paralleldrive/aidd/aidd-structure

types ← services ← plugins ← components
  ↑         ↑         ↑
  └─────────┴─────────┘ (types only depend on types)

LayerDependency {
  layer: "components" | "plugins" | "services" | "types"
  mayDependOn: String[]
  mustNotDependOn: String[]
}
 
DependencyRules [
  { layer: "components", mayDependOn: ["plugins (Observe<Data>, void actions)", "types"], mustNotDependOn: ["services"] },
  { layer: "plugins", mayDependOn: ["services", "types", "other plugins"], mustNotDependOn: [] },
  { layer: "services", mayDependOn: ["other services", "types"], mustNotDependOn: ["components", "plugins"] },
  { layer: "types", mayDependOn: ["other types"], mustNotDependOn: ["everything else"] }
]
 
Constraints {
  Never: components → services
  Never: services → components or plugins
  Never: types → anything except types
}

components/my-component/
  components/
  plugins/
  types/

fn whenAddingOrMovingCode() {
  Constraints {
    Place code in the correct layer (components, plugins, services, types)
    Check dependencies against the dependency rules
    Fix any violations (e.g. components importing services)
  }
}