Worked on enhancing the reliability of GPIO interrupt handling in the nxp-upstream/zephyr repository, focusing on embedded systems development using C. Addressed a bug where callbacks could be triggered by disabled GPIO interrupts by implementing an interrupt mask register (IMR)-based guard at the ISR level. This approach ensured that callbacks were only executed when the corresponding interrupt was enabled, effectively eliminating spurious triggers and improving determinism in GPIO-driven workflows. The solution demonstrated a strong understanding of interrupt handling and the Zephyr GPIO subsystem, resulting in improved system stability and reduced unintended behavior across disabled interrupts within embedded C environments.