Spec spec_041
SPEC-041: Write Coordinator
v3 · draft · Owner: Q
Ingestion writes: (1) vector to LanceDB, (2) metadata to SQLite, (3) edges to graph. If step 1 succeeds and step 2 fails = ghost record. LanceDB is eventually consistent, SQLite is ACID, graph is in-memory.

Definition

Anam #04: "Three databases with incompatible transaction models. No write coordinator. Ghost records on partial failure."

Problem: Ingestion writes: (1) vector to LanceDB, (2) metadata to SQLite, (3) edges to graph. If step 1 succeeds and step 2 fails = ghost record. LanceDB is eventually consistent, SQLite is ACID, graph is in-memory.

Proposed: SQLite journal as source of truth. All writes go to SQLite first. LanceDB and graph are derived stores. Rebuild from SQLite must be a documented, tested procedure. Write sequence: SQLite → LanceDB → graph. On failure at any step: rollback SQLite, flag for retry.

Changelog

v3 2026-04-05 Q Mapped to whitepaper sections

v2 2026-04-05 Q Imported SPEC-041 from model_specifications_v2.html

v1 2026-04-05 Q Created spec: SPEC-041: Write Coordinator