` and animate the wrapper instead.
+
+**Incorrect (animating SVG directly - no hardware acceleration):**
+
+```tsx
+function LoadingSpinner() {
+ return (
+
+ )
+}
+```
+
+**Correct (animating wrapper div - hardware accelerated):**
+
+```tsx
+function LoadingSpinner() {
+ return (
+
+
+
+ )
+}
+```
+
+This applies to all CSS transforms and transitions (`transform`, `opacity`, `translate`, `scale`, `rotate`). The wrapper div allows browsers to use GPU acceleration for smoother animations.
diff --git a/.opencode/skills/frontend-developer/react/rules/rendering-conditional-render.md b/.opencode/skills/frontend-developer/react/rules/rendering-conditional-render.md
new file mode 100644
index 0000000..7e866f5
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rendering-conditional-render.md
@@ -0,0 +1,40 @@
+---
+title: Use Explicit Conditional Rendering
+impact: LOW
+impactDescription: prevents rendering 0 or NaN
+tags: rendering, conditional, jsx, falsy-values
+---
+
+## Use Explicit Conditional Rendering
+
+Use explicit ternary operators (`? :`) instead of `&&` for conditional rendering when the condition can be `0`, `NaN`, or other falsy values that render.
+
+**Incorrect (renders "0" when count is 0):**
+
+```tsx
+function Badge({ count }: { count: number }) {
+ return (
+
+ {count && {count}}
+
+ )
+}
+
+// When count = 0, renders:
0
+// When count = 5, renders:
5
+```
+
+**Correct (renders nothing when count is 0):**
+
+```tsx
+function Badge({ count }: { count: number }) {
+ return (
+
+ {count > 0 ? {count} : null}
+
+ )
+}
+
+// When count = 0, renders:
+// When count = 5, renders:
5
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/rendering-content-visibility.md b/.opencode/skills/frontend-developer/react/rules/rendering-content-visibility.md
new file mode 100644
index 0000000..aa66563
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rendering-content-visibility.md
@@ -0,0 +1,38 @@
+---
+title: CSS content-visibility for Long Lists
+impact: HIGH
+impactDescription: faster initial render
+tags: rendering, css, content-visibility, long-lists
+---
+
+## CSS content-visibility for Long Lists
+
+Apply `content-visibility: auto` to defer off-screen rendering.
+
+**CSS:**
+
+```css
+.message-item {
+ content-visibility: auto;
+ contain-intrinsic-size: 0 80px;
+}
+```
+
+**Example:**
+
+```tsx
+function MessageList({ messages }: { messages: Message[] }) {
+ return (
+
+ {messages.map(msg => (
+
+ ))}
+
+ )
+}
+```
+
+For 1000 messages, browser skips layout/paint for ~990 off-screen items (10× faster initial render).
diff --git a/.opencode/skills/frontend-developer/react/rules/rendering-hoist-jsx.md b/.opencode/skills/frontend-developer/react/rules/rendering-hoist-jsx.md
new file mode 100644
index 0000000..32d2f3f
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rendering-hoist-jsx.md
@@ -0,0 +1,46 @@
+---
+title: Hoist Static JSX Elements
+impact: LOW
+impactDescription: avoids re-creation
+tags: rendering, jsx, static, optimization
+---
+
+## Hoist Static JSX Elements
+
+Extract static JSX outside components to avoid re-creation.
+
+**Incorrect (recreates element every render):**
+
+```tsx
+function LoadingSkeleton() {
+ return
+}
+
+function Container() {
+ return (
+
+ {loading && }
+
+ )
+}
+```
+
+**Correct (reuses same element):**
+
+```tsx
+const loadingSkeleton = (
+
+)
+
+function Container() {
+ return (
+
+ {loading && loadingSkeleton}
+
+ )
+}
+```
+
+This is especially helpful for large and static SVG nodes, which can be expensive to recreate on every render.
