Sarah Brolley refactored the State and StateDraft models in the commercetools/test-data repository, introducing new 'packed' and 'shipped' presets to align with an updated modeling pattern. She migrated model definitions, adjusted default values, and simplified type structures using JavaScript and TypeScript, focusing on improving reliability and maintainability of downstream data generation. Her work included updating the ignore file and adding changeset documentation to support changelog-driven releases. This targeted model migration reduced ambiguity in state handling and established a foundation for future extensibility. Over the month, Sarah demonstrated depth in model migration, refactoring, and testing within a TypeScript codebase.