Architecture

English Course is built as a hexagon. The domain — entities, the ports it needs from the outside world, and the use cases that act on them — sits at the centre and depends on nothing else. Adapters implement the ports (persistence, email), and the delivery layers — app, components, hooks, lib — drive the use cases.

Each box below is a folder of src/; an arrow means at least one module in the first imports from the second, type-only imports included. The domain layers are outlined in gold. The graph is drawn from the code with dependency-cruiser on every build, so it is never out of date.

Graph of the dependencies between the layers of src. The domain layers — entities, ports, use cases and result — depend only on one another; the delivery layers and the adapters depend on them.

The graph only shows the boundaries. ESLint enforces them: pnpm lint:domain fails when the domain imports anything but zod and neverthrow, and the rules live in openspec/specs/architecture-boundaries.