Stepan Fedunyak refactored the Libero processor in the huggingface/lerobot repository to improve type safety and maintainability for STATE feature handling. By replacing PipelineFeatureType with FeatureType, Stepan addressed type mismatches and standardized feature typing across the backend, reducing the risk of future regressions. The work involved targeted type fixes and enhancements to pre-commit hygiene, ensuring code quality and consistency throughout the data processing pipeline. Collaborating with other contributors, Stepan leveraged Python and backend development skills to deliver a more robust and scalable foundation for future features, demonstrating attention to maintainable engineering practices within a complex codebase.