Dissolve OQ-10's circular "standing offer" framing and record the
engine decision the POC evidence already supported:
- ADR-007 (new): kv tier ships sqlite (default) + postgres (feature
`postgres`, default-off), constructor-selected per node; records the
deployment economics (classical kv+fs+relational downstream stack
collapses to one relational engine + fs), the pg impl contract
(POC #5 B5 posture deltas), the CI sweep-safety gate under
--all-features, redb ruled out (POC #6), and posture defaults as
deferred cost in the ADR-006 pattern
- ADR-003: amended status (engine pin widened by ADR-007); kv entry
notes the widened engine set
- ADR-004: reconciliation note — the "two backends" count is tiers,
not engines
- backends-and-dispatch.md: tier≠engine distinction, pg engine
section, co-tenancy note (same-file consumer writes share sqlite's
single-writer ceiling), substitution-door precedent
- open-questions.md: OQ-10 resolved-by-ADR-007, with the
why-this-is-not-Schrödinger's-code record (a deployment running
alkblobs cannot pre-exist the pg engine — OQ-09 precedent); parked
index narrowed to OQ-07/OQ-08
- overview.md: layer map + dependency posture reflect the `postgres`
feature; README.md: ADR-007 in tables + corollary applications
- phase-0.md / pg+redb findings: promotion + supersession notes
Trigger framing survives only as deployment guidance (which engine a
node chooses — topology, not throughput), not as a gate on the crate's
own work.
Verified: cargo test, clippy --all-targets -D warnings, fmt --check.
Docs-only change (Phase 1 architecture); no implementation yet.
The backends spec read as if the Backend trait were a general storage
abstraction and 'two backends, exactly' banned other storage in a
deployment — so a downstream wanting sqlite manifests appeared forced
into implementing a third backend, the exact weld ADR-004 forbids.
- backends-and-dispatch.md: state plainly that the trait is a CAS-tier
contract (immutable digest-keyed entries, GC-shaped list/delete) and
never a host for manifest/index storage; consumer storage is
beside-the-pool. 'Two, exactly' counts trait impls shipped, not
storage per deployment. kv: tier name vs pinned sqlite engine made
explicit.
- ADR-004: add the explicit corollary under the consumer-seams point.
glm-5.3-flash