diff --git a/images/5-edge/Dockerfile b/images/5-edge/Dockerfile
index 6534870..347b9aa 100644
--- a/images/5-edge/Dockerfile
+++ b/images/5-edge/Dockerfile
@@ -1,4 +1,4 @@
-FROM php:8.3-apache
+FROM php:8.4-rc-apache
 
 # install persistent PHP extensions (they won’t get purged afterwards)
 RUN set -eux; \
diff --git a/source/images.yml b/source/images.yml
index 2273c89..2bf4416 100644
--- a/source/images.yml
+++ b/source/images.yml
@@ -20,4 +20,4 @@ images:
       - "5-edge"
     package-url: "https://github.com/redaxo/redaxo/releases/download/5.17.1/redaxo_5.17.1.zip"
     package-sha: "75b8e5a7e58b8c80cacdbd19f6cce8653d3f4d50"
-    php-version: "8.3"
+    php-version: "8.4-rc"