Worked on the zephyrproject-rtos/zephyr repository to address a UART transmit race condition affecting OpenThread Spinel communication on CC13xx/CC26xx platforms. Focused on embedded systems and driver development using C, the developer replaced free-space polling in the UART driver with TX Ready interrupt gating. This approach resolved a race between otPlatUartSend completion and write_length initialization, which previously risked data framing errors. The solution was delivered as a well-documented, signed-off commit that clearly outlined both the root cause and the implemented fix, enhancing the reliability of OpenThread Spinel framing for the targeted microcontroller units in Zephyr’s codebase.