decomposelisted

# X2 Decompose (D-000) The one place where the model's whole-solution-space view beats the human's slice-by-slice view, and the decisions a slice cannot cheaply reverse. Everything else stays reversible and waits. ## The five-lens session Decompose the story set under five imposed lenses, one pass each, no code: data flow, failure domain, change frequency, team boundary, trust boundary. Look at what disagrees between the five decompositions; the disagreements are where the real shape decision lives. Choose a shape. Record the choice and the four rejected shapes with reasons as `D-000-decomposition.md` in `docs/decisions/`. D-000 also records: - The story set from gate 1. D-000 is the source of truth for it; there is no separate requirements document (the pilot's turn 8b defect was creating one). - The recorded product decisions from ideation. - The persistent schema decisions. Schema is the second stays-ahead asset; approving it is a human turn, and every later migration is an unconditional human turn, every time. - The slice-one definition: the smallest slice that ships real user-visible value end to end. Build scope and design scope are separate rulings: the build is slice-first, the design is whole-product (MET-03); record both. ## The launch and exposure pre-flight Applies when the product will ship to a public audience; rule each concern IN or OUT now, so none of it arrives as ad-hoc directives at the end (record: NS-2, NS-3): - The estate question: does