0015. Maturity levels for every module

Status

Accepted. Date: 2026-11-04.

Context

Full scope is safe only if breadth cannot leak unproven code into production, especially on money paths.

Decision

Every module, kit and adapter carries one label, shown on its docs page and checked by heph doctor. experimental: API may change, not for production; no promotion requirement. beta: API settled, usable in production off the money path; requires passing its contract suite, docs with a runnable example, and use by one ingot. stable: covered by semver and the deprecation policy; requires the coverage gate met, use by two ingots in production, and passing ecosystem CI. New work starts experimental. Money, ledger, idempotency and webhook modules can only be used in a production money path once stable, and heph doctor fails a deploy that breaks this rule.

Consequences

Breadth is allowed without risking production. Everything in Phase 1 ships labelled experimental, so none of it may sit in a production money path yet. Promotion needs real consumers, which creates a deliberate dependency on the ingots using each module. heph doctor must implement the check.