Ayelet centralized the Stateful Validator Trait within the Blockifier crate in the starkware-libs/sequencer repository, moving it from the apollo_gateway crate to streamline cross-crate validation logic. This refactor involved updating feature flags and mock capabilities to ensure compatibility and maintainability across the codebase. By focusing on code organization, crate management, and trait definition in Rust, Ayelet reduced duplication and clarified crate responsibilities, laying a stronger foundation for future stateful validation work. The changes improved testability and maintainability, enabling more consistent validation logic throughout the sequencer. No major bugs were addressed during this period, reflecting a focused engineering effort.