diff --git a/src/builders/rollup/stub.ts b/src/builders/rollup/stub.ts
index dbb9e8e..8fcdc21 100644
--- a/src/builders/rollup/stub.ts
+++ b/src/builders/rollup/stub.ts
@@ -145,7 +145,7 @@ export async function rollupStub(ctx: BuildContext): Promise<void> {
             resolvedEntry,
           )});`,
           hasDefaultExport
-            ? "\nexport default _module.default || _module;"
+            ? "\nexport default _module?.default ?? _module;"
             : "",
           ...namedExports
             .filter((name) => name !== "default")