architecture-deepening

# Architecture Deepening Find shallow modules and propose deepening opportunities. Not a code review -- does not find bugs or style violations. Finds modules where the interface is too close to the implementation, where users must understand internals to use the API, and where small interface changes would absorb disproportionate complexity. **When to use**: After codebase onboarding or review when improvement was requested, before a cross-module feature, after a fix exposes a missing test seam, or when callers repeatedly need source knowledge or multi-module coordination. **Differs from full-repo-review**: Full-repo-review finds defects. This skill finds structural improvement opportunities. Pair well: run full-repo-review first to fix defects, then architecture-deepening to raise the bar. --- ## Deep References Load on demand when working in the named phase. | Phase | Reference | Content | |-------|-----------|---------| | Phase 1 | `references/maintenance-lifecycle.md` | Entry rules, recent-change scope, decision memory, candidate schema, typed handoff | | Phase 1 | `references/vocabulary.md` | Shared vocabulary: module, depth, seam, leverage, locality, deletion test | | Phase 2 | `references/interface-design.md` | Patterns for exploring alternative interfaces, deletion test | | Phase 2-3 | `references/deepening-strategies.md` | Dependency categorization, safe deepening, testing strategies | ## Instructions Run phases in order until a terminal gate. Survey and des...