diff --git a/src/usb/hid/hid.c b/src/usb/hid/hid.c
index 155c743..f5b55aa 100644
--- a/src/usb/hid/hid.c
+++ b/src/usb/hid/hid.c
@@ -15,6 +15,7 @@
  * along with this program. If not, see <https://www.gnu.org/licenses/>.
  */
 
+#include <stdio.h>
 #include "picokeys.h"
 #include "serial.h"
 #include "pico_time.h"