react-application-structure

React Application Structure Skill

Step 1 — Directory Layout (Feature-Based)

Organise by feature, not by file type. Co-locate everything a feature needs:

src/
  app/
    providers/
      QueryProvider.tsx
      RouterProvider.tsx
  features/
    auth/
      components/
        AuthLoginForm.tsx
      hooks/
        useAuth.ts
      state/
        auth.store.ts
      api/
        auth.api.ts
      types/
        auth.types.ts
  components/
    ui/
      Button.tsx
      Modal.tsx
  routes/
    index.tsx
  lib/
    http.ts
    env.ts
  styles/
  main.tsx

Step 2 — Component and Hook Conventions

• Use function components with TypeScript; no class components.
• Keep components thin; move reusable logic to custom hooks.
• Name hooks with the use prefix and keep single responsibility.
• Keep side effects in hooks/components where they are consumed; avoid hidden global effects.
• Use alias imports for cross-directory modules and ESM import/export syntax only.

interface Props {
  userId: string
  readonly?: boolean
}

export function UserCard({ userId, readonly = false }: Props) {
  const { user } = useAuthUser(userId)
  return <section>{readonly ? user.name : <strong>{user.name}</strong>}</section>
}

Step 3 — State Management Boundaries

• Local transient UI state: useState / useReducer.
• Shared server state: TanStack Query (queries + mutations).
• Shared client state across features: Zustand or Redux Toolkit slice per domain.
• Do not duplicate server state into client stores unless offline/derived behaviour requires it.

Step 4 — Routing and Entry Points

• Use a typed router setup (react-router-dom data routers or framework router).
• Keep route definitions in routes/ and route-level loaders/actions with route modules.
• Lazy-load route components where possible.
• Route guards should be centralized helper wrappers, not repeated inline logic.

Step 5 — Data and API Layer

• Keep API clients in features/*/api or shared lib/http.ts.
• Normalize error handling in one place (interceptor or query/mutation wrapper).
• Validate API payloads at boundaries (for example Zod schemas) before wider app use.