v1.5.0 — Auto-config verification layer

Highlights

Auto-config verification layer — new preflight + postflight modules give dedupe_df(df) with no args a runtime-safe warranty. Fixes the DBLP-ACM-style crash where auto-config emitted matchkeys referencing __title_key__ without enabling config.domain. Also addresses silent model downloads, useless exact matchkeys on unique IDs, and over-confident weighting of fuzzy fields.

What's new

Preflight — 6 checks before auto-config returns

1. Column resolution — verifies every matchkey / blocking reference resolves; auto-repairs config.domain for domain-extracted column refs.
2. Cardinality bounds — drops exact matchkeys on columns with cardinality ≥ 0.99 (always unique) or < 0.01 (always same).
3. Block-size sanity — warns when block-size distribution is pathological (P99 > 5000 or median < 2).
4. Remote-asset demotion — embedding / record_embedding / cross-encoder rerank are demoted unless allow_remote_assets=True. Offline CI is now safe by default.
5. Low-confidence weight cap — fields with profile confidence < 0.5 can't exceed weight 0.5.

Emits ConfigValidationError on unrepairable issues. PreflightReport attached to the returned config.

Postflight — 4 signals after scoring, before clustering

• Score histogram + bimodality detection → optional threshold nudge.
• Blocking recall estimate (gated, currently deferred).
• Preliminary cluster sizes with bottleneck-pair diagnostics.
• Threshold-band overlap → advisory to try --llm-auto on ambiguous data.

PostflightReport attached to DedupeResult / MatchResult. Stable signals schema enforced by PostflightSignals TypedDict.

New kwargs

• auto_configure_df(..., strict=False) — suppresses postflight adjustments for deterministic parity runs.
• auto_configure_df(..., allow_remote_assets=False) — opt-in to embedding / rerank (default off).

Classifier smarts

• Cardinality ≥ 0.95 → identifier, not phone / zip / numeric.
• New year col_type routed to blocking, not scoring.
• New multi_name col_type for comma/semicolon-delimited author-style fields.
• Low-confidence fields cap at weight 0.3 in weighted matchkeys.

Breaking changes

1. ConfigValidationError — auto_configure_df may now raise on unrepairable issues. dedupe_df / match_df zero-config paths let it propagate. Catch and inspect err.report.findings if you want a partial config.
2. Remote-asset scorers demoted by default. Pass allow_remote_assets=True to keep embedding / record_embedding / rerank=True in auto-generated configs.
3. match_df gained a zero-config code path it didn't have before (required for postflight on the match pipeline).

Examples

• examples/verification_inspection.py — end-to-end walkthrough of preflight findings and postflight signals.
• examples/strict_mode_parity.py — deterministic parity runs with strict=True.

Verification

• 1394 tests pass in the default suite.
• 4 integration tests (marked @pytest.mark.benchmark) pass: DBLP-ACM regression, NCVR no-useless-matchkeys, Abt-Buy offline, frame-shape pin.
• --check-floors gate: DBLP-ACM F1 0.97 ≥ 0.70, Abt-Buy no-LLM 0.44 ≥ 0.42, NCVR synth 1.00 ≥ 0.98.

Install

```bash
pip install --upgrade goldenmatch
```

Thanks

Review loop caught 13 spec + 6 plan + 11 implementation issues pre-merge. Post-merge review added 6 critical fixes + types/docs/tests polish. Full details in PRs #44 and #45.