Worked on stabilizing subscription routing logic in the Gozargah/Marzban repository, focusing on compatibility with Python 3.12. Addressed syntax warnings by updating regular expression handling to use raw strings, ensuring that backslashes were interpreted correctly and reducing runtime issues. This targeted bug fix improved the robustness and maintainability of the backend code, particularly in how routing logic processes subscription data. Leveraged skills in backend development, API development, and regular expressions to align the codebase with Python 3.12 best practices. The work laid a foundation for future compatibility updates, emphasizing code clarity and reliability in a production backend environment.