feat: auth & admin

.agents/skills/vercel-react-best-practices/README.md

@@ -10,22 +10,25 @@ A structured repository for creating and maintaining React Best Practices optimi
   - `area-description.md` - Individual rule files
 - `src/` - Build scripts and utilities
 - `metadata.json` - Document metadata (version, organization, abstract)
-- __`AGENTS.md`__ - Compiled output (generated)
+- **`AGENTS.md`** - Compiled output (generated)
-- __`test-cases.json`__ - Test cases for LLM evaluation (generated)
+- **`test-cases.json`** - Test cases for LLM evaluation (generated)
 
 ## Getting Started
 
 1. Install dependencies:
+
    ```bash
    pnpm install
    ```
 
 2. Build AGENTS.md from rules:
+
    ```bash
    pnpm build
    ```
 
 3. Validate rule files:
+
    ```bash
    pnpm validate
    ```
@@ -55,7 +58,7 @@ A structured repository for creating and maintaining React Best Practices optimi
 
 Each rule file should follow this structure:
 
-```markdown
+````markdown
 ---
 title: Rule Title Here
 impact: MEDIUM
@@ -72,6 +75,7 @@ Brief explanation of the rule and why it matters.
 ```typescript
 // Bad code example
 ```
+````
 
 **Correct (description of what's right):**
 

.agents/skills/vercel-react-best-practices/SKILL.md

@@ -4,7 +4,7 @@ description: React and Next.js performance optimization guidelines from Vercel E
 license: MIT
 metadata:
   author: vercel
-  version: "1.0.0"
+  version: '1.0.0'
 ---
 
 # Vercel React Best Practices
@@ -14,6 +14,7 @@ Comprehensive performance optimization guide for React and Next.js applications,
 ## When to Apply
 
 Reference these guidelines when:
+
 - Writing new React components or Next.js pages
 - Implementing data fetching (client or server-side)
 - Reviewing code for performance issues
@@ -22,16 +23,16 @@ Reference these guidelines when:
 
 ## Rule Categories by Priority
 
-| Priority | Category | Impact | Prefix |
+| Priority | Category                  | Impact      | Prefix       |
-|----------|----------|--------|--------|
+| -------- | ------------------------- | ----------- | ------------ |
-| 1 | Eliminating Waterfalls | CRITICAL | `async-` |
+| 1        | Eliminating Waterfalls    | CRITICAL    | `async-`     |
-| 2 | Bundle Size Optimization | CRITICAL | `bundle-` |
+| 2        | Bundle Size Optimization  | CRITICAL    | `bundle-`    |
-| 3 | Server-Side Performance | HIGH | `server-` |
+| 3        | Server-Side Performance   | HIGH        | `server-`    |
-| 4 | Client-Side Data Fetching | MEDIUM-HIGH | `client-` |
+| 4        | Client-Side Data Fetching | MEDIUM-HIGH | `client-`    |
-| 5 | Re-render Optimization | MEDIUM | `rerender-` |
+| 5        | Re-render Optimization    | MEDIUM      | `rerender-`  |
-| 6 | Rendering Performance | MEDIUM | `rendering-` |
+| 6        | Rendering Performance     | MEDIUM      | `rendering-` |
-| 7 | JavaScript Performance | LOW-MEDIUM | `js-` |
+| 7        | JavaScript Performance    | LOW-MEDIUM  | `js-`        |
-| 8 | Advanced Patterns | LOW | `advanced-` |
+| 8        | Advanced Patterns         | LOW         | `advanced-`  |
 
 ## Quick Reference
 
@@ -139,6 +140,7 @@ rules/bundle-barrel-imports.md
 ```
 
 Each rule file contains:
+
 - Brief explanation of why it matters
 - Incorrect code example with explanation
 - Correct code example with explanation

.agents/skills/vercel-react-best-practices/rules/_template.md

@@ -15,14 +15,14 @@ Brief explanation of the rule and why it matters. This should be clear and conci
 
 ```typescript
 // Bad code example here
-const bad = example()
+const bad = example();
 ```
 
 **Correct (description of what's right):**
 
 ```typescript
 // Good code example here
-const good = example()
+const good = example();
 ```
 
 Reference: [Link to documentation or resource](https://example.com)

.agents/skills/vercel-react-best-practices/rules/advanced-effect-event-deps.md

@@ -12,21 +12,24 @@ Effect Event functions do not have a stable identity. Their identity intentional
 **Incorrect (Effect Event added as a dependency):**
 
 ```tsx
-import { useEffect, useEffectEvent } from 'react'
+import { useEffect, useEffectEvent } from 'react';
 
-function ChatRoom({ roomId, onConnected }: {
+function ChatRoom({
-  roomId: string
+  roomId,
-  onConnected: () => void
+  onConnected,
+}: {
+  roomId: string;
+  onConnected: () => void;
 }) {
-  const handleConnected = useEffectEvent(onConnected)
+  const handleConnected = useEffectEvent(onConnected);
 
   useEffect(() => {
-    const connection = createConnection(roomId)
+    const connection = createConnection(roomId);
-    connection.on('connected', handleConnected)
+    connection.on('connected', handleConnected);
-    connection.connect()
+    connection.connect();
 
-    return () => connection.disconnect()
+    return () => connection.disconnect();
-  }, [roomId, handleConnected])
+  }, [roomId, handleConnected]);
 }
 ```
 
@@ -35,21 +38,24 @@ Including the Effect Event in dependencies makes the effect re-run every render
 **Correct (depend on reactive values, not the Effect Event):**
 
 ```tsx
-import { useEffect, useEffectEvent } from 'react'
+import { useEffect, useEffectEvent } from 'react';
 
-function ChatRoom({ roomId, onConnected }: {
+function ChatRoom({
-  roomId: string
+  roomId,
-  onConnected: () => void
+  onConnected,
+}: {
+  roomId: string;
+  onConnected: () => void;
 }) {
-  const handleConnected = useEffectEvent(onConnected)
+  const handleConnected = useEffectEvent(onConnected);
 
   useEffect(() => {
-    const connection = createConnection(roomId)
+    const connection = createConnection(roomId);
-    connection.on('connected', handleConnected)
+    connection.on('connected', handleConnected);
-    connection.connect()
+    connection.connect();
 
-    return () => connection.disconnect()
+    return () => connection.disconnect();
-  }, [roomId])
+  }, [roomId]);
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/advanced-event-handler-refs.md

@@ -14,9 +14,9 @@ Store callbacks in refs when used in effects that shouldn't re-subscribe on call
 ```tsx
 function useWindowEvent(event: string, handler: (e) => void) {
   useEffect(() => {
-    window.addEventListener(event, handler)
+    window.addEventListener(event, handler);
-    return () => window.removeEventListener(event, handler)
+    return () => window.removeEventListener(event, handler);
-  }, [event, handler])
+  }, [event, handler]);
 }
 ```
 
@@ -24,31 +24,31 @@ function useWindowEvent(event: string, handler: (e) => void) {
 
 ```tsx
 function useWindowEvent(event: string, handler: (e) => void) {
-  const handlerRef = useRef(handler)
+  const handlerRef = useRef(handler);
   useEffect(() => {
-    handlerRef.current = handler
+    handlerRef.current = handler;
-  }, [handler])
+  }, [handler]);
 
   useEffect(() => {
-    const listener = (e) => handlerRef.current(e)
+    const listener = (e) => handlerRef.current(e);
-    window.addEventListener(event, listener)
+    window.addEventListener(event, listener);
-    return () => window.removeEventListener(event, listener)
+    return () => window.removeEventListener(event, listener);
-  }, [event])
+  }, [event]);
 }
 ```
 
 **Alternative: use `useEffectEvent` if you're on latest React:**
 
