Worked on the FZJ-IEK3-VSA/FINE repository, delivering a focused refactor of the EnergySystemModel to improve code maintainability and readability. The main engineering effort involved extracting the time series data creation logic from the aggregateTemporally method into a dedicated helper function, ensuring the model’s behavior remained unchanged. This refactor introduced return type hints and comprehensive docstrings, while also updating formatting to comply with Ruff linting standards. Utilizing Python and Pandas, the changes enhanced modularity and future extensibility, reducing maintenance costs and making the codebase more accessible for new contributors and safer for ongoing enhancements to time series generation.