diff --git a/compose/__init__.py b/compose/__init__.py
index c550f990..6e610652 100644
--- a/compose/__init__.py
+++ b/compose/__init__.py
@@ -1,4 +1,4 @@
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
-__version__ = '1.8.0'
+__version__ = '1.9.0dev'