The engine's persisted data-model version — the provenance half of
the model stamp, written as modelVersion on every engine-owned
document at its construction and persist choke-points. Conforms-to
semantics: the stamp means "this document conforms to model N now" —
instances are re-stamped on every full persist, so mixed-version fleets
honestly record whichever engine last shaped a doc.
Bump on every declared shape change (additive included). Bumping does NOT
by itself lock out older engines — that is the document's derived
minReaderModel floor. Declare every bump in DATAMODEL.md; the model-surface snapshot test
fails on undeclared drift.
The engine's persisted data-model version — the provenance half of the model stamp, written as
modelVersionon every engine-owned document at its construction and persist choke-points. Conforms-to semantics: the stamp means "this document conforms to model N now" — instances are re-stamped on every full persist, so mixed-version fleets honestly record whichever engine last shaped a doc.Bump on every declared shape change (additive included). Bumping does NOT by itself lock out older engines — that is the document's derived
minReaderModelfloor. Declare every bump inDATAMODEL.md; the model-surface snapshot test fails on undeclared drift.