Appendix F — Configuring MAGE Across the Product Lifecycle

Much of this book explains MAGE through software realization and evolution. A software product, however, is shaped across a broader lifecycle. Product staff discover what should be built; engineers realize and evolve it; operators run the resulting system and investigate its failures; assurance and compliance work establishes claims about its quality and obligations. These activities ask different engineering questions and therefore call for different configurations of MAGE.

The same modeling principle applies across that lifecycle. A product hypothesis, structured ticket, state machine, operational topology, runbook, incident timeline, or assurance case can each preserve information needed to answer an engineering question. Their purposes, lifetimes, correspondence claims, authority, and uses differ. The surfaces differ in what they need from MAGE. Discovery may preserve uncertainty; Engineering may need explicit system models and strong Alignment; Operations may turn recurring judgment into procedure; Assurance may require evidence connecting models to realization. There is no canonical portfolio of MAGE models or fixed boundary between reasoning and deterministic machinery.

Nor does MAGE require product-wide adoption. Models and mechanisms have construction and carrying costs, and their returns vary by engineering surface and obligation. An organization might begin with ticket-driven change, architecture, operations, or one consequential compliance obligation while leaving the rest of its practice largely unchanged. This appendix examines five recurring surfaces—Product Discovery, Engineering & Realization, Product Management & Maintenance, Operations & Incidents, and Assurance & Compliance—and then considers how useful local investments can connect across the lifecycle. Organizations divide this work differently, and information flows repeatedly among the surfaces. The relevant question is not whether an organization has “adopted MAGE,” but where durable representation and authority repay their cost.