 ```tsx
-import { useEffectEvent } from 'react'
+import { useEffectEvent } from 'react';
 
 function useWindowEvent(event: string, handler: (e) => void) {
-  const onEvent = useEffectEvent(handler)
+  const onEvent = useEffectEvent(handler);
 
   useEffect(() => {
-    window.addEventListener(event, onEvent)
+    window.addEventListener(event, onEvent);
-    return () => window.removeEventListener(event, onEvent)
+    return () => window.removeEventListener(event, onEvent);
-  }, [event])
+  }, [event]);
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/advanced-init-once.md

@@ -14,9 +14,9 @@ Do not put app-wide initialization that must run once per app load inside `useEf
 ```tsx
 function Comp() {
   useEffect(() => {
-    loadFromStorage()
+    loadFromStorage();
-    checkAuthToken()
+    checkAuthToken();
-  }, [])
+  }, []);
 
   // ...
 }
@@ -25,15 +25,15 @@ function Comp() {
 **Correct (once per app load):**
 
 ```tsx
-let didInit = false
+let didInit = false;
 
 function Comp() {
   useEffect(() => {
-    if (didInit) return
+    if (didInit) return;
-    didInit = true
+    didInit = true;
-    loadFromStorage()
+    loadFromStorage();
-    checkAuthToken()
+    checkAuthToken();
-  }, [])
+  }, []);
 
   // ...
 }

.agents/skills/vercel-react-best-practices/rules/advanced-use-latest.md

@@ -13,12 +13,12 @@ Access latest values in callbacks without adding them to dependency arrays. Prev
 
 ```tsx
 function SearchInput({ onSearch }: { onSearch: (q: string) => void }) {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
 
   useEffect(() => {
-    const timeout = setTimeout(() => onSearch(query), 300)
+    const timeout = setTimeout(() => onSearch(query), 300);
-    return () => clearTimeout(timeout)
+    return () => clearTimeout(timeout);
-  }, [query, onSearch])
+  }, [query, onSearch]);
 }
 ```
 
@@ -28,12 +28,12 @@ function SearchInput({ onSearch }: { onSearch: (q: string) => void }) {
 import { useEffectEvent } from 'react';
 
 function SearchInput({ onSearch }: { onSearch: (q: string) => void }) {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
-  const onSearchEvent = useEffectEvent(onSearch)
+  const onSearchEvent = useEffectEvent(onSearch);
 
   useEffect(() => {
-    const timeout = setTimeout(() => onSearchEvent(query), 300)
+    const timeout = setTimeout(() => onSearchEvent(query), 300);
-    return () => clearTimeout(timeout)
+    return () => clearTimeout(timeout);
-  }, [query])
+  }, [query]);
 }
 ```

.agents/skills/vercel-react-best-practices/rules/async-api-routes.md

@@ -13,10 +13,10 @@ In API routes and Server Actions, start independent operations immediately, even
 
 ```typescript
 export async function GET(request: Request) {
-  const session = await auth()
+  const session = await auth();
-  const config = await fetchConfig()
+  const config = await fetchConfig();
-  const data = await fetchData(session.user.id)
+  const data = await fetchData(session.user.id);
-  return Response.json({ data, config })
+  return Response.json({ data, config });
 }
 ```
 
@@ -24,14 +24,14 @@ export async function GET(request: Request) {
 
 ```typescript
 export async function GET(request: Request) {
-  const sessionPromise = auth()
+  const sessionPromise = auth();
-  const configPromise = fetchConfig()
+  const configPromise = fetchConfig();
-  const session = await sessionPromise
+  const session = await sessionPromise;
   const [config, data] = await Promise.all([
     configPromise,
-    fetchData(session.user.id)
+    fetchData(session.user.id),
-  ])
+  ]);
-  return Response.json({ data, config })
+  return Response.json({ data, config });
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/async-cheap-condition-before-await.md

@@ -14,7 +14,7 @@ This is a specialization of [Defer Await Until Needed](./async-defer-await.md) f
 **Incorrect:**
 
 ```typescript
-const someFlag = await getFlag()
+const someFlag = await getFlag();
 
 if (someFlag && someCondition) {
   // ...
@@ -25,7 +25,7 @@ if (someFlag && someCondition) {
 
 ```typescript
 if (someCondition) {
-  const someFlag = await getFlag()
+  const someFlag = await getFlag();
   if (someFlag) {
     // ...
   }

.agents/skills/vercel-react-best-practices/rules/async-defer-await.md

@@ -13,15 +13,15 @@ Move `await` operations into the branches where they're actually used to avoid b
 
 ```typescript
 async function handleRequest(userId: string, skipProcessing: boolean) {
-  const userData = await fetchUserData(userId)
+  const userData = await fetchUserData(userId);
 
   if (skipProcessing) {
     // Returns immediately but still waited for userData
-    return { skipped: true }
+    return { skipped: true };
   }
 
   // Only this branch uses userData
-  return processUserData(userData)
+  return processUserData(userData);
 }
 ```
 
@@ -31,12 +31,12 @@ async function handleRequest(userId: string, skipProcessing: boolean) {
 async function handleRequest(userId: string, skipProcessing: boolean) {
   if (skipProcessing) {
     // Returns immediately without waiting
-    return { skipped: true }
+    return { skipped: true };
   }
 
   // Fetch only when needed
-  const userData = await fetchUserData(userId)
+  const userData = await fetchUserData(userId);
-  return processUserData(userData)
+  return processUserData(userData);
 }
 ```
 
@@ -45,35 +45,35 @@ async function handleRequest(userId: string, skipProcessing: boolean) {
 ```typescript
 // Incorrect: always fetches permissions
 async function updateResource(resourceId: string, userId: string) {
-  const permissions = await fetchPermissions(userId)
+  const permissions = await fetchPermissions(userId);
-  const resource = await getResource(resourceId)
+  const resource = await getResource(resourceId);
 
   if (!resource) {
-    return { error: 'Not found' }
+    return { error: 'Not found' };
   }
 
   if (!permissions.canEdit) {
-    return { error: 'Forbidden' }
+    return { error: 'Forbidden' };
   }
 
-  return await updateResourceData(resource, permissions)
+  return await updateResourceData(resource, permissions);
 }
 
 // Correct: fetches only when needed
 async function updateResource(resourceId: string, userId: string) {
-  const resource = await getResource(resourceId)
+  const resource = await getResource(resourceId);
 
   if (!resource) {
-    return { error: 'Not found' }
+    return { error: 'Not found' };
   }
 
-  const permissions = await fetchPermissions(userId)
+  const permissions = await fetchPermissions(userId);
 
   if (!permissions.canEdit) {
-    return { error: 'Forbidden' }
+    return { error: 'Forbidden' };
   }
 
-  return await updateResourceData(resource, permissions)
+  return await updateResourceData(resource, permissions);
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/async-dependencies.md

@@ -12,25 +12,26 @@ For operations with partial dependencies, use `better-all` to maximize paralleli
 **Incorrect (profile waits for config unnecessarily):**
 
 ```typescript
-const [user, config] = await Promise.all([
+const [user, config] = await Promise.all([fetchUser(), fetchConfig()]);
-  fetchUser(),
+const profile = await fetchProfile(user.id);
-  fetchConfig()
-])
-const profile = await fetchProfile(user.id)
 ```
 
