Worked on the SuperGoodSoft/solidus repository to enhance the accuracy of line item total calculations by refactoring tax handling logic. Focused on backend development using Ruby, the work involved isolating tax computations within the Spree::ItemTotal class to address discrepancies between included and additional taxes, as well as adjustments marked for destruction. This refactoring improved maintainability and ensured that tax compliance and billing integrity were upheld, reducing the risk of revenue leakage from miscalculations. The approach emphasized object-oriented design and careful refactoring, laying a foundation for more robust tax logic across order processing within the codebase.