..13d6ca66da 100644
--- a/src/lib_wasm.rs
+++ b/src/lib_wasm.rs
@@ -86,6 +86,7 @@ pub fn defaultSettings() -> Result<JsValue, JsValue> {
     Ok(serde_wasm_bindgen::to_value(&Options {
         // Propagate defaults.
         allowed_confusables: Some(Vec::default()),
+        builtins: Some(Vec::default()),
         dummy_variable_rgx: Some("^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$".to_string()),
         extend_ignore: Some(Vec::default()),
         extend_select: Some(Vec::default()),