diff --git a/src/lib.rs b/src/lib.rs
index c96c28a3..7517dd14 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -51,6 +51,7 @@
 //! We start by modelling the __state__ of our application:
 //!
 //! ```
+//! #[derive(Default)]
 //! struct Counter {
 //!     // The counter value
 //!     value: i32,