+
+**Note:** If your project has [React Compiler](https://react.dev/learn/react-compiler) enabled, the compiler automatically hoists static JSX elements and optimizes component re-renders, making manual hoisting unnecessary.
diff --git a/.opencode/skills/frontend-developer/react/rules/rendering-hydration-no-flicker.md b/.opencode/skills/frontend-developer/react/rules/rendering-hydration-no-flicker.md
new file mode 100644
index 0000000..5cf0e79
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rendering-hydration-no-flicker.md
@@ -0,0 +1,82 @@
+---
+title: Prevent Hydration Mismatch Without Flickering
+impact: MEDIUM
+impactDescription: avoids visual flicker and hydration errors
+tags: rendering, ssr, hydration, localStorage, flicker
+---
+
+## Prevent Hydration Mismatch Without Flickering
+
+When rendering content that depends on client-side storage (localStorage, cookies), avoid both SSR breakage and post-hydration flickering by injecting a synchronous script that updates the DOM before React hydrates.
+
+**Incorrect (breaks SSR):**
+
+```tsx
+function ThemeWrapper({ children }: { children: ReactNode }) {
+ // localStorage is not available on server - throws error
+ const theme = localStorage.getItem('theme') || 'light'
+
+ return (
+
+ {children}
+
+ )
+}
+```
+
+Server-side rendering will fail because `localStorage` is undefined.
+
+**Incorrect (visual flickering):**
+
+```tsx
+function ThemeWrapper({ children }: { children: ReactNode }) {
+ const [theme, setTheme] = useState('light')
+
+ useEffect(() => {
+ // Runs after hydration - causes visible flash
+ const stored = localStorage.getItem('theme')
+ if (stored) {
+ setTheme(stored)
+ }
+ }, [])
+
+ return (
+
+ {children}
+
+ )
+}
+```
+
+Component first renders with default value (`light`), then updates after hydration, causing a visible flash of incorrect content.
+
+**Correct (no flicker, no hydration mismatch):**
+
+```tsx
+function ThemeWrapper({ children }: { children: ReactNode }) {
+ return (
+ <>
+
+ {children}
+
+
+
+ )
+}
+```
+
+The inline script executes synchronously before showing the element, ensuring the DOM already has the correct value. No flickering, no hydration mismatch.
+
+This pattern is especially useful for theme toggles, user preferences, authentication states, and any client-only data that should render immediately without flashing default values.
diff --git a/.opencode/skills/frontend-developer/react/rules/rendering-svg-precision.md b/.opencode/skills/frontend-developer/react/rules/rendering-svg-precision.md
new file mode 100644
index 0000000..6d77128
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rendering-svg-precision.md
@@ -0,0 +1,28 @@
+---
+title: Optimize SVG Precision
+impact: LOW
+impactDescription: reduces file size
+tags: rendering, svg, optimization, svgo
+---
+
+## Optimize SVG Precision
+
+Reduce SVG coordinate precision to decrease file size. The optimal precision depends on the viewBox size, but in general reducing precision should be considered.
+
+**Incorrect (excessive precision):**
+
+```svg
+
+```
+
+**Correct (1 decimal place):**
+
+```svg
+
+```
+
+**Automate with SVGO:**
+
+```bash
+npx svgo --precision=1 --multipass icon.svg
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-defer-reads.md b/.opencode/skills/frontend-developer/react/rules/rerender-defer-reads.md
new file mode 100644
index 0000000..e867c95
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-defer-reads.md
@@ -0,0 +1,39 @@
+---
+title: Defer State Reads to Usage Point
+impact: MEDIUM
+impactDescription: avoids unnecessary subscriptions
+tags: rerender, searchParams, localStorage, optimization
+---
+
+## Defer State Reads to Usage Point
+
+Don't subscribe to dynamic state (searchParams, localStorage) if you only read it inside callbacks.
