Worked on enhancing the gem_rbs_collection repository by introducing typing support for Devise authentication in Ruby on Rails applications. Focused on developing comprehensive type definitions and interfaces for Devise methods and modules, this work improved static type checking for authentication flows within ActiveRecord models. Leveraged skills in Ruby, gem development, and type definitions to establish new metadata and test configurations, supporting ongoing type-safety validation. The approach consolidated type interfaces to streamline maintainability and facilitate future refactoring of authentication logic. These contributions laid a foundation for safer integrations and reduced runtime errors, emphasizing robust engineering practices and forward-looking code organization.