Developed a country-aware customer login feature for the Shopify/hydrogen repository, enabling region-specific login experiences while maintaining compatibility with existing authentication flows. The implementation introduced a countryCode parameter supporting all ISO 3166-1 alpha-2 codes, aligning with multi-region strategies and enhancing localization for international users. Leveraging TypeScript and full stack development skills, the work focused on robust API integration and ensured that merchants could onboard new regions without disruption. The approach emphasized code hygiene, clear commit messaging, and traceability, resulting in a non-breaking change that supports analytics readiness and immediate multi-region deployment for e-commerce platforms using hydrogen.