 **Correct (config and profile run in parallel):**
 
 ```typescript
-import { all } from 'better-all'
+import { all } from 'better-all';
 
 const { user, config, profile } = await all({
-  async user() { return fetchUser() },
+  async user() {
-  async config() { return fetchConfig() },
+    return fetchUser();
+  },
+  async config() {
+    return fetchConfig();
+  },
   async profile() {
-    return fetchProfile((await this.$.user).id)
+    return fetchProfile((await this.$.user).id);
-  }
+  },
-})
+});
 ```
 
 **Alternative without extra dependencies:**
@@ -38,14 +39,14 @@ const { user, config, profile } = await all({
 We can also create all the promises first, and do `Promise.all()` at the end.
 
 ```typescript
-const userPromise = fetchUser()
+const userPromise = fetchUser();
-const profilePromise = userPromise.then(user => fetchProfile(user.id))
+const profilePromise = userPromise.then((user) => fetchProfile(user.id));
 
 const [user, config, profile] = await Promise.all([
   userPromise,
   fetchConfig(),
-  profilePromise
+  profilePromise,
-])
+]);
 ```
 
 Reference: [https://github.com/shuding/better-all](https://github.com/shuding/better-all)

.agents/skills/vercel-react-best-practices/rules/async-parallel.md

@@ -12,9 +12,9 @@ When async operations have no interdependencies, execute them concurrently using
 **Incorrect (sequential execution, 3 round trips):**
 
 ```typescript
-const user = await fetchUser()
+const user = await fetchUser();
-const posts = await fetchPosts()
+const posts = await fetchPosts();
-const comments = await fetchComments()
+const comments = await fetchComments();
 ```
 
 **Correct (parallel execution, 1 round trip):**
@@ -23,6 +23,6 @@ const comments = await fetchComments()
 const [user, posts, comments] = await Promise.all([
   fetchUser(),
   fetchPosts(),
-  fetchComments()
+  fetchComments(),
-])
+]);
 ```

.agents/skills/vercel-react-best-practices/rules/async-suspense-boundaries.md

@@ -13,7 +13,7 @@ Instead of awaiting data in async components before returning JSX, use Suspense
 
 ```tsx
 async function Page() {
-  const data = await fetchData() // Blocks entire page
+  const data = await fetchData(); // Blocks entire page
 
   return (
     <div>
@@ -24,7 +24,7 @@ async function Page() {
       </div>
       <div>Footer</div>
     </div>
-  )
+  );
 }
 ```
 
@@ -45,12 +45,12 @@ function Page() {
       </div>
       <div>Footer</div>
     </div>
-  )
+  );
 }
 
 async function DataDisplay() {
-  const data = await fetchData() // Only blocks this component
+  const data = await fetchData(); // Only blocks this component
-  return <div>{data.content}</div>
+  return <div>{data.content}</div>;
 }
 ```
 
@@ -61,7 +61,7 @@ Sidebar, Header, and Footer render immediately. Only DataDisplay waits for data.
 ```tsx
 function Page() {
   // Start fetch immediately, but don't await
-  const dataPromise = fetchData()
+  const dataPromise = fetchData();
 
   return (
     <div>
@@ -73,17 +73,17 @@ function Page() {
       </Suspense>
       <div>Footer</div>
     </div>
-  )
+  );
 }
 
 function DataDisplay({ dataPromise }: { dataPromise: Promise<Data> }) {
-  const data = use(dataPromise) // Unwraps the promise
+  const data = use(dataPromise); // Unwraps the promise
-  return <div>{data.content}</div>
+  return <div>{data.content}</div>;
 }
 
 function DataSummary({ dataPromise }: { dataPromise: Promise<Data> }) {
-  const data = use(dataPromise) // Reuses the same promise
+  const data = use(dataPromise); // Reuses the same promise
-  return <div>{data.summary}</div>
+  return <div>{data.summary}</div>;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/bundle-analyzable-paths.md

@@ -12,6 +12,7 @@ Build tools work best when import and file-system paths are obvious at build tim
 Prefer explicit maps or literal paths so the set of reachable files stays narrow and predictable. This is the same rule whether you are choosing modules with `import()` or reading files in server/build code.
 
 When analysis becomes too broad, the cost is real:
+
 - Larger server bundles
 - Slower builds
 - Worse cold starts
@@ -25,9 +26,9 @@ When analysis becomes too broad, the cost is real:
 const PAGE_MODULES = {
   home: './pages/home',
   settings: './pages/settings',
-} as const
+} as const;
 
-const Page = await import(PAGE_MODULES[pageName])
+const Page = await import(PAGE_MODULES[pageName]);
 ```
 
 **Correct (use an explicit map of allowed modules):**
@@ -36,9 +37,9 @@ const Page = await import(PAGE_MODULES[pageName])
 const PAGE_MODULES = {
   home: () => import('./pages/home'),
   settings: () => import('./pages/settings'),
-} as const
+} as const;
 
-const Page = await PAGE_MODULES[pageName]()
+const Page = await PAGE_MODULES[pageName]();
 ```
 
 ### File-System Paths
@@ -46,7 +47,7 @@ const Page = await PAGE_MODULES[pageName]()
 **Incorrect (a 2-value enum still hides the final path from static analysis):**
 
 ```ts
-const baseDir = path.join(process.cwd(), 'content/' + contentKind)
+const baseDir = path.join(process.cwd(), 'content/' + contentKind);
 ```
 
 **Correct (make each final path literal at the callsite):**
@@ -55,7 +56,7 @@ const baseDir = path.join(process.cwd(), 'content/' + contentKind)
 const baseDir =
   kind === ContentKind.Blog
     ? path.join(process.cwd(), 'content/blog')
-    : path.join(process.cwd(), 'content/docs')
+    : path.join(process.cwd(), 'content/docs');
 ```
 
 In Next.js server code, this matters for output file tracing too. `path.join(process.cwd(), someVar)` can widen the traced file set because Next.js statically analyze `import`, `require`, and `fs` usage.

.agents/skills/vercel-react-best-practices/rules/bundle-barrel-imports.md

@@ -16,11 +16,11 @@ Popular icon and component libraries can have **up to 10,000 re-exports** in the
 **Incorrect (imports entire library):**
 
 ```tsx
-import { Check, X, Menu } from 'lucide-react'
+import { Check, X, Menu } from 'lucide-react';
 // Loads 1,583 modules, takes ~2.8s extra in dev
 // Runtime cost: 200-800ms on every cold start
 
-import { Button, TextField } from '@mui/material'
+import { Button, TextField } from '@mui/material';
 // Loads 2,225 modules, takes ~4.2s extra in dev
 ```
 
@@ -30,14 +30,14 @@ import { Button, TextField } from '@mui/material'
 // next.config.js - automatically optimizes barrel imports at build time
 module.exports = {
   experimental: {
-    optimizePackageImports: ['lucide-react', '@mui/material']
+    optimizePackageImports: ['lucide-react', '@mui/material'],
-  }
+  },
-}
+};
 ```
 
 ```tsx
 // Keep the standard imports - Next.js transforms them to direct imports
-import { Check, X, Menu } from 'lucide-react'
+import { Check, X, Menu } from 'lucide-react';
 // Full TypeScript support, no manual path wrangling
 ```
 
@@ -46,8 +46,8 @@ This is the recommended approach because it preserves TypeScript type safety and
 **Correct - Direct imports (non-Next.js projects):**
 
