diff --git a/mdbook/src/11-uart/reverse-a-string.md b/mdbook/src/11-uart/reverse-a-string.md
index c3dabbc..fe34ba7 100644
--- a/mdbook/src/11-uart/reverse-a-string.md
+++ b/mdbook/src/11-uart/reverse-a-string.md
@@ -24,7 +24,6 @@ use microbit::{
     hal::uarte::{Baudrate, Parity},
 };
 
-mod serial_setup;
 use serial_setup::UartePort;
 
 #[entry]