During June 2026, this developer enhanced the symfony/symfony repository by implementing envelope-based recipient sourcing for the Microsoft Graph API transport within the Symfony Mailer Bridge. The update shifted recipient derivation from email headers to the envelope, reducing dependency on header content and enabling more flexible outbound recipient management. This approach improved compatibility with dynamic recipient lists and streamlined integration with Microsoft Graph API workflows. The work was delivered as a focused, traceable change, maintaining clear auditability through a single commit. PHP was used alongside skills in API integration, backend development, and unit testing to ensure maintainability and business value.