+
+**Incorrect (subscribes to all searchParams changes):**
+
+```tsx
+function ShareButton({ chatId }: { chatId: string }) {
+ const searchParams = useSearchParams()
+
+ const handleShare = () => {
+ const ref = searchParams.get('ref')
+ shareChat(chatId, { ref })
+ }
+
+ return
+}
+```
+
+**Correct (reads on demand, no subscription):**
+
+```tsx
+function ShareButton({ chatId }: { chatId: string }) {
+ const handleShare = () => {
+ const params = new URLSearchParams(window.location.search)
+ const ref = params.get('ref')
+ shareChat(chatId, { ref })
+ }
+
+ return
+}
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-dependencies.md b/.opencode/skills/frontend-developer/react/rules/rerender-dependencies.md
new file mode 100644
index 0000000..47a4d92
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-dependencies.md
@@ -0,0 +1,45 @@
+---
+title: Narrow Effect Dependencies
+impact: LOW
+impactDescription: minimizes effect re-runs
+tags: rerender, useEffect, dependencies, optimization
+---
+
+## Narrow Effect Dependencies
+
+Specify primitive dependencies instead of objects to minimize effect re-runs.
+
+**Incorrect (re-runs on any user field change):**
+
+```tsx
+useEffect(() => {
+ console.log(user.id)
+}, [user])
+```
+
+**Correct (re-runs only when id changes):**
+
+```tsx
+useEffect(() => {
+ console.log(user.id)
+}, [user.id])
+```
+
+**For derived state, compute outside effect:**
+
+```tsx
+// Incorrect: runs on width=767, 766, 765...
+useEffect(() => {
+ if (width < 768) {
+ enableMobileMode()
+ }
+}, [width])
+
+// Correct: runs only on boolean transition
+const isMobile = width < 768
+useEffect(() => {
+ if (isMobile) {
+ enableMobileMode()
+ }
+}, [isMobile])
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-derived-state.md b/.opencode/skills/frontend-developer/react/rules/rerender-derived-state.md
new file mode 100644
index 0000000..e5c899f
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-derived-state.md
@@ -0,0 +1,29 @@
+---
+title: Subscribe to Derived State
+impact: MEDIUM
+impactDescription: reduces re-render frequency
+tags: rerender, derived-state, media-query, optimization
+---
+
+## Subscribe to Derived State
+
+Subscribe to derived boolean state instead of continuous values to reduce re-render frequency.
+
+**Incorrect (re-renders on every pixel change):**
+
+```tsx
+function Sidebar() {
+ const width = useWindowWidth() // updates continuously
+ const isMobile = width < 768
+ return
+}
+```
+
+**Correct (re-renders only when boolean changes):**
+
+```tsx
+function Sidebar() {
+ const isMobile = useMediaQuery('(max-width: 767px)')
+ return
+}
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-functional-setstate.md b/.opencode/skills/frontend-developer/react/rules/rerender-functional-setstate.md
new file mode 100644
index 0000000..b004ef4
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-functional-setstate.md
@@ -0,0 +1,74 @@
+---
+title: Use Functional setState Updates
+impact: MEDIUM
+impactDescription: prevents stale closures and unnecessary callback recreations
+tags: react, hooks, useState, useCallback, callbacks, closures
+---
+
+## Use Functional setState Updates
+
+When updating state based on the current state value, use the functional update form of setState instead of directly referencing the state variable. This prevents stale closures, eliminates unnecessary dependencies, and creates stable callback references.
+
+**Incorrect (requires state as dependency):**
+
+```tsx
+function TodoList() {
+ const [items, setItems] = useState(initialItems)
+
+ // Callback must depend on items, recreated on every items change
+ const addItems = useCallback((newItems: Item[]) => {
+ setItems([...items, ...newItems])
+ }, [items]) // ❌ items dependency causes recreations
+
+ // Risk of stale closure if dependency is forgotten
+ const removeItem = useCallback((id: string) => {
+ setItems(items.filter(item => item.id !== id))
+ }, []) // ❌ Missing items dependency - will use stale items!
+
+ return
+}
+```
+
+The first callback is recreated every time `items` changes, which can cause child components to re-render unnecessarily. The second callback has a stale closure bug—it will always reference the initial `items` value.
