Worked on the actualbudget/actual repository to deliver Hanseatic Bank support within the GoCardless integration, focusing on expanding payment-method coverage and improving maintainability. Implemented a dedicated configuration file for Hanseatic Bank and integrated it through the bank factory, enabling scalable onboarding of additional banks. Addressed compliance by enforcing an 89-day access window, aligning with GoCardless constraints and project requirements. Utilized JavaScript for backend and full stack development, emphasizing API integration and modular configuration. The approach enhanced reliability and positioned the product for future growth, reflecting a methodical engineering process that prioritized maintainability and adaptability in a complex financial integration context.