SSOT

Enforce exactly one writable authority for each necessary fact, policy, schema,
contract, configuration value, or generation contract. Every other form is a
typed consumer, deterministic projection, disposable cache, or evidence—never a
competing writer or fallback owner.

A canonical calculated default is one owned fact. Declare and validate it once
at the typed owner; consumers omit equal environment variables, settings,
parameters, arguments, fixtures, and projections. Only a current non-derivable
external value or a supported override is explicit.

Consume the current concept set from yagni and read the
authority procedure (skill file). Return one authority map for
implementation, solid, and dry; search-first owns the global route.

Missing ownership, precedence, generator, consumer, or runtime evidence blocks
mutation. File names, docs, tests, caches, and runtime observations do not become
owners by convenience.