Software Systems Architecture is decisive. Systems succeed or fail by it. This Graduate Certificate delivers an intensive, in-depth study of architecture and design best practices from both software and systems engineering perspectives, while teaching you to harness AI throughout the lifecycle: using AI assistants to explore trade-offs, generate and review designs, prototype and test, and maintain rigorous, living documentation (ADRs, C4 models, interface contracts, and doc-as-code workflows) that keeps teams aligned and systems reliable.