diff --git a/ports/stm32f4/mpconfigport.mk b/ports/stm32f4/mpconfigport.mk
index 985c4a18ae..93b22dc6af 100644
--- a/ports/stm32f4/mpconfigport.mk
+++ b/ports/stm32f4/mpconfigport.mk
@@ -20,6 +20,7 @@ CIRCUITPY_DIGITALIO = 1
 CIRCUITPY_ANALOGIO = 1
 CIRCUITPY_MICROCONTROLLER = 1
 CIRCUITPY_BUSIO = 1
+CIRCUITPY_OS = 1
 
 #ifeq ($(MCU_SUB_VARIANT), stm32f412zx)
 #endif