 ```tsx
-import Button from '@mui/material/Button'
+import Button from '@mui/material/Button';
-import TextField from '@mui/material/TextField'
+import TextField from '@mui/material/TextField';
 // Loads only what you use
 ```
 

.agents/skills/vercel-react-best-practices/rules/bundle-conditional.md

@@ -12,19 +12,25 @@ Load large data or modules only when a feature is activated.
 **Example (lazy-load animation frames):**
 
 ```tsx
-function AnimationPlayer({ enabled, setEnabled }: { enabled: boolean; setEnabled: React.Dispatch<React.SetStateAction<boolean>> }) {
+function AnimationPlayer({
-  const [frames, setFrames] = useState<Frame[] | null>(null)
+  enabled,
+  setEnabled,
+}: {
+  enabled: boolean;
+  setEnabled: React.Dispatch<React.SetStateAction<boolean>>;
+}) {
+  const [frames, setFrames] = useState<Frame[] | null>(null);
 
   useEffect(() => {
     if (enabled && !frames && typeof window !== 'undefined') {
       import('./animation-frames.js')
-        .then(mod => setFrames(mod.frames))
+        .then((mod) => setFrames(mod.frames))
-        .catch(() => setEnabled(false))
+        .catch(() => setEnabled(false));
     }
-  }, [enabled, frames, setEnabled])
+  }, [enabled, frames, setEnabled]);
 
-  if (!frames) return <Skeleton />
+  if (!frames) return <Skeleton />;
-  return <Canvas frames={frames} />
+  return <Canvas frames={frames} />;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/bundle-defer-third-party.md

@@ -12,7 +12,7 @@ Analytics, logging, and error tracking don't block user interaction. Load them a
 **Incorrect (blocks initial bundle):**
 
 ```tsx
-import { Analytics } from '@vercel/analytics/react'
+import { Analytics } from '@vercel/analytics/react';
 
 export default function RootLayout({ children }) {
   return (
@@ -22,19 +22,19 @@ export default function RootLayout({ children }) {
         <Analytics />
       </body>
     </html>
-  )
+  );
 }
 ```
 
 **Correct (loads after hydration):**
 
 ```tsx
-import dynamic from 'next/dynamic'
+import dynamic from 'next/dynamic';
 
 const Analytics = dynamic(
-  () => import('@vercel/analytics/react').then(m => m.Analytics),
+  () => import('@vercel/analytics/react').then((m) => m.Analytics),
-  { ssr: false }
+  { ssr: false },
-)
+);
 
 export default function RootLayout({ children }) {
   return (
@@ -44,6 +44,6 @@ export default function RootLayout({ children }) {
         <Analytics />
       </body>
     </html>
-  )
+  );
 }
 ```

.agents/skills/vercel-react-best-practices/rules/bundle-dynamic-imports.md

@@ -12,24 +12,24 @@ Use `next/dynamic` to lazy-load large components not needed on initial render.
 **Incorrect (Monaco bundles with main chunk ~300KB):**
 
 ```tsx
-import { MonacoEditor } from './monaco-editor'
+import { MonacoEditor } from './monaco-editor';
 
 function CodePanel({ code }: { code: string }) {
-  return <MonacoEditor value={code} />
+  return <MonacoEditor value={code} />;
 }
 ```
 
 **Correct (Monaco loads on demand):**
 
 ```tsx
-import dynamic from 'next/dynamic'
+import dynamic from 'next/dynamic';
 
 const MonacoEditor = dynamic(
-  () => import('./monaco-editor').then(m => m.MonacoEditor),
+  () => import('./monaco-editor').then((m) => m.MonacoEditor),
-  { ssr: false }
+  { ssr: false },
-)
+);
 
 function CodePanel({ code }: { code: string }) {
-  return <MonacoEditor value={code} />
+  return <MonacoEditor value={code} />;
 }
 ```

.agents/skills/vercel-react-best-practices/rules/bundle-preload.md

@@ -15,19 +15,15 @@ Preload heavy bundles before they're needed to reduce perceived latency.
 function EditorButton({ onClick }: { onClick: () => void }) {
   const preload = () => {
     if (typeof window !== 'undefined') {
-      void import('./monaco-editor')
+      void import('./monaco-editor');
     }
-  }
+  };
 
   return (
-    <button
+    <button onMouseEnter={preload} onFocus={preload} onClick={onClick}>
-      onMouseEnter={preload}
-      onFocus={preload}
-      onClick={onClick}
-    >
       Open Editor
     </button>
-  )
+  );
 }
 ```
 
@@ -37,13 +33,13 @@ function EditorButton({ onClick }: { onClick: () => void }) {
 function FlagsProvider({ children, flags }: Props) {
   useEffect(() => {
     if (flags.editorEnabled && typeof window !== 'undefined') {
-      void import('./monaco-editor').then(mod => mod.init())
+      void import('./monaco-editor').then((mod) => mod.init());
     }
-  }, [flags.editorEnabled])
+  }, [flags.editorEnabled]);
 
-  return <FlagsContext.Provider value={flags}>
+  return (
-    {children}
+    <FlagsContext.Provider value={flags}>{children}</FlagsContext.Provider>
-  </FlagsContext.Provider>
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/client-event-listeners.md

@@ -16,12 +16,12 @@ function useKeyboardShortcut(key: string, callback: () => void) {
   useEffect(() => {
     const handler = (e: KeyboardEvent) => {
       if (e.metaKey && e.key === key) {
-        callback()
+        callback();
       }
-    }
+    };
-    window.addEventListener('keydown', handler)
+    window.addEventListener('keydown', handler);
-    return () => window.removeEventListener('keydown', handler)
+    return () => window.removeEventListener('keydown', handler);
-  }, [key, callback])
+  }, [key, callback]);
 }
 ```
 
@@ -30,45 +30,49 @@ When using the `useKeyboardShortcut` hook multiple times, each instance will reg
 **Correct (N instances = 1 listener):**
 
 ```tsx
-import useSWRSubscription from 'swr/subscription'
+import useSWRSubscription from 'swr/subscription';
 
 // Module-level Map to track callbacks per key
-const keyCallbacks = new Map<string, Set<() => void>>()
+const keyCallbacks = new Map<string, Set<() => void>>();
 
 function useKeyboardShortcut(key: string, callback: () => void) {
   // Register this callback in the Map
   useEffect(() => {
     if (!keyCallbacks.has(key)) {
-      keyCallbacks.set(key, new Set())
+      keyCallbacks.set(key, new Set());
     }
-    keyCallbacks.get(key)!.add(callback)
+    keyCallbacks.get(key)!.add(callback);
 
     return () => {
-      const set = keyCallbacks.get(key)
+      const set = keyCallbacks.get(key);
       if (set) {
-        set.delete(callback)
+        set.delete(callback);
         if (set.size === 0) {
-          keyCallbacks.delete(key)
+          keyCallbacks.delete(key);
         }
       }
-    }
+    };
-  }, [key, callback])
+  }, [key, callback]);
 
   useSWRSubscription('global-keydown', () => {
     const handler = (e: KeyboardEvent) => {
       if (e.metaKey && keyCallbacks.has(e.key)) {
-        keyCallbacks.get(e.key)!.forEach(cb => cb())
+        keyCallbacks.get(e.key)!.forEach((cb) => cb());
       }
-    }
+    };
-    window.addEventListener('keydown', handler)
+    window.addEventListener('keydown', handler);
-    return () => window.removeEventListener('keydown', handler)
+    return () => window.removeEventListener('keydown', handler);
-  })
+  });
 }
 
 function Profile() {
   // Multiple shortcuts will share the same listener
-  useKeyboardShortcut('p', () => { /* ... */ }) 
+  useKeyboardShortcut('p', () => {
-  useKeyboardShortcut('k', () => { /* ... */ })
+    /* ... */
+  });
+  useKeyboardShortcut('k', () => {
+    /* ... */
+  });
   // ...
 }
 ```