+
+**Correct (stable callbacks, no stale closures):**
+
+```tsx
+function TodoList() {
+ const [items, setItems] = useState(initialItems)
+
+ // Stable callback, never recreated
+ const addItems = useCallback((newItems: Item[]) => {
+ setItems(curr => [...curr, ...newItems])
+ }, []) // ✅ No dependencies needed
+
+ // Always uses latest state, no stale closure risk
+ const removeItem = useCallback((id: string) => {
+ setItems(curr => curr.filter(item => item.id !== id))
+ }, []) // ✅ Safe and stable
+
+ return
+}
+```
+
+**Benefits:**
+
+1. **Stable callback references** - Callbacks don't need to be recreated when state changes
+2. **No stale closures** - Always operates on the latest state value
+3. **Fewer dependencies** - Simplifies dependency arrays and reduces memory leaks
+4. **Prevents bugs** - Eliminates the most common source of React closure bugs
+
+**When to use functional updates:**
+
+- Any setState that depends on the current state value
+- Inside useCallback/useMemo when state is needed
+- Event handlers that reference state
+- Async operations that update state
+
+**When direct updates are fine:**
+
+- Setting state to a static value: `setCount(0)`
+- Setting state from props/arguments only: `setName(newName)`
+- State doesn't depend on previous value
+
+**Note:** If your project has [React Compiler](https://react.dev/learn/react-compiler) enabled, the compiler can automatically optimize some cases, but functional updates are still recommended for correctness and to prevent stale closure bugs.
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-lazy-state-init.md b/.opencode/skills/frontend-developer/react/rules/rerender-lazy-state-init.md
new file mode 100644
index 0000000..4ecb350
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-lazy-state-init.md
@@ -0,0 +1,58 @@
+---
+title: Use Lazy State Initialization
+impact: MEDIUM
+impactDescription: wasted computation on every render
+tags: react, hooks, useState, performance, initialization
+---
+
+## Use Lazy State Initialization
+
+Pass a function to `useState` for expensive initial values. Without the function form, the initializer runs on every render even though the value is only used once.
+
+**Incorrect (runs on every render):**
+
+```tsx
+function FilteredList({ items }: { items: Item[] }) {
+ // buildSearchIndex() runs on EVERY render, even after initialization
+ const [searchIndex, setSearchIndex] = useState(buildSearchIndex(items))
+ const [query, setQuery] = useState('')
+
+ // When query changes, buildSearchIndex runs again unnecessarily
+ return
+}
+
+function UserProfile() {
+ // JSON.parse runs on every render
+ const [settings, setSettings] = useState(
+ JSON.parse(localStorage.getItem('settings') || '{}')
+ )
+
+ return
+}
+```
+
+**Correct (runs only once):**
+
+```tsx
+function FilteredList({ items }: { items: Item[] }) {
+ // buildSearchIndex() runs ONLY on initial render
+ const [searchIndex, setSearchIndex] = useState(() => buildSearchIndex(items))
+ const [query, setQuery] = useState('')
+
+ return
+}
+
+function UserProfile() {
+ // JSON.parse runs only on initial render
+ const [settings, setSettings] = useState(() => {
+ const stored = localStorage.getItem('settings')
+ return stored ? JSON.parse(stored) : {}
+ })
+
+ return
+}
+```
+
+Use lazy initialization when computing initial values from localStorage/sessionStorage, building data structures (indexes, maps), reading from the DOM, or performing heavy transformations.
+
+For simple primitives (`useState(0)`), direct references (`useState(props.value)`), or cheap literals (`useState({})`), the function form is unnecessary.
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-memo.md b/.opencode/skills/frontend-developer/react/rules/rerender-memo.md
new file mode 100644
index 0000000..f8982ab
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-memo.md
@@ -0,0 +1,44 @@
+---
+title: Extract to Memoized Components
+impact: MEDIUM
+impactDescription: enables early returns
+tags: rerender, memo, useMemo, optimization
+---
+
+## Extract to Memoized Components
+
+Extract expensive work into memoized components to enable early returns before computation.
