Worked on the LizardByte/Sunshine repository to address a stability issue in the stdin-based PIN pairing flow, focusing on improving user authentication reliability. Using C++ and system programming skills, implemented a guard within the pairing function to ensure it returns immediately after PIN input, thereby preventing unintended continued execution and restoring correct pairing behavior. This targeted bug fix, tracked under issue #4912, reduced production risk and enhanced the robustness of the authentication workflow. The work demonstrated proficiency in debugging input flows, effective use of Git-based version control, and alignment with issue-tracking processes to deliver a more predictable user experience.