cc-skill-frontend-patterns-v2

---
name: cc-skill-frontend-patterns-v2
description: "Frontend Development Patterns workflow skill. Use this skill when the user needs Frontend development patterns for React, Next.js, state management, performance optimization, and UI best practices and the operator should preserve the upstream workflow, copied support files, and provenance before merging or handing off."
version: "0.0.1"
category: frontend
tags: ["cc-skill-frontend-patterns-v2", "cc-skill-frontend-patterns", "frontend", "development", "patterns", "for", "react", "next"]
complexity: advanced
risk: safe
tools: ["codex-cli", "claude-code", "cursor", "gemini-cli", "opencode"]
source: community
author: "sickn33"
date_added: "2026-04-19"
date_updated: "2026-04-25"
---

# Frontend Development Patterns

## Overview

This public intake copy packages `plugins/antigravity-awesome-skills/skills/cc-skill-frontend-patterns` from `https://github.com/sickn33/antigravity-awesome-skills` into the native Omni Skills editorial shape without hiding its origin.

Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.

This intake keeps the copied upstream files intact and uses the `external_source` block in `metadata.json` plus `ORIGIN.md` as the provenance anchor for review.

# Frontend Development Patterns Modern frontend patterns for React, Next.js, and performant user interfaces.

Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: Component Patterns, Custom Hooks Patterns, State Management Patterns, Performance Optimization, Form Handling Patterns, Error Boundary Pattern.

## When to Use This Skill

Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.

- This skill is applicable to execute the workflow or actions described in the overview.
- Use when the request clearly matches the imported source intent: Frontend development patterns for React, Next.js, state management, performance optimization, and UI best practices.
- Use when the operator should preserve upstream workflow detail instead of rewriting the process from scratch.
- Use when provenance needs to stay visible in the answer, PR, or review packet.
- Use when copied upstream references, examples, or scripts materially improve the answer.
- Use when the workflow should remain reviewable in the public intake repo before the private enhancer takes over.

## Operating Table

| Situation | Start here | Why it matters |
| --- | --- | --- |
| First-time use | `metadata.json` | Confirms repository, branch, commit, and imported path through the `external_source` block before touching the copied workflow |
| Provenance review | `ORIGIN.md` | Gives reviewers a plain-language audit trail for the imported source |
| Workflow execution | `SKILL.md` | Starts with the smallest copied file that materially changes execution |
| Supporting context | `SKILL.md` | Adds the next most relevant copied source file without loading the entire package |
| Handoff decision | `## Related Skills` | Helps the operator switch to a stronger native skill when the task drifts |

## Workflow

This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.

1. Confirm the user goal, the scope of the imported workflow, and whether this skill is still the right router for the task.
2. Read the overview and provenance files before loading any copied upstream support files.
3. Load only the references, examples, prompts, or scripts that materially change the outcome for the current request.
4. Execute the upstream workflow while keeping provenance and source boundaries explicit in the working notes.
5. Validate the result against the upstream expectations and the evidence you can point to in the copied files.
6. Escalate or hand off to a related skill when the work moves out of this imported workflow's center of gravity.
7. Before merge or closure, record what was used, what changed, and what the reviewer still needs to verify.

### Imported Workflow Notes

#### Imported: Component Patterns

### Composition Over Inheritance

```typescript
// ✅ GOOD: Component composition
interface CardProps {
  children: React.ReactNode
  variant?: 'default' | 'outlined'
}

export function Card({ children, variant = 'default' }: CardProps) {
  return <div className={`card card-${variant}`}>{children}</div>
}

export function CardHeader({ children }: { children: React.ReactNode }) {
  return <div className="card-header">{children}</div>
}

export function CardBody({ children }: { children: React.ReactNode }) {
  return <div className="card-body">{children}</div>
}

// Usage
<Card>
  <CardHeader>Title</CardHeader>
  <CardBody>Content</CardBody>
</Card>
```