+
+**Incorrect (computes avatar even when loading):**
+
+```tsx
+function Profile({ user, loading }: Props) {
+ const avatar = useMemo(() => {
+ const id = computeAvatarId(user)
+ return
+ }, [user])
+
+ if (loading) return
+ return
{avatar}
+}
+```
+
+**Correct (skips computation when loading):**
+
+```tsx
+const UserAvatar = memo(function UserAvatar({ user }: { user: User }) {
+ const id = useMemo(() => computeAvatarId(user), [user])
+ return
+})
+
+function Profile({ user, loading }: Props) {
+ if (loading) return
+ return (
+
+
+
+ )
+}
+```
+
+**Note:** If your project has [React Compiler](https://react.dev/learn/react-compiler) enabled, manual memoization with `memo()` and `useMemo()` is not necessary. The compiler automatically optimizes re-renders.
diff --git a/.opencode/skills/frontend-developer/react/rules/rerender-transitions.md b/.opencode/skills/frontend-developer/react/rules/rerender-transitions.md
new file mode 100644
index 0000000..d99f43f
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/rerender-transitions.md
@@ -0,0 +1,40 @@
+---
+title: Use Transitions for Non-Urgent Updates
+impact: MEDIUM
+impactDescription: maintains UI responsiveness
+tags: rerender, transitions, startTransition, performance
+---
+
+## Use Transitions for Non-Urgent Updates
+
+Mark frequent, non-urgent state updates as transitions to maintain UI responsiveness.
+
+**Incorrect (blocks UI on every scroll):**
+
+```tsx
+function ScrollTracker() {
+ const [scrollY, setScrollY] = useState(0)
+ useEffect(() => {
+ const handler = () => setScrollY(window.scrollY)
+ window.addEventListener('scroll', handler, { passive: true })
+ return () => window.removeEventListener('scroll', handler)
+ }, [])
+}
+```
+
+**Correct (non-blocking updates):**
+
+```tsx
+import { startTransition } from 'react'
+
+function ScrollTracker() {
+ const [scrollY, setScrollY] = useState(0)
+ useEffect(() => {
+ const handler = () => {
+ startTransition(() => setScrollY(window.scrollY))
+ }
+ window.addEventListener('scroll', handler, { passive: true })
+ return () => window.removeEventListener('scroll', handler)
+ }, [])
+}
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/server-after-nonblocking.md b/.opencode/skills/frontend-developer/react/rules/server-after-nonblocking.md
new file mode 100644
index 0000000..e8f5b26
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/server-after-nonblocking.md
@@ -0,0 +1,73 @@
+---
+title: Use after() for Non-Blocking Operations
+impact: MEDIUM
+impactDescription: faster response times
+tags: server, async, logging, analytics, side-effects
+---
+
+## Use after() for Non-Blocking Operations
+
+Use Next.js's `after()` to schedule work that should execute after a response is sent. This prevents logging, analytics, and other side effects from blocking the response.
+
+**Incorrect (blocks response):**
+
+```tsx
+import { logUserAction } from '@/app/utils'
+
+export async function POST(request: Request) {
+ // Perform mutation
+ await updateDatabase(request)
+
+ // Logging blocks the response
+ const userAgent = request.headers.get('user-agent') || 'unknown'
+ await logUserAction({ userAgent })
+
+ return new Response(JSON.stringify({ status: 'success' }), {
+ status: 200,
+ headers: { 'Content-Type': 'application/json' }
+ })
+}
+```
+
+**Correct (non-blocking):**
+
+```tsx
+import { after } from 'next/server'
+import { headers, cookies } from 'next/headers'
+import { logUserAction } from '@/app/utils'
+
+export async function POST(request: Request) {
+ // Perform mutation
+ await updateDatabase(request)
+
+ // Log after response is sent
+ after(async () => {
+ const userAgent = (await headers()).get('user-agent') || 'unknown'
+ const sessionCookie = (await cookies()).get('session-id')?.value || 'anonymous'
+
+ logUserAction({ sessionCookie, userAgent })
+ })
+
+ return new Response(JSON.stringify({ status: 'success' }), {
+ status: 200,
+ headers: { 'Content-Type': 'application/json' }
+ })
+}
+```
+
+The response is sent immediately while logging happens in the background.
