diff --git a/ampel-firmware/util.h b/ampel-firmware/util.h
index e5a73262c26750606f4a6babf7650333b22dedb2..5b0ac8040d222caced367f92bad7b12ab013acbd 100644
--- a/ampel-firmware/util.h
+++ b/ampel-firmware/util.h
@@ -26,7 +26,7 @@ class Ampel {
 private:
   static void showFreeSpace();
 public:
-  const char *version = "v0.3.0"; // Update manually after significant changes.
+  const char *version = "v0.3.1-DEV"; // Update manually after significant changes.
   const char *board;
   const char *sensorId;
   const char *macAddress;