diff --git a/CHANGES.rst b/CHANGES.rst
index 2709e02..0f5e954 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -2,6 +2,12 @@ Changelog of fews-3di
 ===================================================
 
 
+3.4.2 (unreleased)
+------------------
+
+- Nothing changed yet.
+
+
 3.4.1 (2024-02-27)
 ------------------
 
diff --git a/pyproject.toml b/pyproject.toml
index c6697e9..629229f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -6,7 +6,7 @@ requires = ["setuptools>=69"]
 [project]
 name = "fews-3di"
 requires-python = ">=3.8"
-version = "3.4.1"
+version = "3.4.2.dev0"
 dependencies = [
   "netCDF4",
   "pandas",