Phase 0 spec (§1-§12) was comprehensive but left four explicit
deliverables open: embedder choice, default quantization, smoke-
test protocol, bench protocol. §13 fills those four with concrete
recommendations + a code structure / test plan / size estimate
that fox can sign off on before Phase 1 code lands.
Recommendations:
- Embedder path 1 (local sentence-transformer bundled as
optional dep); model BAAI/bge-small-en-v1.5 (MIT, 33 MB,
384-dim, unit-normalized, top of MTEB-en/retrieval among
sub-100MB models)
- Default quantization int8 × 384 + flat (6% storage tax,
within the 15% budget per §3.1; binary × 768 reachable via
--vec-quantization=binary)
- Pre-Phase-1 smoke (§13.2): 1k chunks under WAL +
synchronous=NORMAL, kill -9 mid-insert, recovery check;
gate on insert ≥100 chunk/s, p95 query ≤50 ms, zero data
loss
- Bench protocol (§13.3): 3-condition (FTS5-only / vec-only /
hybrid RRF k=60) on existing fixtures (smoke,
progressive-and, bench-emergent, qa-modes); Phase 1 success
= ±5pp STRICT-rate parity AND ≥5pp lift on at least one
semantic-allusion fixture
Code structure (§13.4): 2 new files (embed.py + search/vec.py)
~200 LOC, 4 patches (store.py + query.py + cli.py + Makefile)
~100 LOC, 4 test files ~250 LOC, pyproject.toml [vec] extras
stanza. Single substantial commit when all gates pass.
§13.8 lists the four go/no-go decisions fox needs to make to
unblock Phase 1: embedder path, model name, default quantization,
and approval of the sentence-transformers PyPI dep under [vec]
extras (not pulled by default; only on pip install '.[vec]').
Fallback paths documented for each rejection.
Phase 0 doc remains awaiting go/no-go; §13 doesn't change that
gate, just provides the substance for fox's decision.
russell@unturf.com
96e64b88e6