Worked on the metno/pyaerocom repository to enhance the robustness of the Colocator component, focusing on improving error handling, metadata consistency, and the reliability of CAMS2_83 data parsing. Applied Python and data processing skills to refactor code, update test fixtures, and clarify test assertions, which reduced the risk of ingestion failures and shortened debugging cycles. Strengthened the unit testing suite by dedenting multiline strings and cleaning up test logic, resulting in more stable and maintainable tests. These efforts improved data integrity and maintainability, enabling more reliable downstream analytics and supporting faster issue diagnosis within the data processing pipeline.