Sarah Keller focused on improving test reliability and maintainability for the metrotranscom/doorway repository during July 2025. She refactored the public site header by removing dynamic indices from data-testid attributes, which simplified Cypress end-to-end test selectors and reduced test brittleness. This technical approach enhanced the stability of automated testing and supported faster, more reliable CI feedback cycles. Working primarily with JavaScript and TypeScript, Sarah applied her expertise in front end development and testing to address maintainability concerns. The depth of her work is reflected in the targeted refactor, which directly addressed a known issue and improved the overall testing workflow.