### Compound Components

```typescript
interface TabsContextValue {
  activeTab: string
  setActiveTab: (tab: string) => void
}

const TabsContext = createContext<TabsContextValue | undefined>(undefined)

export function Tabs({ children, defaultTab }: {
  children: React.ReactNode
  defaultTab: string
}) {
  const [activeTab, setActiveTab] = useState(defaultTab)

  return (
    <TabsContext.Provider value={{ activeTab, setActiveTab }}>
      {children}
    </TabsContext.Provider>
  )
}

export function TabList({ children }: { children: React.ReactNode }) {
  return <div className="tab-list">{children}</div>
}

export function Tab({ id, children }: { id: string, children: React.ReactNode }) {
  const context = useContext(TabsContext)
  if (!context) throw new Error('Tab must be used within Tabs')

  return (
    <button
      className={context.activeTab === id ? 'active' : ''}
      onClick={() => context.setActiveTab(id)}
    >
      {children}
    </button>
  )
}

// Usage
<Tabs defaultTab="overview">
  <TabList>
    <Tab id="overview">Overview</Tab>
    <Tab id="details">Details</Tab>
  </TabList>
</Tabs>
```

### Render Props Pattern

```typescript
interface DataLoaderProps<T> {
  url: string
  children: (data: T | null, loading: boolean, error: Error | null) => React.ReactNode
}

export function DataLoader<T>({ url, children }: DataLoaderProps<T>) {
  const [data, setData] = useState<T | null>(null)
  const [loading, setLoading] = useState(true)
  const [error, setError] = useState<Error | null>(null)

  useEffect(() => {
    fetch(url)
      .then(res => res.json())
      .then(setData)
      .catch(setError)
      .finally(() => setLoading(false))
  }, [url])

  return <>{children(data, loading, error)}</>
}

// Usage
<DataLoader<Market[]> url="/api/markets">
  {(markets, loading, error) => {
    if (loading) return <Spinner />
    if (error) return <Error error={error} />
    return <MarketList markets={markets!} />
  }}
</DataLoader>
```

## Examples

### Example 1: Ask for the upstream workflow directly

```text
Use @cc-skill-frontend-patterns-v2 to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.
```

**Explanation:** This is the safest starting point when the operator needs the imported workflow, but not the entire repository.

### Example 2: Ask for a provenance-grounded review

```text
Review @cc-skill-frontend-patterns-v2 against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.
```

**Explanation:** Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.

### Example 3: Narrow the copied support files before execution

```text
Use @cc-skill-frontend-patterns-v2 for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.
```

**Explanation:** This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.

### Example 4: Build a reviewer packet

```text
Review @cc-skill-frontend-patterns-v2 using the copied upstream files plus provenance, then summarize any gaps before merge.
```

**Explanation:** This is useful when the PR is waiting for human review and you want a repeatable audit packet.



## Best Practices

Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.

- Keep the imported skill grounded in the upstream repository; do not invent steps that the source material cannot support.
- Prefer the smallest useful set of support files so the workflow stays auditable and fast to review.
- Keep provenance, source commit, and imported file paths visible in notes and PR descriptions.
- Point directly at the copied upstream files that justify the workflow instead of relying on generic review boilerplate.
- Treat generated examples as scaffolding; adapt them to the concrete task before execution.
- Route to a stronger native skill when architecture, debugging, design, or security concerns become dominant.



## Troubleshooting

### Problem: The operator skipped the imported context and answered too generically

**Symptoms:** The result ignores the upstream workflow in `plugins/antigravity-awesome-skills/skills/cc-skill-frontend-patterns`, fails to mention provenance, or does not use any copied source files at all.
**Solution:** Re-open `metadata.json`, `ORIGIN.md`, and the most relevant copied upstream files. Check the `external_source` block first, then restate the provenance before continuing.

### Problem: The imported workflow feels incomplete during review

**Symptoms:** Reviewers can see the generated `SKILL.md`, but they cannot quickly tell which references, examples, or scripts matter for the current task.
**Solution:** Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.

### Problem: The task drifted into a different specialization

**Symptoms:** The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better.
**Solution:** Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.



## Related Skills

- `@00-andruia-consultant` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@00-andruia-consultant-v2` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@10-andruia-skill-smith` - Use when the work is better handled by that native specialization after this imported skill establishes context.
- `@10-andruia-skill-smith-v2` - Use when the work is better handled by that native specialization after this imported skill establishes context.

