diff --git a/CHANGES.rst b/CHANGES.rst
index 35d4b4dd..f5137843 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,12 @@
 Changelog of threedigrid-builder
 ================================
 
+1.12.3 (unreleased)
+-------------------
+
+- Nothing changed yet.
+
+
 1.12.2 (2023-12-07)
 -------------------
 
diff --git a/threedigrid_builder/__init__.py b/threedigrid_builder/__init__.py
index 5ba57133..a51f6dd9 100644
--- a/threedigrid_builder/__init__.py
+++ b/threedigrid_builder/__init__.py
@@ -2,5 +2,5 @@
 from .exceptions import *  # NOQA
 
 # fmt: off
-__version__ = '1.12.2'
+__version__ = '1.12.3.dev0'
 # fmt: on