diff --git a/src/dependency_injector/__init__.py b/src/dependency_injector/__init__.py
index 71177d5c..cfc06647 100644
--- a/src/dependency_injector/__init__.py
+++ b/src/dependency_injector/__init__.py
@@ -1,6 +1,6 @@
 """Top-level package."""
 
-__version__ = '4.0.0a1'
+__version__ = '4.0.0a2'
 """Version number.
 
 :type: str