Jakub refactored the verification command in the foundry-rs/starknet-foundry repository, focusing on modularizing its implementation to improve maintainability and set the stage for future enhancements. He reorganized the verification logic by splitting it into subdirectories and introducing explorer and walnut verification interfaces, clarifying boundaries within the subsystem. This work preserved existing behavior while enabling safer and faster iteration of new features. Jakub applied his skills in Rust, code organization, and command line interface development to create a more extensible architecture, ensuring that future changes to the verification process can be implemented with greater ease and reduced risk of regressions.