Worked on the SciTools/iris repository to enhance the reliability of NetCDF calendar attribute handling by developing a round-trip integration test. This test verifies that calendar attributes are preserved accurately during save and load operations, directly addressing data integrity concerns and expanding the project’s testing coverage. The approach emphasized test-driven development using Python and NetCDF, ensuring that potential regressions are detected early in the development cycle. Additionally, documentation was updated to provide clearer guidance on calendar attribute handling, supporting both users and contributors. The work focused on integration testing, documentation practices, and robust validation of scientific data workflows within the codebase.