Worked on the Shopify/shopify_app repository to enhance the security and reliability of the authentication process by focusing on robust JWT handling and token validation. Developed a method to safely extract shop information from JWTs, reinforcing the login workflow and reducing edge-case failures during user authentication. Addressed issues with invalid tokens in redirection header processing, improving the overall user experience. The work involved updating the changelog and simplifying tests to reflect new behaviors, making ongoing maintenance more efficient. Utilized Ruby and Markdown while applying skills in API integration, authentication, and backend development to deliver a safer, more maintainable login system.