Phase 4 lane #2 (long_context_cost) measured vault.recall latency
as a function of vault size N. The pre-vectorisation curve was
median 875 ms at N=1k, ~9 s at N=10k — unfit for runtime use.
ADR-0019 Stage 1 replaces the per-element Python dispatch loop in
algebra/backend.py::vault_recall with a vectorised exact scan over
the diagonal Cl(4,1) CGA inner-product metric. Per-versor serial
component reduction order is preserved, so scores are bit-identical
to the scalar cga_inner path. CLAUDE.md exactness is preserved; no
approximate recall is introduced.
Post-vectorisation: 0.217 ms at N=1k, 20.795 ms at N=100k. Slope
0.99 (linear). ~4,000-5,000x speedup at every probed N. Smoke,
algebra, and runtime suites all green.
Stages 2 (norm-bucketed exact pre-filter) and 3 (layered store
with deterministic promotion) are documented in ADR-0019 but
deferred — Stage 1 has dissolved the bottleneck at the scales
relevant to current curriculum work.
Key issues fixed:
- `CORE_BACKEND=numpy` was ignored, so tests mixed Python CGA embedding with Rust metric behavior.
- Dense construction seeds were being rejected by strict `unitize_versor()`, while sparse dirty inputs still needed to fail closed.
- Holonomy needed a construction-boundary path for raw/dense vocab fixtures and rare null final accumulators.
- Proposition storage polluted vault recall by storing the live field instead of the proposition’s subject versor.
- Dialogue qualitative frames rendered the same surface as assertive copular frames.
- Repeated session prompts could collapse into the same deterministic response path.
- Two proof fixtures were stale: one hand-built a non-null “null” vector, and one alignment proof omitted the English “with” anchor used by the resonance proof.
Verification:
`CORE_BACKEND=numpy CORE_STRICT_MLX_ON_APPLE=0 uv run core test -- -q`
Result: `277 passed in 59.52s`