diff --git a/product.version b/product.version
index 266146b87c..e20c784174 100644
--- a/product.version
+++ b/product.version
@@ -1 +1 @@
-1.6.3
+1.6.4-dev
diff --git a/tools/buildbot/build_type b/tools/buildbot/build_type
index 17640be702..38f8e886e1 100644
--- a/tools/buildbot/build_type
+++ b/tools/buildbot/build_type
@@ -1 +1 @@
-rel
+dev