diff --git a/composer.json b/composer.json
index aee3979..38523c7 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,8 @@
     "require": {
         "php": ">=7.4",
         "symfony/console": "^6.3",
-        "symfony/process": "^6.3"
+        "symfony/process": "^6.3",
+        "panlatent/cron-expression-descriptor": "^1"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.5"
diff --git a/scripts/cms5/merge-ups.php b/scripts/cms5/merge-ups.php
new file mode 100644
index 0000000..9eb8414
--- /dev/null
+++ b/scripts/cms5/merge-ups.php
@@ -0,0 +1,51 @@
+<?php
+
+// run 3 days offset from when a weekly CI run is, otherwise run on a random day of the week
+$runOnDay = rand(0, 6);
+// run at the same hour as the weekly CI run, otherwise run at a random hour of the day
+$runOnHour = rand(0, 23);
+// run at the same minute as the weekly CI run, otherwise run at the top of the hour
+$runOnMinute = 0;
+
+if (check_file_exists('.github/workflows/dispatch-ci.yml')) {
+    $ci = read_file('.github/workflows/dispatch-ci.yml');
+    preg_match("#- cron: '(.+?) (.+?) (.+?) (.+?) (.+?)'#", $ci, $matches);
+    [$_, $minute, $hour, $day, $month, $dayOfWeek] = $matches;
+    if ($dayOfWeek !== '*') {
+        $days = explode(',', $dayOfWeek);
+        $runOnDay = ($days[count($days) - 1] + 3) % 7;
+    }
+    if ($hour !== '*') {
+        $hours = explode(',', $hour);
+        $runOnHour = $hours[0];
+    }
+    if ($minute !== '*') {
+        $runOnMinute = $minute;
+    }
+}
+
+$cron = "$runOnMinute $runOnHour * * $runOnDay";
+$humanCron = human_cron($cron);
+$account = module_account();
+
+$content = <<<EOT
+name: Merge-up
+
+on:
+  # $humanCron
+  schedule:
+    - cron: '$cron'
+  workflow_dispatch:
+
+jobs:
+  merge-up:
+    name: Merge-up
+    # Only run cron on the $account account
+    if: (github.event_name == 'schedule' && github.repository_owner == '$account') || (github.event_name != 'schedule')
+    runs-on: ubuntu-latest
+    steps:
+      - name: Merge-up
+        uses: silverstripe/gha-merge-up@v1
+EOT;
+
+write_file_if_not_exist('.github/workflows/merge-ups.yml', $content);