.agents/skills/vercel-react-best-practices/rules/client-localstorage-schema.md

@@ -13,18 +13,18 @@ Add version prefix to keys and store only needed fields. Prevents schema conflic
 
 ```typescript
 // No version, stores everything, no error handling
-localStorage.setItem('userConfig', JSON.stringify(fullUserObject))
+localStorage.setItem('userConfig', JSON.stringify(fullUserObject));
-const data = localStorage.getItem('userConfig')
+const data = localStorage.getItem('userConfig');
 ```
 
 **Correct:**
 
 ```typescript
-const VERSION = 'v2'
+const VERSION = 'v2';
 
 function saveConfig(config: { theme: string; language: string }) {
   try {
-    localStorage.setItem(`userConfig:${VERSION}`, JSON.stringify(config))
+    localStorage.setItem(`userConfig:${VERSION}`, JSON.stringify(config));
   } catch {
     // Throws in incognito/private browsing, quota exceeded, or disabled
   }
@@ -32,21 +32,24 @@ function saveConfig(config: { theme: string; language: string }) {
 
 function loadConfig() {
   try {
-    const data = localStorage.getItem(`userConfig:${VERSION}`)
+    const data = localStorage.getItem(`userConfig:${VERSION}`);
-    return data ? JSON.parse(data) : null
+    return data ? JSON.parse(data) : null;
   } catch {
-    return null
+    return null;
   }
 }
 
 // Migration from v1 to v2
 function migrate() {
   try {
-    const v1 = localStorage.getItem('userConfig:v1')
+    const v1 = localStorage.getItem('userConfig:v1');
     if (v1) {
-      const old = JSON.parse(v1)
+      const old = JSON.parse(v1);
-      saveConfig({ theme: old.darkMode ? 'dark' : 'light', language: old.lang })
+      saveConfig({
-      localStorage.removeItem('userConfig:v1')
+        theme: old.darkMode ? 'dark' : 'light',
+        language: old.lang,
+      });
+      localStorage.removeItem('userConfig:v1');
     }
   } catch {}
 }
@@ -58,10 +61,13 @@ function migrate() {
 // User object has 20+ fields, only store what UI needs
 function cachePrefs(user: FullUser) {
   try {
-    localStorage.setItem('prefs:v1', JSON.stringify({
+    localStorage.setItem(
-      theme: user.preferences.theme,
+      'prefs:v1',
-      notifications: user.preferences.notifications
+      JSON.stringify({
-    }))
+        theme: user.preferences.theme,
+        notifications: user.preferences.notifications,
+      }),
+    );
   } catch {}
 }
 ```

.agents/skills/vercel-react-best-practices/rules/client-passive-event-listeners.md

@@ -13,34 +13,34 @@ Add `{ passive: true }` to touch and wheel event listeners to enable immediate s
 
 ```typescript
 useEffect(() => {
-  const handleTouch = (e: TouchEvent) => console.log(e.touches[0].clientX)
+  const handleTouch = (e: TouchEvent) => console.log(e.touches[0].clientX);
-  const handleWheel = (e: WheelEvent) => console.log(e.deltaY)
+  const handleWheel = (e: WheelEvent) => console.log(e.deltaY);
 
-  document.addEventListener('touchstart', handleTouch)
+  document.addEventListener('touchstart', handleTouch);
-  document.addEventListener('wheel', handleWheel)
+  document.addEventListener('wheel', handleWheel);
 
   return () => {
-    document.removeEventListener('touchstart', handleTouch)
+    document.removeEventListener('touchstart', handleTouch);
-    document.removeEventListener('wheel', handleWheel)
+    document.removeEventListener('wheel', handleWheel);
-  }
+  };
-}, [])
+}, []);
 ```
 
 **Correct:**
 
 ```typescript
 useEffect(() => {
-  const handleTouch = (e: TouchEvent) => console.log(e.touches[0].clientX)
+  const handleTouch = (e: TouchEvent) => console.log(e.touches[0].clientX);
-  const handleWheel = (e: WheelEvent) => console.log(e.deltaY)
+  const handleWheel = (e: WheelEvent) => console.log(e.deltaY);
 
-  document.addEventListener('touchstart', handleTouch, { passive: true })
+  document.addEventListener('touchstart', handleTouch, { passive: true });
-  document.addEventListener('wheel', handleWheel, { passive: true })
+  document.addEventListener('wheel', handleWheel, { passive: true });
 
   return () => {
-    document.removeEventListener('touchstart', handleTouch)
+    document.removeEventListener('touchstart', handleTouch);
-    document.removeEventListener('wheel', handleWheel)
+    document.removeEventListener('wheel', handleWheel);
-  }
+  };
-}, [])
+}, []);
 ```
 
 **Use passive when:** tracking/analytics, logging, any listener that doesn't call `preventDefault()`.

.agents/skills/vercel-react-best-practices/rules/client-swr-dedup.md

@@ -13,43 +13,43 @@ SWR enables request deduplication, caching, and revalidation across component in
 
 ```tsx
 function UserList() {
-  const [users, setUsers] = useState([])
+  const [users, setUsers] = useState([]);
   useEffect(() => {
     fetch('/api/users')
-      .then(r => r.json())
+      .then((r) => r.json())
-      .then(setUsers)
+      .then(setUsers);
-  }, [])
+  }, []);
 }
 ```
 
 **Correct (multiple instances share one request):**
 
 ```tsx
-import useSWR from 'swr'
+import useSWR from 'swr';
 
 function UserList() {
-  const { data: users } = useSWR('/api/users', fetcher)
+  const { data: users } = useSWR('/api/users', fetcher);
 }
 ```
 
 **For immutable data:**
 
 ```tsx
-import { useImmutableSWR } from '@/lib/swr'
+import { useImmutableSWR } from '@/lib/swr';
 
 function StaticContent() {
-  const { data } = useImmutableSWR('/api/config', fetcher)
+  const { data } = useImmutableSWR('/api/config', fetcher);
 }
 ```
 
