diff --git a/layer0/Version.h b/layer0/Version.h
index 46f69c642..33f377b92 100644
--- a/layer0/Version.h
+++ b/layer0/Version.h
@@ -1,5 +1,5 @@
 #ifndef _PyMOL_VERSION
-#define _PyMOL_VERSION "3.0.0"
+#define _PyMOL_VERSION "3.1.0a0"
 #endif
 
 /* for session file compatibility */