diff --git a/src/common/Version.hxx b/src/common/Version.hxx
index 1f2f2e6a0..f10389d9a 100644
--- a/src/common/Version.hxx
+++ b/src/common/Version.hxx
@@ -18,7 +18,7 @@
 #ifndef VERSION_HXX
 #define VERSION_HXX
 
-#define STELLA_VERSION "6.5"
+#define STELLA_VERSION "6.6_pre"
 #define STELLA_BUILD "6673"
 
 #endif