Xeno began leading BIOS security research projects at MITRE in 2011. His team’s first public talks started appearing in 2013, which led to a flurry of presentations on BIOS-level vulnerabilities up through 2014. In 2015 he co-founded LegbaCore. And after presenting a firmware worm that could spread between Macs via Apple’s EFI-based BIOS and Thunderbolt Ethernet adapters, he ended up working for Apple. There he worked on securing all the lesser-known firmwares on Macs and peripherals – everything from 3rd party GPUs to SecureBoot for monitors! He worked on the x86-side of the T2 SecureBoot architecture, and his final project was leading the M1 SecureBoot architecture – being directly responsible for designing a system that could provide iOS-level security, while still allowing customer choice to trust arbitrary non-Apple code such as Linux bootloaders. He left Apple in Dec. 2020 after the M1 Macs shipped, so he could work full time on OpenSecurityTraining2.