Vue.js Development Guides

Tasks Checklist

• Followed the core principles
• Followed the defaults unless there is a good reason not to
• Followed the reactivity best practices
• Followed the component best practices
  • Followed the Vue SFC best practices
  • Kept components focused
    • Split large components into smaller ones when needed
    • Moved state/side effects into composables if applicable
  • Followed data flow best practices

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Core Principles

• Keep state predictable: one source of truth, derive everything else.
• Make data flow explicit: Props down, Events up for most cases.
• Favor small, focused components: easier to test, reuse, and maintain.
• Avoid unnecessary re-renders: use computed properties and watchers wisely.
• Readability counts: write clear, self-documenting code.

Defaults (unless the user says otherwise)

• Prefer the Composition API over the Options API.

Reactivity

IMPORTANT: You MUST follow the references/reactivity-guide.md for reactive state management when creating, updating a component or a composable.

Components

IMPORTANT: You MUST follow the references/sfc-guide.md for best practices when working with Vue SFCs.

• Prefer Vue Single-File Components (SFC) using <script setup lang="ts"> (TypeScript) by default.
• In Vue SFCs, keep sections in this order: <script> → <template> → <style>.

Keep components focused

Split a component when it has more than one clear responsibility (e.g. data orchestration + UI, or multiple independent UI sections).

• Prefer smaller components + composables over one “mega component”
• Move UI sections into child components (props in, events out).
• Move state/side effects into composables (useXxx()).

NOTE: This rule also applies to the entry component (e.g. App.vue) in a Vue / Nuxt project by default.

Data Flow

IMPORTANT: You MUST follow the references/data-flow-guide.md for passing and receiving data between components using:

• Props
• Emits
• v-model
• provide/inject

For sharing data across the app, please follow the references/state-management-guide.md and consider using a Store for state management solution.