## Additional Resources

Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.

| Resource family | What it gives the reviewer | Example path |
| --- | --- | --- |
| `references` | copied reference notes, guides, or background material from upstream | `references/n/a` |
| `examples` | worked examples or reusable prompts copied from upstream | `examples/n/a` |
| `scripts` | upstream helper scripts that change execution or validation | `scripts/n/a` |
| `agents` | routing or delegation notes that are genuinely part of the imported package | `agents/n/a` |
| `assets` | supporting assets or schemas copied from the source package | `assets/n/a` |



### Imported Reference Notes

#### Imported: Custom Hooks Patterns

### State Management Hook

```typescript
export function useToggle(initialValue = false): [boolean, () => void] {
  const [value, setValue] = useState(initialValue)

  const toggle = useCallback(() => {
    setValue(v => !v)
  }, [])

  return [value, toggle]
}

// Usage
const [isOpen, toggleOpen] = useToggle()
```

### Async Data Fetching Hook

```typescript
interface UseQueryOptions<T> {
  onSuccess?: (data: T) => void
  onError?: (error: Error) => void
  enabled?: boolean
}

export function useQuery<T>(
  key: string,
  fetcher: () => Promise<T>,
  options?: UseQueryOptions<T>
) {
  const [data, setData] = useState<T | null>(null)
  const [error, setError] = useState<Error | null>(null)
  const [loading, setLoading] = useState(false)

  const refetch = useCallback(async () => {
    setLoading(true)
    setError(null)

    try {
      const result = await fetcher()
      setData(result)
      options?.onSuccess?.(result)
    } catch (err) {
      const error = err as Error
      setError(error)
      options?.onError?.(error)
    } finally {
      setLoading(false)
    }
  }, [fetcher, options])

  useEffect(() => {
    if (options?.enabled !== false) {
      refetch()
    }
  }, [key, refetch, options?.enabled])

  return { data, error, loading, refetch }
}

// Usage
const { data: markets, loading, error, refetch } = useQuery(
  'markets',
  () => fetch('/api/markets').then(r => r.json()),
  {
    onSuccess: data => console.log('Fetched', data.length, 'markets'),
    onError: err => console.error('Failed:', err)
  }
)
```

### Debounce Hook

```typescript
export function useDebounce<T>(value: T, delay: number): T {
  const [debouncedValue, setDebouncedValue] = useState<T>(value)

  useEffect(() => {
    const handler = setTimeout(() => {
      setDebouncedValue(value)
    }, delay)

    return () => clearTimeout(handler)
  }, [value, delay])

  return debouncedValue
}

// Usage
const [searchQuery, setSearchQuery] = useState('')
const debouncedQuery = useDebounce(searchQuery, 500)

useEffect(() => {
  if (debouncedQuery) {
    performSearch(debouncedQuery)
  }
}, [debouncedQuery])
```

#### Imported: State Management Patterns

### Context + Reducer Pattern

```typescript
interface State {
  markets: Market[]
  selectedMarket: Market | null
  loading: boolean
}

type Action =
  | { type: 'SET_MARKETS'; payload: Market[] }
  | { type: 'SELECT_MARKET'; payload: Market }
  | { type: 'SET_LOADING'; payload: boolean }

function reducer(state: State, action: Action): State {
  switch (action.type) {
    case 'SET_MARKETS':
      return { ...state, markets: action.payload }
    case 'SELECT_MARKET':
      return { ...state, selectedMarket: action.payload }
    case 'SET_LOADING':
      return { ...state, loading: action.payload }
    default:
      return state
  }
}

const MarketContext = createContext<{
  state: State
  dispatch: Dispatch<Action>
} | undefined>(undefined)

export function MarketProvider({ children }: { children: React.ReactNode }) {
  const [state, dispatch] = useReducer(reducer, {
    markets: [],
    selectedMarket: null,
    loading: false
  })

  return (
    <MarketContext.Provider value={{ state, dispatch }}>
      {children}
    </MarketContext.Provider>
  )
}

export function useMarkets() {
  const context = useContext(MarketContext)
  if (!context) throw new Error('useMarkets must be used within MarketProvider')
  return context
}
```

