DDD Rules

Status: Canonical
Last updated: 2026-07-05

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Layer model

Every product module follows:

Domain/          → entities, value objects, domain services, events
Application/     → actions, services, DTOs, queries
Infrastructure/  → persistence, external APIs
Http/            → controllers, requests (thin)
Providers/       → DI registration
Database/        → migrations, seeders, factories
Tests/           → unit + feature per module

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Rules

Rule	Detail
D-01	Domain has no framework imports except allowed primitives
D-02	Application orchestrates; Domain decides business invariants
D-03	Infrastructure implements repository interfaces defined in Domain or Application
D-04	No cross-module Infrastructure imports
D-05	Writes go through Actions or Application Services
D-06	Reads may use Queries; return DTOs at boundaries

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Bounded context map

See product-specific module index: MODULES/README.md.

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Related

• cqrs-rules.md
• dto-rules.md
• Skill: DDD (materialized in consumer .cursor/skills/ddd/)

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