The AI landscape changes fast enough that most advice about it goes stale in months. Tutorials age. Frameworks shift. Models get replaced. What does not change is the underlying logic of how good systems are built. Axiom is a practitioner's guide to building software with AI, grounded in first principles instead of tools. Across 12 principles and 6 parts, it gives engineers a stable way to reason about the hardest problems in AI-driven development: how to design for probabilistic output, how to scope autonomous systems safely, how to evaluate what you cannot unit test, and how to build for a technology stack that will not stop changing underneath you. This is not a book about any particular model or framework. It is a book about thinking clearly in a field that rewards it. Tony Adesanwo is a Director of Software Engineering at Match Group, where he brings over 20 years of hands-on experience building and leading software teams. A practitioner as much as a leader, he writes and speaks on engineering leadership, software quality, and the first principles behind AI-driven development.