Augment Code guide (Paula Hingel) describing how AI agents are restructuring the software development lifecycle (SDLC), stage by stage. Thesis: AI produces **higher throughput in some stages and higher instability risk in others** — a symptom of uneven adoption without redrawing review boundaries. Draws on **DORA 2025**: AI adoption correlates positively with delivery throughput and product performance, but **negatively with stability**. Six stages revisited (Requirements, Design/Architecture, Implementation, Testing/QA, Deployment, Maintenance), three major risks (erosion of the junior pipeline, **circular validation** of AI-generated tests, governance gaps at scale), and three emerging roles (**Intent Engineering**, Agentic DevOps, AI Governance/Assurance). Actionable recommendations: audit one stage before scaling, stress-test governance, make **specification** central, define explicit rollback policies, redesign the junior role around review.