diff --git a/CHANGELOG.md b/CHANGELOG.md
index 34aa826..6f4e5c1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,7 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 To see unreleased changes, please see the [CHANGELOG on the master branch](https://github.com/gufolabs/gufo_acme/blob/master/CHANGELOG.md) guide.
 
-## [Unreleased]
+## 0.4.0 - 2023-11-23
 
 ## Added
 
diff --git a/src/gufo/acme/__init__.py b/src/gufo/acme/__init__.py
index 9e7549f..c866f57 100644
--- a/src/gufo/acme/__init__.py
+++ b/src/gufo/acme/__init__.py
@@ -17,4 +17,4 @@
 * [log][gufo.acme.log] - Logging utilities.
 * [types][gufo.acme.types] - Package public types.
 """
-__version__ = "0.3.0"
+__version__ = "0.4.0"