diff --git a/flix/prefs.h b/flix/prefs.h
index 3044108..487daa9 100644
--- a/flix/prefs.h
+++ b/flix/prefs.h
@@ -1,4 +1,4 @@
-#ifdef ESP32
+#ifndef ARDUINO_ARCH_STM32
 #include <Preferences.h>
 #else