diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3475bf..f5b45a8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [UNRELEASED] - XXXX.XX.XX
+## [v0.9.0-alpha] - 2024.09.09
 
 ### Added
 
diff --git a/src/kspdg/__init__.py b/src/kspdg/__init__.py
index 802567c..19cfadd 100644
--- a/src/kspdg/__init__.py
+++ b/src/kspdg/__init__.py
@@ -5,7 +5,7 @@
 # Single-sourcing package version
 # https://packaging.python.org/guides/single-sourcing-package-version/
 
-__version__ = "0.8.1"
+__version__ = "0.9.0-alpha"
 
 # these imports make the individual environments accessible at the top-level
 # of the library and assign an environment version number