Philipp Geier developed modernized API tooling and improved CI workflows across the ecmwf/metkit and ecmwf/downstream-ci repositories. He introduced a C++ wrapper for the ECCODES C API in metkit, providing a safer, object-oriented interface for GRIB/BUFR message handling with factory patterns and strongly typed enums. Philipp also fixed bitwise flag assignments in key iteration logic, enhancing reliability. In downstream-ci, he updated CI configurations to support the pymultio package and enabled parallel test execution, reducing feedback cycles. His work leveraged C++, Python, and CI/CD practices, demonstrating depth in low-level integration, robust error handling, and scalable software engineering for scientific data processing.