Series: Building EDIFlow - A Clean Architecture Journey in TypeScript (Part 4/6)

Reading Time: ~12 minutes

Recap — Where We Left Off

In Part 3 , we built the Application Layer — Use Cases, Output Ports (interfaces), DTOs, and the UseCaseFactory. Everything depends on abstractions, nothing on implementations.

Now it's time for the Infrastructure Layer — where theory meets reality. This is where IMessageParser becomes EdifactMessageParser , where IMessageStructureRepository becomes FileBasedMessageStructureRepository , and where 126–319 JSON message definitions get loaded at runtime.

┌───────────────────────────────────────────┐ │ 🔥 INFRASTRUCTURE LAYER │ ← You are here │ Parsers · Builders · Repositories │ │ │ │ ┌─────────────────────────────────────┐ │ │ │ Application (Use Cases, Ports) │ │ │ │ ┌───────────────────────────────┐ │ │ │ │ │ Domain (Entities) │ │ │ │ │ └───────────────────────────────┘ │ │ │ └─────────────────────────────────────┘ │ └───────────────────────────────────────────┘

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