---

name: vue-fundamentals description: Master Vue.js core concepts - Components, Reactivity, Templates, Directives, Lifecycle sasmp_version: "1.3.0" bonded_agent: 01-vue-fundamentals bond_type: PRIMARY_BOND version: "2.0.0" last_updated: "2025-01"

Vue Fundamentals Skill

Production-grade skill for mastering Vue.js core concepts and building robust component-based applications.

Purpose

Single Responsibility: Teach and validate understanding of Vue.js fundamentals including component architecture, reactivity system, template syntax, directives, and lifecycle hooks.

Parameter Schema

interface VueFundamentalsParams {
  topic: 'components' | 'reactivity' | 'templates' | 'directives' | 'lifecycle' | 'all';
  level: 'beginner' | 'intermediate' | 'advanced';
  context?: {
    current_knowledge?: string[];
    learning_goal?: string;
    time_available?: string;
  };
}

Learning Modules

Module 1: Components (Foundation)

Prerequisites: HTML, CSS, JavaScript basics
Duration: 2-3 hours
Outcome: Build reusable Vue components

Topic	Concept	Exercise
SFC Structure	<template>, <script>, <style>	Create first component
Props	Passing data down	Build Card component
Events	$emit for child→parent	Button with click handler
Slots	Content distribution	Layout component
Registration	Local vs global	Component organization

Module 2: Reactivity (Core)

Prerequisites: Module 1
Duration: 3-4 hours
Outcome: Understand Vue's reactivity system

Topic	Concept	Exercise
ref()	Primitive reactivity	Counter app
reactive()	Object reactivity	Form state
computed()	Derived values	Shopping cart total
watch()	Side effects	API calls on change
watchEffect()	Auto-track	Logging changes

Module 3: Templates (Syntax)

Prerequisites: Module 1
Duration: 2 hours
Outcome: Master template syntax

Topic	Concept	Exercise
Interpolation	{{ }} binding	Display data
v-bind	Attribute binding	Dynamic classes
v-on	Event handling	Form submission
v-model	Two-way binding	Input forms
v-if/v-show	Conditional render	Toggle visibility
v-for	List rendering	Todo list

Module 4: Directives (Built-in & Custom)

Prerequisites: Module 3
Duration: 2 hours
Outcome: Use and create directives

Topic	Concept	Exercise
v-if/else	Conditional	Auth display
v-for + key	Iteration	Data tables
v-model modifiers	.lazy, .trim	Form validation
v-on modifiers	.prevent, .stop	Event control
Custom directives	Reusable DOM logic	v-focus directive

Module 5: Lifecycle (Hooks)

Prerequisites: Modules 1-4
Duration: 2 hours
Outcome: Manage component lifecycle

Hook	Use Case	Example
onMounted	DOM ready	Fetch initial data
onUpdated	After reactivity	Scroll position
onUnmounted	Cleanup	Clear intervals
onErrorCaptured	Error boundary	Graceful degradation

Validation Checkpoints

Beginner Checkpoint

• Create SFC with props and events
• Use ref() for counter
• Apply v-if and v-for
• Handle form with v-model

Intermediate Checkpoint

• Build multi-slot component
• Use computed for derived state
• Implement watch with cleanup
• Create custom directive

Advanced Checkpoint

• Design component composition patterns
• Optimize with shallowRef
• Implement error boundaries
• Build async components

Retry Logic

const skillConfig = {
  maxAttempts: 3,
  backoffMs: [1000, 2000, 4000],
  onFailure: 'provide_hint'
}

Observability

tracking:
  - event: module_started
    data: [module_name, user_level]
  - event: checkpoint_passed
    data: [checkpoint_name, attempts]
  - event: skill_completed
    data: [total_time, score]

Troubleshooting

Common Issues

Issue	Cause	Solution
Component not showing	Not registered	Check import/registration
Props not reactive	Wrong prop type	Use correct type
v-for no key	Missing :key	Add unique key
Infinite loop	watch causing watched change	Guard the update

Debug Steps

1. Check Vue Devtools component tree
2. Verify props are passed correctly
3. Confirm reactive values have .value
4. Check lifecycle hook placement

Unit Test Template

import { describe, it, expect } from 'vitest'
import { mount } from '@vue/test-utils'
import MyComponent from './MyComponent.vue'

describe('MyComponent', () => {
  it('renders props correctly', () => {
    const wrapper = mount(MyComponent, {
      props: { title: 'Test' }
    })
    expect(wrapper.text()).toContain('Test')
  })

  it('emits event on action', async () => {
    const wrapper = mount(MyComponent)
    await wrapper.find('button').trigger('click')
    expect(wrapper.emitted('action')).toBeTruthy()
  })
})

Usage

Skill("vue-fundamentals")

Related Skills

• vue-composition-api - Next level after fundamentals
• vue-typescript - Adding type safety
• vue-testing - Testing fundamentals

Resources

• Vue.js Tutorial
• Vue Mastery
• Vue School