Donato Santoro worked on optimizing NRF52 firmware for the meshtastic/firmware repository, focusing on reducing binary size and improving build efficiency. He achieved this by removing unused variant files and refining platform configuration, which resulted in measurable memory savings and a more maintainable build process. Donato updated variant configurations for NRF52840 and Rak4631 platforms to exclude unused radios, providing additional memory headroom for future features. His work involved C++ and embedded systems skills, with careful attention to build stability and code cleanliness. The changes streamlined OTA update preparation and were developed collaboratively with the firmware team, demonstrating solid firmware development practices.