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.…