#### Imported: Performance Optimization

### Memoization

```typescript
// ✅ useMemo for expensive computations
const sortedMarkets = useMemo(() => {
  return markets.sort((a, b) => b.volume - a.volume)
}, [markets])

// ✅ useCallback for functions passed to children
const handleSearch = useCallback((query: string) => {
  setSearchQuery(query)
}, [])

// ✅ React.memo for pure components
export const MarketCard = React.memo<MarketCardProps>(({ market }) => {
  return (
    <div className="market-card">
      <h3>{market.name}</h3>
      <p>{market.description}</p>
    </div>
  )
})
```

### Code Splitting & Lazy Loading

```typescript
import { lazy, Suspense } from 'react'

// ✅ Lazy load heavy components
const HeavyChart = lazy(() => import('./HeavyChart'))
const ThreeJsBackground = lazy(() => import('./ThreeJsBackground'))

export function Dashboard() {
  return (
    <div>
      <Suspense fallback={<ChartSkeleton />}>
        <HeavyChart data={data} />
      </Suspense>

      <Suspense fallback={null}>
        <ThreeJsBackground />
      </Suspense>
    </div>
  )
}
```

### Virtualization for Long Lists

```typescript
import { useVirtualizer } from '@tanstack/react-virtual'

export function VirtualMarketList({ markets }: { markets: Market[] }) {
  const parentRef = useRef<HTMLDivElement>(null)

  const virtualizer = useVirtualizer({
    count: markets.length,
    getScrollElement: () => parentRef.current,
    estimateSize: () => 100,  // Estimated row height
    overscan: 5  // Extra items to render
  })

  return (
    <div ref={parentRef} style={{ height: '600px', overflow: 'auto' }}>
      <div
        style={{
          height: `${virtualizer.getTotalSize()}px`,
          position: 'relative'
        }}
      >
        {virtualizer.getVirtualItems().map(virtualRow => (
          <div
            key={virtualRow.index}
            style={{
              position: 'absolute',
              top: 0,
              left: 0,
              width: '100%',
              height: `${virtualRow.size}px`,
              transform: `translateY(${virtualRow.start}px)`
            }}
          >
            <MarketCard market={markets[virtualRow.index]} />
          </div>
        ))}
      </div>
    </div>
  )
}
```

#### Imported: Form Handling Patterns

### Controlled Form with Validation

```typescript
interface FormData {
  name: string
  description: string
  endDate: string
}

interface FormErrors {
  name?: string
  description?: string
  endDate?: string
}

export function CreateMarketForm() {
  const [formData, setFormData] = useState<FormData>({
    name: '',
    description: '',
    endDate: ''
  })

  const [errors, setErrors] = useState<FormErrors>({})

  const validate = (): boolean => {
    const newErrors: FormErrors = {}

    if (!formData.name.trim()) {
      newErrors.name = 'Name is required'
    } else if (formData.name.length > 200) {
      newErrors.name = 'Name must be under 200 characters'
    }

    if (!formData.description.trim()) {
      newErrors.description = 'Description is required'
    }

    if (!formData.endDate) {
      newErrors.endDate = 'End date is required'
    }

    setErrors(newErrors)
    return Object.keys(newErrors).length === 0
  }

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault()

    if (!validate()) return

    try {
      await createMarket(formData)
      // Success handling
    } catch (error) {
      // Error handling
    }
  }

  return (
    <form onSubmit={handleSubmit}>
      <input
        value={formData.name}
        onChange={e => setFormData(prev => ({ ...prev, name: e.target.value }))}
        placeholder="Market name"
      />
      {errors.name && <span className="error">{errors.name}</span>}

      {/* Other fields */}

      <button type="submit">Create Market</button>
    </form>
  )
}
```

