Valerie Din developed a new date and time difference operator for the Meaningful-Data/vtlengine repository, expanding its data transformation capabilities. She implemented the datediff operator using Python, focusing on robust parsing, validation, and evaluation logic to accurately compute durations between date or time values. Valerie integrated the operator within the existing backend framework and ensured reliability through comprehensive unit testing. Her work addressed the need for precise analytics by enabling accurate duration calculations, supporting downstream data engineering tasks. The project demonstrated depth in backend development and operator implementation, with maintainable code and clear validation coverage that improved analytics reliability.