During December 2024, Aomader focused on security hardening within the DuendeSoftware/products repository, specifically addressing the OAuth authentication flow. He implemented a targeted fix in C# to update the redirect URI fragment behavior, replacing the deprecated '#_=_' with a safer '#_' fragment when handling error scenarios without an existing fragment. This backend development effort aligned the codebase with current OAuth 2 security recommendations, reducing the risk of token leakage and improving compliance. By concentrating on OAuth and security best practices, Aomader enhanced the reliability and maintainability of the authentication process, ensuring better interoperability with modern OAuth clients and future standards.