Fergus enhanced the systemd/systemd repository by developing a targeted pcrlock feature to improve PCR-based attestation and initrd reliability. Using C programming and embedded systems expertise, Fergus implemented logic to predict Platform Configuration Register values at the start of a specified range, specifically addressing the default 760:940 interval. This approach involved recording predictions immediately before component processing, which reduced edge-case risks and increased the accuracy of PCR state estimation during boot and initrd transitions. The work strengthened the reliability and security of boot-time measurements, contributing to faster and more trustworthy system startup and attestation in system-level environments.