#### Imported: Error Boundary Pattern

```typescript
interface ErrorBoundaryState {
  hasError: boolean
  error: Error | null
}

export class ErrorBoundary extends React.Component<
  { children: React.ReactNode },
  ErrorBoundaryState
> {
  state: ErrorBoundaryState = {
    hasError: false,
    error: null
  }

  static getDerivedStateFromError(error: Error): ErrorBoundaryState {
    return { hasError: true, error }
  }

  componentDidCatch(error: Error, errorInfo: React.ErrorInfo) {
    console.error('Error boundary caught:', error, errorInfo)
  }

  render() {
    if (this.state.hasError) {
      return (
        <div className="error-fallback">
          <h2>Something went wrong</h2>
          <p>{this.state.error?.message}</p>
          <button onClick={() => this.setState({ hasError: false })}>
            Try again
          </button>
        </div>
      )
    }

    return this.props.children
  }
}

// Usage
<ErrorBoundary>
  <App />
</ErrorBoundary>
```

#### Imported: Animation Patterns

### Framer Motion Animations

```typescript
import { motion, AnimatePresence } from 'framer-motion'

// ✅ List animations
export function AnimatedMarketList({ markets }: { markets: Market[] }) {
  return (
    <AnimatePresence>
      {markets.map(market => (
        <motion.div
          key={market.id}
          initial={{ opacity: 0, y: 20 }}
          animate={{ opacity: 1, y: 0 }}
          exit={{ opacity: 0, y: -20 }}
          transition={{ duration: 0.3 }}
        >
          <MarketCard market={market} />
        </motion.div>
      ))}
    </AnimatePresence>
  )
}

// ✅ Modal animations
export function Modal({ isOpen, onClose, children }: ModalProps) {
  return (
    <AnimatePresence>
      {isOpen && (
        <>
          <motion.div
            className="modal-overlay"
            initial={{ opacity: 0 }}
            animate={{ opacity: 1 }}
            exit={{ opacity: 0 }}
            onClick={onClose}
          />
          <motion.div
            className="modal-content"
            initial={{ opacity: 0, scale: 0.9, y: 20 }}
            animate={{ opacity: 1, scale: 1, y: 0 }}
            exit={{ opacity: 0, scale: 0.9, y: 20 }}
          >
            {children}
          </motion.div>
        </>
      )}
    </AnimatePresence>
  )
}
```

#### Imported: Accessibility Patterns

### Keyboard Navigation

```typescript
export function Dropdown({ options, onSelect }: DropdownProps) {
  const [isOpen, setIsOpen] = useState(false)
  const [activeIndex, setActiveIndex] = useState(0)

  const handleKeyDown = (e: React.KeyboardEvent) => {
    switch (e.key) {
      case 'ArrowDown':
        e.preventDefault()
        setActiveIndex(i => Math.min(i + 1, options.length - 1))
        break
      case 'ArrowUp':
        e.preventDefault()
        setActiveIndex(i => Math.max(i - 1, 0))
        break
      case 'Enter':
        e.preventDefault()
        onSelect(options[activeIndex])
        setIsOpen(false)
        break
      case 'Escape':
        setIsOpen(false)
        break
    }
  }

  return (
    <div
      role="combobox"
      aria-expanded={isOpen}
      aria-haspopup="listbox"
      onKeyDown={handleKeyDown}
    >
      {/* Dropdown implementation */}
    </div>
  )
}
```

### Focus Management

```typescript
export function Modal({ isOpen, onClose, children }: ModalProps) {
  const modalRef = useRef<HTMLDivElement>(null)
  const previousFocusRef = useRef<HTMLElement | null>(null)

  useEffect(() => {
    if (isOpen) {
      // Save currently focused element
      previousFocusRef.current = document.activeElement as HTMLElement

      // Focus modal
      modalRef.current?.focus()
    } else {
      // Restore focus when closing
      previousFocusRef.current?.focus()
    }
  }, [isOpen])

  return isOpen ? (
    <div
      ref={modalRef}
      role="dialog"
      aria-modal="true"
      tabIndex={-1}
      onKeyDown={e => e.key === 'Escape' && onClose()}
    >
      {children}
    </div>
  ) : null
}
```

**Remember**: Modern frontend patterns enable maintainable, performant user interfaces. Choose patterns that fit your project complexity.

#### Imported: Limitations

- Use this skill only when the task clearly matches the scope described above.
- Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
- Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.