 **For mutations:**
 
 ```tsx
-import { useSWRMutation } from 'swr/mutation'
+import { useSWRMutation } from 'swr/mutation';
 
 function UpdateButton() {
-  const { trigger } = useSWRMutation('/api/user', updateUser)
+  const { trigger } = useSWRMutation('/api/user', updateUser);
-  return <button onClick={() => trigger()}>Update</button>
+  return <button onClick={() => trigger()}>Update</button>;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/js-batch-dom-css.md

@@ -10,55 +10,60 @@ tags: javascript, dom, css, performance, reflow, layout-thrashing
 Avoid interleaving style writes with layout reads. When you read a layout property (like `offsetWidth`, `getBoundingClientRect()`, or `getComputedStyle()`) between style changes, the browser is forced to trigger a synchronous reflow.
 
 **This is OK (browser batches style changes):**
+
 ```typescript
 function updateElementStyles(element: HTMLElement) {
   // Each line invalidates style, but browser batches the recalculation
-  element.style.width = '100px'
+  element.style.width = '100px';
-  element.style.height = '200px'
+  element.style.height = '200px';
-  element.style.backgroundColor = 'blue'
+  element.style.backgroundColor = 'blue';
-  element.style.border = '1px solid black'
+  element.style.border = '1px solid black';
 }
 ```
 
 **Incorrect (interleaved reads and writes force reflows):**
+
 ```typescript
 function layoutThrashing(element: HTMLElement) {
-  element.style.width = '100px'
+  element.style.width = '100px';
-  const width = element.offsetWidth  // Forces reflow
+  const width = element.offsetWidth; // Forces reflow
-  element.style.height = '200px'
+  element.style.height = '200px';
-  const height = element.offsetHeight  // Forces another reflow
+  const height = element.offsetHeight; // Forces another reflow
 }
 ```
 
 **Correct (batch writes, then read once):**
+
 ```typescript
 function updateElementStyles(element: HTMLElement) {
   // Batch all writes together
-  element.style.width = '100px'
+  element.style.width = '100px';
-  element.style.height = '200px'
+  element.style.height = '200px';
-  element.style.backgroundColor = 'blue'
+  element.style.backgroundColor = 'blue';
-  element.style.border = '1px solid black'
+  element.style.border = '1px solid black';
 
   // Read after all writes are done (single reflow)
-  const { width, height } = element.getBoundingClientRect()
+  const { width, height } = element.getBoundingClientRect();
 }
 ```
 
 **Correct (batch reads, then writes):**
+
 ```typescript
 function avoidThrashing(element: HTMLElement) {
   // Read phase - all layout queries first
-  const rect1 = element.getBoundingClientRect()
+  const rect1 = element.getBoundingClientRect();
-  const offsetWidth = element.offsetWidth
+  const offsetWidth = element.offsetWidth;
-  const offsetHeight = element.offsetHeight
+  const offsetHeight = element.offsetHeight;
 
   // Write phase - all style changes after
-  element.style.width = '100px'
+  element.style.width = '100px';
-  element.style.height = '200px'
+  element.style.height = '200px';
 }
 ```
 
 **Better: use CSS classes**
+
 ```css
 .highlighted-box {
   width: 100px;
@@ -67,38 +72,36 @@ function avoidThrashing(element: HTMLElement) {
   border: 1px solid black;
 }
 ```
+
 ```typescript
 function updateElementStyles(element: HTMLElement) {
-  element.classList.add('highlighted-box')
+  element.classList.add('highlighted-box');
 
-  const { width, height } = element.getBoundingClientRect()
+  const { width, height } = element.getBoundingClientRect();
 }
 ```
 
 **React example:**
+
 ```tsx
 // Incorrect: interleaving style changes with layout queries
 function Box({ isHighlighted }: { isHighlighted: boolean }) {
-  const ref = useRef<HTMLDivElement>(null)
+  const ref = useRef<HTMLDivElement>(null);
 
   useEffect(() => {
     if (ref.current && isHighlighted) {
-      ref.current.style.width = '100px'
+      ref.current.style.width = '100px';
-      const width = ref.current.offsetWidth // Forces layout
+      const width = ref.current.offsetWidth; // Forces layout
-      ref.current.style.height = '200px'
+      ref.current.style.height = '200px';
     }
-  }, [isHighlighted])
+  }, [isHighlighted]);
 
-  return <div ref={ref}>Content</div>
+  return <div ref={ref}>Content</div>;
 }
 
 // Correct: toggle class
 function Box({ isHighlighted }: { isHighlighted: boolean }) {
-  return (
+  return <div className={isHighlighted ? 'highlighted-box' : ''}>Content</div>;
-    <div className={isHighlighted ? 'highlighted-box' : ''}>
-      Content
-    </div>
-  )
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/js-cache-function-results.md

@@ -58,20 +58,20 @@ function ProjectList({ projects }: { projects: Project[] }) {
 **Simpler pattern for single-value functions:**
 
 ```typescript
-let isLoggedInCache: boolean | null = null
+let isLoggedInCache: boolean | null = null;
 
 function isLoggedIn(): boolean {
   if (isLoggedInCache !== null) {
-    return isLoggedInCache
+    return isLoggedInCache;
   }
 
-  isLoggedInCache = document.cookie.includes('auth=')
+  isLoggedInCache = document.cookie.includes('auth=');
-  return isLoggedInCache
+  return isLoggedInCache;
 }
 
 // Clear cache when auth changes
 function onAuthChange() {
-  isLoggedInCache = null
+  isLoggedInCache = null;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/js-cache-property-access.md

@@ -13,16 +13,16 @@ Cache object property lookups in hot paths.
 
 ```typescript
 for (let i = 0; i < arr.length; i++) {
-  process(obj.config.settings.value)
+  process(obj.config.settings.value);
 }
 ```
 
 **Correct (1 lookup total):**
 
 ```typescript
-const value = obj.config.settings.value
+const value = obj.config.settings.value;
-const len = arr.length
+const len = arr.length;
 for (let i = 0; i < len; i++) {
-  process(value)
+  process(value);
 }
 ```

.agents/skills/vercel-react-best-practices/rules/js-cache-storage.md

@@ -13,7 +13,7 @@ tags: javascript, localStorage, storage, caching, performance
 
 ```typescript
 function getTheme() {
-  return localStorage.getItem('theme') ?? 'light'
+  return localStorage.getItem('theme') ?? 'light';
 }
 // Called 10 times = 10 storage reads
 ```
@@ -21,18 +21,18 @@ function getTheme() {
 **Correct (Map cache):**
 
 ```typescript
-const storageCache = new Map<string, string | null>()
+const storageCache = new Map<string, string | null>();
 
 function getLocalStorage(key: string) {
   if (!storageCache.has(key)) {
-    storageCache.set(key, localStorage.getItem(key))
+    storageCache.set(key, localStorage.getItem(key));
   }
-  return storageCache.get(key)
+  return storageCache.get(key);
 }
 
 function setLocalStorage(key: string, value: string) {
-  localStorage.setItem(key, value)
+  localStorage.setItem(key, value);
-  storageCache.set(key, value)  // keep cache in sync
+  storageCache.set(key, value); // keep cache in sync
 }
 ```
 
@@ -41,15 +41,15 @@ Use a Map (not a hook) so it works everywhere: utilities, event handlers, not ju
 **Cookie caching:**
 
 ```typescript
-let cookieCache: Record<string, string> | null = null
+let cookieCache: Record<string, string> | null = null;
 
 function getCookie(name: string) {
   if (!cookieCache) {
     cookieCache = Object.fromEntries(
-      document.cookie.split('; ').map(c => c.split('='))
+      document.cookie.split('; ').map((c) => c.split('=')),
-    )
+    );
   }
-  return cookieCache[name]
+  return cookieCache[name];
 }
 ```
 
@@ -59,12 +59,12 @@ If storage can change externally (another tab, server-set cookies), invalidate c
 
 ```typescript
 window.addEventListener('storage', (e) => {
-  if (e.key) storageCache.delete(e.key)
+  if (e.key) storageCache.delete(e.key);
-})
+});
 
 document.addEventListener('visibilitychange', () => {
   if (document.visibilityState === 'visible') {
-    storageCache.clear()
+    storageCache.clear();
   }
-})
+});
 ```

.agents/skills/vercel-react-best-practices/rules/js-combine-iterations.md

@@ -12,21 +12,21 @@ Multiple `.filter()` or `.map()` calls iterate the array multiple times. Combine
 **Incorrect (3 iterations):**
 
