Worked on the UKHO/erp-facade repository to deliver an end-to-end S100 SAP XML payload transformation feature, enabling integration with SAP systems. Focused on backend development using C# and XML transformation, the work included constructing XML payloads for S100 events and implementing robust logging to enhance observability and traceability of event flows. Expanded unit test coverage with NUnit and FakeItEasy to ensure reliability, while also performing code cleanup by removing obsolete event IDs to reduce technical debt. This approach improved production readiness for SAP integration and simplified future maintenance, demonstrating a methodical and test-driven engineering process throughout the development cycle.