Afonso Oliveira developed robust RISC-V interrupt handling and register management features across Zephyr4Microchip/zephyr and riscv-software-src/riscv-unified-db. He integrated RISC-V APLIC support, delivering a core driver with MSI delivery mode, public API exposure, and device-tree bindings to enable scalable interrupt routing. To improve reliability, he refactored indirect CSR access with atomic locking and modularized helpers to prevent circular dependencies. In riscv-unified-db, he introduced memory-mapped register support using physical addresses and unified field management with a shared module, enhancing maintainability. His work leveraged C programming, device driver development, and embedded systems expertise, demonstrating depth in software architecture and backend integration.