diff --git a/docker/mailman/core/Dockerfile b/docker/mailman/core/Dockerfile
index 0abe1dbfbc..71c9952593 100644
--- a/docker/mailman/core/Dockerfile
+++ b/docker/mailman/core/Dockerfile
@@ -1,3 +1,4 @@
+# 2023-08-25T16:35:09 UTC - trigger rebuild
 # syntax = docker/dockerfile:1.3
 # Use 3.15 for Core since it has Python 3.9
 FROM alpine:3.18
diff --git a/zuul.d/infra-prod.yaml b/zuul.d/infra-prod.yaml
index c0e88125eb..48336bfb86 100644
--- a/zuul.d/infra-prod.yaml
+++ b/zuul.d/infra-prod.yaml
@@ -581,6 +581,7 @@
     vars:
       playbook_name: service-lists3.yaml
     files:
+      - docker/mailman
       - inventory/base
       - inventory/service/host_vars/lists01.opendev.org.yaml
       - playbooks/roles/iptables/