 ```typescript
-const admins = users.filter(u => u.isAdmin)
+const admins = users.filter((u) => u.isAdmin);
-const testers = users.filter(u => u.isTester)
+const testers = users.filter((u) => u.isTester);
-const inactive = users.filter(u => !u.isActive)
+const inactive = users.filter((u) => !u.isActive);
 ```
 
 **Correct (1 iteration):**
 
 ```typescript
-const admins: User[] = []
+const admins: User[] = [];
-const testers: User[] = []
+const testers: User[] = [];
-const inactive: User[] = []
+const inactive: User[] = [];
 
 for (const user of users) {
-  if (user.isAdmin) admins.push(user)
+  if (user.isAdmin) admins.push(user);
-  if (user.isTester) testers.push(user)
+  if (user.isTester) testers.push(user);
-  if (!user.isActive) inactive.push(user)
+  if (!user.isActive) inactive.push(user);
 }
 ```

.agents/skills/vercel-react-best-practices/rules/js-early-exit.md

@@ -13,22 +13,22 @@ Return early when result is determined to skip unnecessary processing.
 
 ```typescript
 function validateUsers(users: User[]) {
-  let hasError = false
+  let hasError = false;
-  let errorMessage = ''
+  let errorMessage = '';
 
   for (const user of users) {
     if (!user.email) {
-      hasError = true
+      hasError = true;
-      errorMessage = 'Email required'
+      errorMessage = 'Email required';
     }
     if (!user.name) {
-      hasError = true
+      hasError = true;
-      errorMessage = 'Name required'
+      errorMessage = 'Name required';
     }
     // Continues checking all users even after error found
   }
 
-  return hasError ? { valid: false, error: errorMessage } : { valid: true }
+  return hasError ? { valid: false, error: errorMessage } : { valid: true };
 }
 ```
 
@@ -38,13 +38,13 @@ function validateUsers(users: User[]) {
 function validateUsers(users: User[]) {
   for (const user of users) {
     if (!user.email) {
-      return { valid: false, error: 'Email required' }
+      return { valid: false, error: 'Email required' };
     }
     if (!user.name) {
-      return { valid: false, error: 'Name required' }
+      return { valid: false, error: 'Name required' };
     }
   }
 
-  return { valid: true }
+  return { valid: true };
 }
 ```

.agents/skills/vercel-react-best-practices/rules/js-flatmap-filter.md

@@ -15,16 +15,14 @@ Chaining `.map().filter(Boolean)` creates an intermediate array and iterates twi
 
 ```typescript
 const userNames = users
-  .map(user => user.isActive ? user.name : null)
+  .map((user) => (user.isActive ? user.name : null))
-  .filter(Boolean)
+  .filter(Boolean);
 ```
 
 **Correct (1 iteration, no intermediate array):**
 
 ```typescript
-const userNames = users.flatMap(user =>
+const userNames = users.flatMap((user) => (user.isActive ? [user.name] : []));
-  user.isActive ? [user.name] : []
-)
 ```
 
 **More examples:**
@@ -33,28 +31,25 @@ const userNames = users.flatMap(user =>
 // Extract valid emails from responses
 // Before
 const emails = responses
-  .map(r => r.success ? r.data.email : null)
+  .map((r) => (r.success ? r.data.email : null))
-  .filter(Boolean)
+  .filter(Boolean);
 
 // After
-const emails = responses.flatMap(r =>
+const emails = responses.flatMap((r) => (r.success ? [r.data.email] : []));
-  r.success ? [r.data.email] : []
-)
 
 // Parse and filter valid numbers
 // Before
-const numbers = strings
+const numbers = strings.map((s) => parseInt(s, 10)).filter((n) => !isNaN(n));
-  .map(s => parseInt(s, 10))
-  .filter(n => !isNaN(n))
 
 // After
-const numbers = strings.flatMap(s => {
+const numbers = strings.flatMap((s) => {
-  const n = parseInt(s, 10)
+  const n = parseInt(s, 10);
-  return isNaN(n) ? [] : [n]
+  return isNaN(n) ? [] : [n];
-})
+});
 ```
 
 **When to use:**
+
 - Transforming items while filtering some out
 - Conditional mapping where some inputs produce no output
 - Parsing/validating where invalid inputs should be skipped

.agents/skills/vercel-react-best-practices/rules/js-hoist-regexp.md

@@ -39,7 +39,7 @@ function Highlighter({ text, query }: Props) {
 Global regex (`/g`) has mutable `lastIndex` state:
 
 ```typescript
-const regex = /foo/g
+const regex = /foo/g;
-regex.test('foo')  // true, lastIndex = 3
+regex.test('foo'); // true, lastIndex = 3
-regex.test('foo')  // false, lastIndex = 0
+regex.test('foo'); // false, lastIndex = 0
 ```

.agents/skills/vercel-react-best-practices/rules/js-index-maps.md

@@ -13,10 +13,10 @@ Multiple `.find()` calls by the same key should use a Map.
 
 ```typescript
 function processOrders(orders: Order[], users: User[]) {
-  return orders.map(order => ({
+  return orders.map((order) => ({
     ...order,
-    user: users.find(u => u.id === order.userId)
+    user: users.find((u) => u.id === order.userId),
-  }))
+  }));
 }
 ```
 
@@ -24,12 +24,12 @@ function processOrders(orders: Order[], users: User[]) {
 
 ```typescript
 function processOrders(orders: Order[], users: User[]) {
-  const userById = new Map(users.map(u => [u.id, u]))
+  const userById = new Map(users.map((u) => [u.id, u]));
 
-  return orders.map(order => ({
+  return orders.map((order) => ({
     ...order,
-    user: userById.get(order.userId)
+    user: userById.get(order.userId),
-  }))
+  }));
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/js-length-check-first.md

@@ -16,7 +16,7 @@ In real-world applications, this optimization is especially valuable when the co
 ```typescript
 function hasChanges(current: string[], original: string[]) {
   // Always sorts and joins, even when lengths differ
-  return current.sort().join() !== original.sort().join()
+  return current.sort().join() !== original.sort().join();
 }
 ```
 
@@ -28,21 +28,22 @@ Two O(n log n) sorts run even when `current.length` is 5 and `original.length` i
 function hasChanges(current: string[], original: string[]) {
   // Early return if lengths differ
   if (current.length !== original.length) {
-    return true
+    return true;
   }
   // Only sort when lengths match
-  const currentSorted = current.toSorted()
+  const currentSorted = current.toSorted();
-  const originalSorted = original.toSorted()
+  const originalSorted = original.toSorted();
   for (let i = 0; i < currentSorted.length; i++) {
     if (currentSorted[i] !== originalSorted[i]) {
-      return true
+      return true;
     }
   }
-  return false
+  return false;
 }
 ```
 
 This new approach is more efficient because:
+
 - It avoids the overhead of sorting and joining the arrays when lengths differ
 - It avoids consuming memory for the joined strings (especially important for large arrays)
 - It avoids mutating the original arrays

.agents/skills/vercel-react-best-practices/rules/js-min-max-loop.md

@@ -13,14 +13,14 @@ Finding the smallest or largest element only requires a single pass through the
 
 ```typescript
 interface Project {
-  id: string
+  id: string;
-  name: string
+  name: string;
-  updatedAt: number
+  updatedAt: number;
 }
 
 function getLatestProject(projects: Project[]) {
-  const sorted = [...projects].sort((a, b) => b.updatedAt - a.updatedAt)
+  const sorted = [...projects].sort((a, b) => b.updatedAt - a.updatedAt);
-  return sorted[0]
+  return sorted[0];
 }
 ```
 
@@ -30,8 +30,8 @@ Sorts the entire array just to find the maximum value.
 