+
+**Common use cases:**
+
+- Analytics tracking
+- Audit logging
+- Sending notifications
+- Cache invalidation
+- Cleanup tasks
+
+**Important notes:**
+
+- `after()` runs even if the response fails or redirects
+- Works in Server Actions, Route Handlers, and Server Components
+
+Reference: [https://nextjs.org/docs/app/api-reference/functions/after](https://nextjs.org/docs/app/api-reference/functions/after)
diff --git a/.opencode/skills/frontend-developer/react/rules/server-cache-lru.md b/.opencode/skills/frontend-developer/react/rules/server-cache-lru.md
new file mode 100644
index 0000000..ef6938a
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/server-cache-lru.md
@@ -0,0 +1,41 @@
+---
+title: Cross-Request LRU Caching
+impact: HIGH
+impactDescription: caches across requests
+tags: server, cache, lru, cross-request
+---
+
+## Cross-Request LRU Caching
+
+`React.cache()` only works within one request. For data shared across sequential requests (user clicks button A then button B), use an LRU cache.
+
+**Implementation:**
+
+```typescript
+import { LRUCache } from 'lru-cache'
+
+const cache = new LRUCache
({
+ max: 1000,
+ ttl: 5 * 60 * 1000 // 5 minutes
+})
+
+export async function getUser(id: string) {
+ const cached = cache.get(id)
+ if (cached) return cached
+
+ const user = await db.user.findUnique({ where: { id } })
+ cache.set(id, user)
+ return user
+}
+
+// Request 1: DB query, result cached
+// Request 2: cache hit, no DB query
+```
+
+Use when sequential user actions hit multiple endpoints needing the same data within seconds.
+
+**With Vercel's [Fluid Compute](https://vercel.com/docs/fluid-compute):** LRU caching is especially effective because multiple concurrent requests can share the same function instance and cache. This means the cache persists across requests without needing external storage like Redis.
+
+**In traditional serverless:** Each invocation runs in isolation, so consider Redis for cross-process caching.
+
+Reference: [https://github.com/isaacs/node-lru-cache](https://github.com/isaacs/node-lru-cache)
diff --git a/.opencode/skills/frontend-developer/react/rules/server-cache-react.md b/.opencode/skills/frontend-developer/react/rules/server-cache-react.md
new file mode 100644
index 0000000..87c9ca3
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/server-cache-react.md
@@ -0,0 +1,76 @@
+---
+title: Per-Request Deduplication with React.cache()
+impact: MEDIUM
+impactDescription: deduplicates within request
+tags: server, cache, react-cache, deduplication
+---
+
+## Per-Request Deduplication with React.cache()
+
+Use `React.cache()` for server-side request deduplication. Authentication and database queries benefit most.
+
+**Usage:**
+
+```typescript
+import { cache } from 'react'
+
+export const getCurrentUser = cache(async () => {
+ const session = await auth()
+ if (!session?.user?.id) return null
+ return await db.user.findUnique({
+ where: { id: session.user.id }
+ })
+})
+```
+
+Within a single request, multiple calls to `getCurrentUser()` execute the query only once.
+
+**Avoid inline objects as arguments:**
+
+`React.cache()` uses shallow equality (`Object.is`) to determine cache hits. Inline objects create new references each call, preventing cache hits.
+
+**Incorrect (always cache miss):**
+
+```typescript
+const getUser = cache(async (params: { uid: number }) => {
+ return await db.user.findUnique({ where: { id: params.uid } })
+})
+
+// Each call creates new object, never hits cache
+getUser({ uid: 1 })
+getUser({ uid: 1 }) // Cache miss, runs query again
+```
+
+**Correct (cache hit):**
+
+```typescript
+const getUser = cache(async (uid: number) => {
+ return await db.user.findUnique({ where: { id: uid } })
+})
+
+// Primitive args use value equality
+getUser(1)
+getUser(1) // Cache hit, returns cached result
+```
+
+If you must pass objects, pass the same reference:
+
+```typescript
+const params = { uid: 1 }
+getUser(params) // Query runs
+getUser(params) // Cache hit (same reference)
+```
+
+**Next.js-Specific Note:**
+
+In Next.js, the `fetch` API is automatically extended with request memoization. Requests with the same URL and options are automatically deduplicated within a single request, so you don't need `React.cache()` for `fetch` calls. However, `React.cache()` is still essential for other async tasks:
+
+- Database queries (Prisma, Drizzle, etc.)
