diff --git a/src/lib.rs b/src/lib.rs
index 07ad71d..f8e81f0 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -178,6 +178,7 @@
 //! use serde_json::{json, to_string};
 //!
 //! let org = Org::parse("I 'm *bold*.");
+//! #[cfg(feature = "ser")]
 //! println!("{}", to_string(&org).unwrap());
 //!
 //! // {