Roman Gogolev focused on backend development for the MHSanaei/3x-ui repository, addressing a critical compatibility issue related to integer parsing on 32-bit architectures. He updated the codebase to use int64 for parsing integers, which prevents overflow errors and ensures correct handling of large values across different platforms. This targeted bug fix improved the reliability of the application, particularly in legacy and cross-platform environments. Roman utilized his expertise in Go to implement and validate the change with minimal risk to existing functionality. His work demonstrated a careful approach to platform compatibility and robust backend engineering within a short project timeframe.