Developed GDB arch15 record and replay support for s390 within the espressif/binutils-gdb repository, focusing on enhancing debugging capabilities for modern z/Architecture targets. Implemented opcode handlers for bit manipulation, arithmetic, and vector operations in C, enabling accurate capture and replay of processor state changes. This work improved debugging fidelity and reproducibility, allowing developers to more efficiently analyze complex workloads and reduce time to root cause for intermittent issues. Demonstrated strong skills in low-level programming, embedded systems, and debugging tools, with a deep understanding of GDB internals and architecture-specific development. No major bugs were addressed during this period.