diff --git a/roles/saltmaster/software/files/staging-commit-message.py b/roles/saltmaster/software/files/staging-commit-message.py
new file mode 100755
--- /dev/null
+++ b/roles/saltmaster/software/files/staging-commit-message.py
@@ -0,0 +1,95 @@
+#!/usr/bin/env python3
+
+#   -------------------------------------------------------------
+#   Staging :: write a commit message for submodule update
+#   - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+#   Project:        Nasqueron
+#   Created:        2018-10-27
+#   License:        Trivial work, not eligible to copyright
+#
+#   Thanks to joki for the git diff-files and ls-tree hint
+#   https://stackoverflow.com/a/52908906/1930997
+#   -------------------------------------------------------------
+
+
+from git import Repo
+from os import path
+import re
+import subprocess
+
+
+staging_repo_path = '/opt/salt/staging'
+
+
+class SubmoduleCommit:
+
+    def __init__(self, repo_path, submodule_path):
+        self.repo_path = repo_path
+        self.submodule_path = submodule_path
+        self.repo = Repo(self.submodule_path)
+
+    def craft_commit(self):
+        lines = []
+
+        old_hash = self.get_old_hash()
+        new_hash = self.get_new_hash()
+
+        lines.append("Bump " + path.basename(self.submodule_path)
+                     + " to " + new_hash[:12])
+        lines.append("")
+        lines.extend(self.get_commits_lines(old_hash, new_hash))
+
+        return "\n".join(lines)
+
+    def get_old_hash(self):
+        output = subprocess.check_output(['git', 'ls-tree',
+                                          '@', self.submodule_path],
+                                         cwd=self.repo_path,
+                                         encoding="utf-8")
+        matches = re.search('.*commit ([a-f0-9]*).*', output.strip())
+        return matches.group(1)
+
+    def get_new_hash(self):
+        return str(self.repo.head.commit)
+
+    @staticmethod
+    def format_commit_line(commit):
+        commit_hash = str(commit)[:12]
+        title = commit.message.split("\n")[0]
+
+        return "    * {} {}".format(commit_hash, title)
+
+    def get_commits_lines(self, hash_base, hash_head):
+        commits_lines = []
+
+        for commit in self.repo.iter_commits(hash_head):
+            if str(commit) == hash_base:
+                break
+
+            line = self.format_commit_line(commit)
+            commits_lines.append(line)
+
+        return commits_lines
+
+    def has_submodule_been_updated(self):
+        process = subprocess.run(['git', 'diff-files', '--quiet',
+                                  self.submodule_path],
+                                 cwd=self.repo_path)
+        return process.returncode != 0
+
+
+def run(repo_path):
+    repo = Repo(repo_path)
+
+    submodules = [SubmoduleCommit(repo_path, submodule.name)
+                  for submodule in repo.submodules]
+
+    commits = [submodule.craft_commit()
+               for submodule in submodules
+               if submodule.has_submodule_been_updated()]
+
+    print("\n\n".join(commits))
+
+
+if __name__ == "__main__":
+    run(staging_repo_path)
diff --git a/roles/saltmaster/software/init.sls b/roles/saltmaster/software/init.sls
--- a/roles/saltmaster/software/init.sls
+++ b/roles/saltmaster/software/init.sls
@@ -6,7 +6,7 @@
 #   License:        Trivial work, not eligible to copyright
 #   -------------------------------------------------------------
 
-{% from "map.jinja" import packages_prefixes with context %}
+{% from "map.jinja" import dirs, packages_prefixes with context %}
 
 #   -------------------------------------------------------------
 #   Additional software
@@ -17,3 +17,10 @@
     - pkgs:
       # Jenkins execution module
       - {{ packages_prefixes.python3 }}python-jenkins
+      # For staging-commit-message
+      - {{ packages_prefixes.python3 }}GitPython
+
+{{ dirs.bin }}/staging-commit-message:
+  file.managed:
+    - source: salt://roles/saltmaster/software/files/staging-commit-message.py
+    - mode: 755