Mention Ansible Role in README.md

* Improve garbage collector cronjob to limit find on files (ignore
  directories).

README.md

@@ -56,10 +56,21 @@ systemctl restart nginx/apache/…
 
 It should now be working.
 
-You should add `find /var/www/mat2-web/uploads/* -mtime +1 -exec rm {} \;`
+You should add `find /var/www/mat2-web/uploads/ -type f -mtime +1 -exec rm {} \;`
 in a crontab to remove files that people might have uploaded but never
 downloaded.
 
+# Deploy via Ansible
+
+If you happen to use Ansible, there's an Ansible role to deploy mat2-web on
+Debian: [ansible-role-mat2-web](https://github.com/systemli/ansible-role-mat2-web)
+
+The role install mat2-web as uWSGI service (run as dedicated system user),
+installs bubblewrap for mat2 sandboxing and creates a garbage collector
+cronjob to remove leftover files . Besides, it supports to create a dm-crypt
+volume with random key for the uploads folder in order to protect the uploaded
+files.
+
 # Threat model
 
 - An attacker in possession of the very same file that a user wants to clean,