diff --git a/src/attr/__init__.py b/src/attr/__init__.py
index 9606d375..88f544bb 100644
--- a/src/attr/__init__.py
+++ b/src/attr/__init__.py
@@ -21,7 +21,7 @@ from ._make import (
 from ._version_info import VersionInfo
 
 
-__version__ = "20.4.0.dev0"
+__version__ = "21.1.0.dev0"
 __version_info__ = VersionInfo._from_version_string(__version__)
 
 __title__ = "attrs"