bc-carver

BC Carver

Decide the decomposition, don't perform it. Carving and executing are different acts: the carver produces a written, reviewable cut of the system into business components — the diff a human argues about before the first class moves. Candidates, not verdicts.

Inputs

• migration/GLOSSARY.md — canonical terms and ## Decisions: ground truth, never contradicted.
• migration/CONCEPTS.md — co-occurrence graph and evidence pointers.

No mining, no new concepts. Vocabulary missing here is an extractor defect — stop and re-run /concept-extractor, don't improvise.

Carving Heuristics

• BCs are the dense clusters in the co-occurrence graph; cut along sparse edges.
• Homonym splits settled by the clarifier are the strongest boundary signals — a word that means two things marks two components.
• Name each BC with one canonical glossary term as a single lowercase token (contracts, pricing) — this is the future sbce BC name.
• Give each BC a one-line responsibility phrased in glossary language. If the line needs "and", reconsider the cut.
• Inter-BC references are directed (uses); cycles between candidates are a carving error, not a documentation fact.

CARVING.md Format

Write migration/CARVING.md — regenerable, diffable:

# Carving: <system name>

## Components
### <bc-name>
- **Responsibility:** <one line, glossary language>
- **Concepts:** <canonical terms>
- **Uses:** <bc-name>, ...

## Diff
| Current | Target BC | Layer |
|---|---|---|
| com.legacy.contractmgmt | contracts | — |
| com.legacy.common.ContractValidator | contracts | control |

## Unmapped
<technical noise, dead-code candidates, shared utilities — with reasons>

## Open Questions
### Q<n> — <one-line question>
<evidence; candidate assignments>

• Diff granularity: package-level rows by default; class-level rows only where a package splits across BCs — that is where the information matters, and full class listings on large systems are enormous and instantly stale.
• Layer (boundary | control | entity) only where the evidence supports it; leave — otherwise.
• Unmapped is mandatory — silent omission reads as "covered".
• Open Questions continue the shared Q-id space from CONCEPTS.md: never reuse or renumber ids, continue counting. Ambiguous assignments ("Tariff → contracts or pricing?") are questions, not guesses — resolve via /concept-clarifier.