diff --git a/modules/config.xqm b/modules/config.xqm
index d9d1ec51..ed0a75c2 100644
--- a/modules/config.xqm
+++ b/modules/config.xqm
@@ -188,10 +188,11 @@ declare function config:pocom-people-last-modified() as xs:dateTime {
 declare variable $config:PUBLICATIONS :=
     map {
         "app": map {
-            "publication-last-modified": max((
-                config:last-modified-from-repo-xml($config:app-root),
-                config:last-modified-from-repo-xml($config:CAROUSEL_COL)
-            ))
+            "publication-last-modified": function () {
+                  max((
+                    config:last-modified-from-repo-xml($config:app-root)(),
+                    config:last-modified-from-repo-xml($config:CAROUSEL_COL)()
+                ))}
         },
         "frus": map {
             "collection": $config:FRUS_COL_VOLUMES,