+- Heavy computations
+- Authentication checks
+- File system operations
+- Any non-fetch async work
+
+Use `React.cache()` to deduplicate these operations across your component tree.
+
+Reference: [React.cache documentation](https://react.dev/reference/react/cache)
diff --git a/.opencode/skills/frontend-developer/react/rules/server-parallel-fetching.md b/.opencode/skills/frontend-developer/react/rules/server-parallel-fetching.md
new file mode 100644
index 0000000..1affc83
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/server-parallel-fetching.md
@@ -0,0 +1,83 @@
+---
+title: Parallel Data Fetching with Component Composition
+impact: CRITICAL
+impactDescription: eliminates server-side waterfalls
+tags: server, rsc, parallel-fetching, composition
+---
+
+## Parallel Data Fetching with Component Composition
+
+React Server Components execute sequentially within a tree. Restructure with composition to parallelize data fetching.
+
+**Incorrect (Sidebar waits for Page's fetch to complete):**
+
+```tsx
+export default async function Page() {
+ const header = await fetchHeader()
+ return (
+
+ )
+}
+
+async function Sidebar() {
+ const items = await fetchSidebarItems()
+ return
+}
+```
+
+**Correct (both fetch simultaneously):**
+
+```tsx
+async function Header() {
+ const data = await fetchHeader()
+ return {data}
+}
+
+async function Sidebar() {
+ const items = await fetchSidebarItems()
+ return
+}
+
+export default function Page() {
+ return (
+
+
+
+
+ )
+}
+```
+
+**Alternative with children prop:**
+
+```tsx
+async function Header() {
+ const data = await fetchHeader()
+ return {data}
+}
+
+async function Sidebar() {
+ const items = await fetchSidebarItems()
+ return
+}
+
+function Layout({ children }: { children: ReactNode }) {
+ return (
+
+
+ {children}
+
+ )
+}
+
+export default function Page() {
+ return (
+
+
+
+ )
+}
+```
diff --git a/.opencode/skills/frontend-developer/react/rules/server-serialization.md b/.opencode/skills/frontend-developer/react/rules/server-serialization.md
new file mode 100644
index 0000000..39c5c41
--- /dev/null
+++ b/.opencode/skills/frontend-developer/react/rules/server-serialization.md
@@ -0,0 +1,38 @@
+---
+title: Minimize Serialization at RSC Boundaries
+impact: HIGH
+impactDescription: reduces data transfer size
+tags: server, rsc, serialization, props
+---
+
+## Minimize Serialization at RSC Boundaries
+
+The React Server/Client boundary serializes all object properties into strings and embeds them in the HTML response and subsequent RSC requests. This serialized data directly impacts page weight and load time, so **size matters a lot**. Only pass fields that the client actually uses.
+
+**Incorrect (serializes all 50 fields):**
+
+```tsx
+async function Page() {
+ const user = await fetchUser() // 50 fields
+ return
+}
+
+'use client'
+function Profile({ user }: { user: User }) {
+ return {user.name}
// uses 1 field
+}
+```
+
+**Correct (serializes only 1 field):**
+
+```tsx
+async function Page() {
+ const user = await fetchUser()
+ return
+}
+
+'use client'
+function Profile({ name }: { name: string }) {
+ return {name}
+}
+```
diff --git a/.opencode/skills/frontend-developer/references/angular.md b/.opencode/skills/frontend-developer/references/angular.md
new file mode 100644
index 0000000..8a1b948
--- /dev/null
+++ b/.opencode/skills/frontend-developer/references/angular.md
@@ -0,0 +1,52 @@
+# Modern Angular Architecture
+
+**Status**: Definitive Guide
+**Stack**: Angular 17+
+
+## 🏗 Architecture: Standalone & Zone-less
+
+### 1. Standalone Components
+
+- **Ban**: `NgModule` (unless for legacy libs).
