During April 2025, this developer focused on backend security within the plone/plone.restapi repository, addressing a critical issue in the Schema Serializer. They identified and resolved a bug where protected fields could be exposed due to incorrect permission checks. By implementing permission caching directly on the serializer instance and updating all relevant permission check sites, they ensured proper access control and reduced the risk of unauthorized data exposure. Their work leveraged Python and backend development skills, with an emphasis on security and caching patterns. This fix not only improved data protection but also contributed to the maintainability and reliability of the API.