diff --git a/.github/workflows/container.yaml b/.github/workflows/container.yaml
index b98634b..f1ccada 100644
--- a/.github/workflows/container.yaml
+++ b/.github/workflows/container.yaml
@@ -21,8 +21,12 @@ jobs:
       # Go hard on the builders
       max-parallel: 5
       matrix:
-        alpine-version: ['3.21', '3.20']
+        alpine-version: ['3.20', '3.19']
         ruby-version: ['3.3.6', '3.3.5', '3.3.4']
+        # Only 3.3.6 is published (to docker.io) for 3.21, so we include only that here.
+        include:
+          - alpine-version: '3.21'
+            ruby-version: '3.3.6'
     steps:
       -
         name: Checkout repository