diff --git a/CHANGELOG.md b/CHANGELOG.md
index f36cbc2..dfe7191 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 3.9.4
+
+* Use ruby 3.4 as base docker image
+
 ## 3.9.3 - 2025-10-07
 
 * Don't use a composite if DBAGENT_DATABASES is present but empty
diff --git a/Dockerfile b/Dockerfile
index 2f3abba..71264d8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:3.3
+FROM ruby:3.4
 
 ENV LANG C.UTF-8
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]