In November 2025, Alexander Neundorf contributed to the carbon-language/carbon-lang repository by developing a unit test to enhance C++ and Carbon interoperability, specifically targeting the 'using enum' feature. He implemented this test using C++ and Carbon, focusing on validating enum declarations and their correct import across language boundaries. His approach involved expanding the existing test scaffolding, which improved the reliability and coverage of interop scenarios and enabled faster iteration for future tests. Although this was his first contribution and did not involve bug fixes, Alexander demonstrated proficiency in C++ development, interoperability testing, and unit testing within a collaborative open-source workflow.