diff --git a/caom2/setup.cfg b/caom2/setup.cfg
index 2d9b18c6..fa473373 100644
--- a/caom2/setup.cfg
+++ b/caom2/setup.cfg
@@ -39,7 +39,7 @@ edit_on_github = False
 github_project = opencadc/caom2tools
 install_requires = future lxml aenum six deprecated
 # version should be PEP386 compatible (http://www.python.org/dev/peps/pep-0386)
-version = 2.3.8.4
+version = 2.4.0a
 
 
 [entry_points]