diff --git a/CHANGES.rst b/CHANGES.rst
index dd8333a0..75ddfa20 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,12 @@
 Changelog
 =========
 
+6.3.3 (unreleased)
+------------------
+
+- Nothing changed yet.
+
+
 6.3.2 (2024-05-07)
 ------------------
 
diff --git a/setup.py b/setup.py
index 5673062e..e1e166b9 100644
--- a/setup.py
+++ b/setup.py
@@ -4,7 +4,7 @@
 from setuptools import setup
 
 
-version = "6.3.2"
+version = "6.3.3.dev0"
 
 
 long_description = "\n\n".join(