During March 2026, Vnibio contributed to the nxp-upstream/zephyr repository by implementing 64-bit bitfield support for the WRITE_BIT macro, addressing the need for reliable bitwise operations on modern 64-bit platforms. Using C programming and embedded systems expertise, Vnibio rewrote the macro to handle wider bitfields and developed a dedicated regression test to ensure correctness and portability. The work focused on enhancing macro reliability and reducing the risk of errors in drivers and core components. Through careful unit testing and targeted code changes, Vnibio delivered a robust solution that improved test coverage and supported safer embedded development in Zephyr.