Andrej Karpathy, who coined "vibe coding" in early 2025, had already moved on to describing its successor as "agentic engineering" by early 2026 - a shift from typing prompts and accepting whatever comes back, to directing an AI system through a disciplined, reviewable engineering process. The distinction matters commercially: a weekend demo built by vibe coding and a production product built through agentic engineering are different deliverables with different failure rates, and conflating them is why so many "AI-built" products stall before launch. Delivery teams built around the disciplined version of this workflow, like SpeedMVPs, are positioned to ship the second outcome, not the first.