diff --git a/CHANGES.rst b/CHANGES.rst
index 7025ca7..c674849 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,12 @@
  Changes
 =========
 
+3.0.4 (unreleased)
+==================
+
+- Nothing changed yet.
+
+
 3.0.3 (2023-12-21)
 ==================
 
diff --git a/src/greenlet/__init__.py b/src/greenlet/__init__.py
index 298a19d..a708889 100644
--- a/src/greenlet/__init__.py
+++ b/src/greenlet/__init__.py
@@ -25,7 +25,7 @@
 ###
 # Metadata
 ###
-__version__ = '3.0.3'
+__version__ = '3.0.4.dev0'
 from ._greenlet import _C_API # pylint:disable=no-name-in-module
 
 ###