diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..a875063
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,13 @@
+# Changelog
+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](https://git.d3data.de/D3Public/sensitiveMessageFormatter/compare/1.0.0...rel_1.x)
+
+## [1.0.0](https://git.d3data.de/D3Public/sensitiveMessageFormatter/releases/tag/1.0.0) - 2024-12-23
+### Added
+- initial implementation
+    - replace defined fixed strings by replacement characters
+    - search for urlencoded strings too