diff --git a/src/create.ts b/src/create.ts
index b8c140e..eba24ba 100644
--- a/src/create.ts
+++ b/src/create.ts
@@ -114,7 +114,7 @@ export function createArchiveByFileExtensionOrThrow(
 	if (!a) {
 		throw new Error(`Unsupported archive format: ${path}`);
 	}
-	return null;
+	return a;
 }
 
 /**