hexagonal-architecture-layers-java

When to Use

Load this skill when:

• Designing a new Java service with clean, testable layers
• Refactoring Spring code to isolate the domain from frameworks
• Supporting multiple adapters (REST + messaging, JPA + Mongo)
• Enforcing dependency direction and clear module boundaries

Critical Patterns

Pattern 1: Domain is pure

Domain has no framework annotations, no persistence concerns, and no I/O.

Pattern 2: Application orchestrates

Application defines use cases and ports, calling domain logic and delegating I/O to ports.

Pattern 3: Infrastructure adapts