diff --git a/crates/swc_compiler_base/src/lib.rs b/crates/swc_compiler_base/src/lib.rs
index 14291a9d581e..fdb82e773d78 100644
--- a/crates/swc_compiler_base/src/lib.rs
+++ b/crates/swc_compiler_base/src/lib.rs
@@ -270,7 +270,9 @@ where
     Ok(TransformOutput {
         code,
         map,
-        output: Some(serde_json::to_string(&output).context("failed to serilaize output")?),
+        output: output
+            .map(|v| serde_json::to_string(&v).context("failed to serilaize output"))
+            .transpose()?,
     })
 }