# System Architecture

The package preserves seven layers: System Registry, stable graph, append-preserving candidate ledger, expressions, Realm bindings, Sentinel handoffs, and evolution/lineage. Cards, tiles, games, readings, and this manual are expressions over the graph.

## Core traversal

- [Loan Origination System](../nodes/processes/loan-origination-system.md) — Loan Origination System turns borrower intent into a documented, priced loan file
- [Roof](../nodes/technology/roof.md) — Roof keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Foundation System](../nodes/technology/foundation-system.md) — Foundation System keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Plumbing](../nodes/technology/plumbing.md) — Plumbing keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Electrical System](../nodes/technology/electrical-system.md) — Electrical System keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [HVAC](../nodes/technology/hvac.md) — HVAC keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Elevator](../nodes/technology/elevator.md) — Elevator keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Fire Protection](../nodes/technology/fire-protection.md) — Fire Protection keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Building Envelope — System](../nodes/technology/building-envelope-system.md) — Building Envelope — System keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Utility Service](../nodes/technology/utility-service.md) — Utility Service keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Preventive Maintenance](../nodes/technology/preventive-maintenance.md) — Preventive Maintenance keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Deferred Maintenance](../nodes/technology/deferred-maintenance.md) — Deferred Maintenance keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Capital Expenditure](../nodes/technology/capital-expenditure.md) — Capital Expenditure keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Replacement Reserve](../nodes/technology/replacement-reserve.md) — Replacement Reserve keeps the physical vessel safe, useful, comfortable, and capable of renewal
- [Automated Underwriting System](../nodes/technology/automated-underwriting-system.md) — Automated Underwriting System turns documents, observations, decisions, and physical assets into computational workflows
- [English Freehold](../nodes/rights/english-freehold.md) — English Freehold demonstrates that ownership and mortgage conventions vary by jurisdiction and history
- [English Leasehold](../nodes/rights/english-leasehold.md) — English Leasehold demonstrates that ownership and mortgage conventions vary by jurisdiction and history
- [Scottish Feudal Abolition](../nodes/rights/scottish-feudal-abolition.md) — Scottish Feudal Abolition demonstrates that ownership and mortgage conventions vary by jurisdiction and history

## How to read this chapter

Follow claims and cash flows separately. Ask who holds authority, who supplies information, who receives benefit, who carries risk, and what changes when time or scale changes. Keep sourced fact, industry practice, synthesis, interpretation, and symbolic expression distinguishable.

## Mapshifting prompts

1. Change the unit of analysis from property to right, loan, cash flow, role, record, neighborhood, or institution.
2. Change the clock from closing day to thirty years, one market cycle, one building life, or several generations.
3. Change stakeholder and ask which previously invisible cost becomes central.
4. Return to the human map before choosing a move.

## Sentinel handoff

Legal, regulatory, fair-lending, historical, financial, cultural, and jurisdiction-specific annotations remain separate from Engine Output. They inform contextual use without flattening the graph.
