During January 2025, Matsul focused on stabilizing security context management in the zephyrproject-rtos/trusted-firmware-a repository. He addressed a critical bug by moving PMUv3 enablement into the common context management initialization, ensuring that MDCR_EL3 was correctly configured during context switches across all security worlds. This approach improved the reliability of cross-world transitions and reduced the risk of misconfiguration, directly enhancing platform integrity. Matsul’s work required deep understanding of ARM architecture, embedded systems, and firmware development, and was implemented in C. The solution demonstrated careful attention to low-level system details and contributed to more robust security handling in trusted firmware environments.