diff --git a/include/ethosu_driver.h b/include/ethosu_driver.h
index 2594fbe..433ad06 100644
--- a/include/ethosu_driver.h
+++ b/include/ethosu_driver.h
@@ -77,6 +77,12 @@
 };
 
 /******************************************************************************
+ * Variables
+ ******************************************************************************/
+
+extern struct ethosu_driver ethosu_drv;
+
+/******************************************************************************
  * Prototypes
  ******************************************************************************/