+- **Enforce**: `standalone: true` in all components, directives, and pipes.
+- **Why**: Tree-shaking, easier testing, simplified learning curve.
+
+### 2. Signals (State Management)
+
+- **Signals over Observables**: Use Signals for synchronous state. Use RxJS ONLY for complex asynchronous event streams (debounce, switchMap).
+- **Ban**: `Zone.js` (eventually). Prepare for zoneless by using `ChangeDetectionStrategy.OnPush` everywhere.
+
+```typescript
+// ✅ GOOD: Signal
+@Component({ ... changeDetection: ChangeDetectionStrategy.OnPush })
+export class Counter {
+ count = signal(0);
+ double = computed(() => this.count() * 2);
+
+ increment() {
+ this.count.update(c => c + 1);
+ }
+}
+```
+
+### 3. Control Flow Syntax
+
+- **Use**: `@if`, `@for`, `@switch`.
+- **Ban**: `*ngIf`, `*ngFor` (legacy structural directives).
+
+## ⚡ Performance Patterns
+
+### 1. Deferrable Views
+
+- Use `@defer` to lazy load components without routing.
+- Criteria: `@defer (on viewport)` for below-the-fold content.
+
+### 2. Hydration
+
+- Enable Client Hydration in `app.config.ts`.
+- Avoid direct DOM manipulation which breaks hydration.
+
+## 🧪 Testing
+
+- **Harnesses**: Use Component Harnesses for robust tests.
+- **Signals**: Test signals by verifying computed outputs.
diff --git a/.opencode/skills/frontend-developer/references/core-performance.md b/.opencode/skills/frontend-developer/references/core-performance.md
new file mode 100644
index 0000000..bc3a87c
--- /dev/null
+++ b/.opencode/skills/frontend-developer/references/core-performance.md
@@ -0,0 +1,68 @@
+# Core Performance & Accessibility Standards
+
+**Status**: Mandaory
+**Applies To**: ALL Frameworks (React, Vue, Angular, Svelte, etc.)
+
+## 🚀 Performance: The "Zero-Overhead" Standard
+
+### 1. Core Web Vitals (The Holy Trinity)
+
+You must optimize for these metrics _before_ writing business logic.
+
+- **LCP (Largest Contentful Paint)**: < 2.5s
+ - **Strategy**: The LCP element (usually Hero Image or H1) must be in the initial HTML.
+ - **Ban**: Never lazy-load the LCP image. Never use client-side rendering for the LCP element.
+ - **Code**: `![]()
`
+
+- **INP (Interaction to Next Paint)**: < 200ms
+ - **Strategy**: Break up long tasks.
+ - **Ban**: `useEffect` or watchers that run heavy computation on input. Yield to main thread (`scheduler.yield()` or `setTimeout(..., 0)`).
+
+- **CLS (Cumulative Layout Shift)**: < 0.1
+ - **Strategy**: Rigidly defined dimensions for all media and containers.
+ - **Ban**: Images without `width/height`. Ad containers without `min-height`.
+
+### 2. Bundle Analysis
+
+- **Budget**: Initial JS < 50KB (gzip).
+- **Tree-Shaking**: Import specific functions, not whole libraries.
+ - ✅ `import { map } from 'lodash-es'`
+ - ❌ `import _ from 'lodash'`
+- **Splitting**: Route-level splitting is mandatory. Component-level splitting for heavy interactions (modals, charts).
+
+### 3. Image Optimization
+
+- **Formats**: AVIF > WebP > JPG/PNG.
+- **Responsive**: Use `srcset` and `sizes`.
+- **Lazy**: `loading="lazy"` for everything below the fold.
+
+---
+
+## ♿ Accessibility: The "Keyboard First" Standard
+
+**Rule**: If you can't use it with `Tab` + `Enter`/`Space`, it is broken.
+
+### 1. Semantic HTML
+
+- **Buttons**: Use `