diff --git a/CHANGELOG.md b/CHANGELOG.md
index 608f0cb00..6426ff287 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,8 @@
 # Change Log
 All notable changes to this project will be documented in this file. This project adheres to [Semantic Versioning](http://semver.org)
 
+## 4.0.4-dev
+
 ## 4.0.3 - 2025-09-11
 
 ### Added
diff --git a/config/constants.yml b/config/constants.yml
index 92c19886d..b2cebc1c7 100644
--- a/config/constants.yml
+++ b/config/constants.yml
@@ -7,7 +7,7 @@
 ---
 
 # App
-TERMINUS_VERSION: '4.0.3'
+TERMINUS_VERSION: '4.0.4-dev'
 
 # Connectivity
 TERMINUS_HOST:        'terminus.pantheon.io'