Worked on the DFE-Digital/care-leavers repository to refine managed firewall rules, focusing on reducing false positives that interfered with Snapchat conversion tracking. Addressed an issue where the _ScCbts cookie, set at the education.gov.uk domain level, was being incorrectly blocked by Azure Front Door’s firewall due to its content and expiry. Using HCL and applying cloud security and firewall management expertise, implemented an exclusion for this cookie to maintain legitimate traffic flow while preserving the security posture. Documented the rationale for the change and ensured alignment with estate-wide cookie handling policies, supporting consistent infrastructure as code practices across the environment.