Sawyer contributed to the stripe/stripe-js repository by delivering two well-scoped features focused on internationalization and frontend customization. In April 2025, Sawyer expanded the Payment Method Messaging Element to support additional currencies and country codes, updating TypeScript definitions and improving test reliability by removing hardcoded values. Later, in August, Sawyer enhanced the Appearance interface by introducing a customizable buttonBorderRadius type, enabling more flexible theming for UI elements. Both features were implemented using TypeScript and required careful API development to ensure backward compatibility. Sawyer’s work demonstrated depth in both internationalization and frontend development, addressing real-world usability and maintainability concerns.