diff --git a/pyproject.toml b/pyproject.toml
index cfb8d4fd2..2694284b7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,7 @@ build-backend = "flit_core.buildapi"
 [project]
 # Check https://flit.readthedocs.io/en/latest/pyproject_toml.html for all available sections
 name = "pyconverter-xml2py"
-version = "0.3.dev0"
+version = "0.4.dev0"
 description = "PyConverter-XML2Py converter."
 readme = "README.rst"
 requires-python = ">=3.10,<4"