Vue Nuxt

Vue 3 & Nuxt 3 — Best Practices & AI-Driven Scaffolding

AI Context & Token Optimization

1. Composition API & <script setup> Only: Do NOT use the Options API. The Composition API is far more token-efficient and predictable for AI code generation.
2. Auto-Imports: Rely entirely on Nuxt's auto-imports. Explicitly importing Vue refs or components wastes tokens and causes syntax hallucinations.
3. TypeScript Mandate: Always use lang="ts". Strongly typed props and Pinia state are required.

Modern Nuxt 3 App Architecture

Scaffold Nuxt 3 applications using these guidelines:

1. Composition API: Always use <script setup lang="ts"> with TypeScript. Banned: Options API.
2. Auto-Imports Leverage: Rely on Nuxt's auto-imported directory structures for composables/, components/, and core Vue APIs (ref, computed, reactive).
3. State Management: Use Pinia via @pinia/nuxt. Define stores using the store-factory function syntax (defineStore('id', () => { ... })).
4. SSR-Safe Data Fetching: Always use useFetch or useAsyncData to ensure data loads on the server and hydrates safely on the client. Banned: standard axios or bare fetch inside components.
5. Form Validation: Use Formkit or VeeValidate + Zod for robust client-side schemas.

Project Structure

project/
├── assets/              # Uncompiled assets (CSS, SCSS)
├── components/          # Auto-imported Vue components
│   └── ui/              # Reusable UI elements (buttons, inputs)
├── composables/         # Auto-imported composition functions (Vue useHooks)
├── layouts/             # Shared page layouts
├── pages/               # File-based routing
├── plugins/             # Vue plugins initialized at startup
├── public/              # Static files served at root
├── server/              # Nitro API routes (Nuxt backend)
│   └── api/
├── stores/              # Pinia state management
└── nuxt.config.ts       # Main Nuxt configuration

Naming Conventions

• Components: PascalCase (e.g., UserProfile.vue). Multi-word names are mandatory.
• Composables: camelCase starting with use (e.g., useAuth.ts).
• Pages/Routes: kebab-case (e.g., user-settings.vue).

Architectural Patterns

• Composition API: Use <script setup lang="ts"> exclusively. Avoid the older Options API (data(), methods).
• Auto-imports: Rely on Nuxt's auto-import feature for components, composables, and Vue APIs (ref, computed). Do not manually import them.
• State Management: Use Pinia for global state. Avoid Vuex.
• Data Fetching: Use useFetch or useAsyncData for SSR-friendly data fetching. Do not use standard fetch or axios directly in components.

Universal DateTime Governance

• API Boundary: All datetimes from the backend are epoch ms or ISO-8601 UTC strings. Normalize to epoch ms in Pinia stores.
• Client Display: Format using Intl.DateTimeFormat with explicit timeZone in a composable (useDateTimeFormatter). Never rely on the browser's locale alone.
• SSR Safety: Use useAsyncData with dayjs.utc() for datetime parsing in server-side code. Never call new Date() in setup() without UTC normalization.
• State: Timestamps in Pinia stores must be epoch ms (number). Convert to localized strings only in template computed properties.

Testing Strategies

• Framework: Vitest + Vue Test Utils.
• Component Testing: Mount components and test DOM output/emitted events.
• E2E Testing: Use Playwright or Cypress.