Worked on the streamlit/streamlit repository to address a regression affecting user login session persistence. Focused on backend development and session handling, the developer restored 30-day cookie lifetimes for st.login() by explicitly setting the Max-Age attribute in the Set-Cookie header using Python. This fix ensured users remained logged in across browser restarts, improving reliability and reducing support overhead. The solution involved reproducing the issue, implementing a targeted patch, and expanding automated and manual tests to validate the change. Collaboration with other contributors and thorough testing demonstrated attention to detail and a strong understanding of cookie management and authentication workflows.