Ports and Adapters
An architecture where the domain core defines abstract boundaries (ports) and all external dependencies plug in through concrete implementations (adapters), also known as Hexagonal Architecture.
↑ ContentsDefinition
In Ports and Adapters, the domain core is pure — data in, data out, no I/O. A port is the boundary where certainty ends and uncertainty begins: filesystem, HTTP, database, time. Adapters implement ports with real infrastructure. The domain never imports an adapter; the adapter always imports the domain. This dependency direction is the constraint that matters most — when it holds, the domain is testable without mocks and portable across infrastructure. Enforcement is the hard part: tools like eslint-plugin-boundaries and clj-depend can check it mechanically.
↑ Contents