diff --git a/CHANGES.rst b/CHANGES.rst
index 09f0da7..59da8c7 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,12 @@ Changelog of fews-3di
 ===================================================
 
 
+3.5 (unreleased)
+----------------
+
+- Nothing changed yet.
+
+
 3.4.3 (2024-02-28)
 ------------------
 
diff --git a/pyproject.toml b/pyproject.toml
index a0a5b2a..4118627 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,7 +6,7 @@ requires = ["setuptools>=69"]
 [project]
 name = "fews-3di"
 requires-python = ">=3.8"
-version = "3.4.3"
+version = "3.5.dev0"
 dependencies = [
   "netCDF4",
   "pandas",