 ```typescript
 function getOldestAndNewest(projects: Project[]) {
-  const sorted = [...projects].sort((a, b) => a.updatedAt - b.updatedAt)
+  const sorted = [...projects].sort((a, b) => a.updatedAt - b.updatedAt);
-  return { oldest: sorted[0], newest: sorted[sorted.length - 1] }
+  return { oldest: sorted[0], newest: sorted[sorted.length - 1] };
 }
 ```
 
@@ -41,31 +41,31 @@ Still sorts unnecessarily when only min/max are needed.
 
 ```typescript
 function getLatestProject(projects: Project[]) {
-  if (projects.length === 0) return null
+  if (projects.length === 0) return null;
 
-  let latest = projects[0]
+  let latest = projects[0];
 
   for (let i = 1; i < projects.length; i++) {
     if (projects[i].updatedAt > latest.updatedAt) {
-      latest = projects[i]
+      latest = projects[i];
     }
   }
 
-  return latest
+  return latest;
 }
 
 function getOldestAndNewest(projects: Project[]) {
-  if (projects.length === 0) return { oldest: null, newest: null }
+  if (projects.length === 0) return { oldest: null, newest: null };
 
-  let oldest = projects[0]
+  let oldest = projects[0];
-  let newest = projects[0]
+  let newest = projects[0];
 
   for (let i = 1; i < projects.length; i++) {
-    if (projects[i].updatedAt < oldest.updatedAt) oldest = projects[i]
+    if (projects[i].updatedAt < oldest.updatedAt) oldest = projects[i];
-    if (projects[i].updatedAt > newest.updatedAt) newest = projects[i]
+    if (projects[i].updatedAt > newest.updatedAt) newest = projects[i];
   }
 
-  return { oldest, newest }
+  return { oldest, newest };
 }
 ```
 
@@ -74,9 +74,9 @@ Single pass through the array, no copying, no sorting.
 **Alternative (Math.min/Math.max for small arrays):**
 
 ```typescript
-const numbers = [5, 2, 8, 1, 9]
+const numbers = [5, 2, 8, 1, 9];
-const min = Math.min(...numbers)
+const min = Math.min(...numbers);
-const max = Math.max(...numbers)
+const max = Math.max(...numbers);
 ```
 
 This works for small arrays, but can be slower or just throw an error for very large arrays due to spread operator limitations. Maximal array length is approximately 124000 in Chrome 143 and 638000 in Safari 18; exact numbers may vary - see [the fiddle](https://jsfiddle.net/qw1jabsx/4/). Use the loop approach for reliability.

.agents/skills/vercel-react-best-practices/rules/js-request-idle-callback.md

@@ -15,13 +15,13 @@ Use `requestIdleCallback()` to schedule non-critical work during browser idle pe
 
 ```typescript
 function handleSearch(query: string) {
-  const results = searchItems(query)
+  const results = searchItems(query);
-  setResults(results)
+  setResults(results);
 
   // These block the main thread immediately
-  analytics.track('search', { query })
+  analytics.track('search', { query });
-  saveToRecentSearches(query)
+  saveToRecentSearches(query);
-  prefetchTopResults(results.slice(0, 3))
+  prefetchTopResults(results.slice(0, 3));
 }
 ```
 
@@ -29,21 +29,21 @@ function handleSearch(query: string) {
 
 ```typescript
 function handleSearch(query: string) {
-  const results = searchItems(query)
+  const results = searchItems(query);
-  setResults(results)
+  setResults(results);
 
   // Defer non-critical work to idle periods
   requestIdleCallback(() => {
-    analytics.track('search', { query })
+    analytics.track('search', { query });
-  })
+  });
 
   requestIdleCallback(() => {
-    saveToRecentSearches(query)
+    saveToRecentSearches(query);
-  })
+  });
 
   requestIdleCallback(() => {
-    prefetchTopResults(results.slice(0, 3))
+    prefetchTopResults(results.slice(0, 3));
-  })
+  });
 }
 ```
 
@@ -53,41 +53,42 @@ function handleSearch(query: string) {
 // Ensure analytics fires within 2 seconds even if browser stays busy
 requestIdleCallback(
   () => analytics.track('page_view', { path: location.pathname }),
-  { timeout: 2000 }
+  { timeout: 2000 },
-)
+);
 ```
 
 **Chunking large tasks:**
 
 ```typescript
 function processLargeDataset(items: Item[]) {
-  let index = 0
+  let index = 0;
 
   function processChunk(deadline: IdleDeadline) {
     // Process items while we have idle time (aim for <50ms chunks)
     while (index < items.length && deadline.timeRemaining() > 0) {
-      processItem(items[index])
+      processItem(items[index]);
-      index++
+      index++;
     }
 
     // Schedule next chunk if more items remain
     if (index < items.length) {
-      requestIdleCallback(processChunk)
+      requestIdleCallback(processChunk);
     }
   }
 
-  requestIdleCallback(processChunk)
+  requestIdleCallback(processChunk);
 }
 ```
 
 **With fallback for unsupported browsers:**
 
 ```typescript
-const scheduleIdleWork = window.requestIdleCallback ?? ((cb: () => void) => setTimeout(cb, 1))
+const scheduleIdleWork =
+  window.requestIdleCallback ?? ((cb: () => void) => setTimeout(cb, 1));
 
 scheduleIdleWork(() => {
   // Non-critical work
-})
+});
 ```
 
 **When to use:**

.agents/skills/vercel-react-best-practices/rules/js-tosorted-immutable.md

@@ -46,7 +46,7 @@ function UserList({ users }: { users: User[] }) {
 
 ```typescript
 // Fallback for older browsers
-const sorted = [...items].sort((a, b) => a.value - b.value)
+const sorted = [...items].sort((a, b) => a.value - b.value);
 ```
 
 **Other immutable array methods:**

.agents/skills/vercel-react-best-practices/rules/rendering-activity.md

@@ -12,14 +12,14 @@ Use React's `<Activity>` to preserve state/DOM for expensive components that fre
 **Usage:**
 
 ```tsx
-import { Activity } from 'react'
+import { Activity } from 'react';
 
 function Dropdown({ isOpen }: Props) {
   return (
     <Activity mode={isOpen ? 'visible' : 'hidden'}>
       <ExpensiveMenu />
     </Activity>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-animate-svg-wrapper.md

@@ -14,15 +14,10 @@ Many browsers don't have hardware acceleration for CSS3 animations on SVG elemen
 ```tsx
 function LoadingSpinner() {
   return (
-    <svg 
+    <svg className="animate-spin" width="24" height="24" viewBox="0 0 24 24">
-      className="animate-spin"
-      width="24" 
-      height="24" 
-      viewBox="0 0 24 24"
-    >
       <circle cx="12" cy="12" r="10" stroke="currentColor" />
     </svg>
-  )
+  );
 }
 ```
 
@@ -32,15 +27,11 @@ function LoadingSpinner() {
 function LoadingSpinner() {
   return (
     <div className="animate-spin">
-      <svg 
+      <svg width="24" height="24" viewBox="0 0 24 24">
-        width="24" 
-        height="24" 
-        viewBox="0 0 24 24"
-      >
         <circle cx="12" cy="12" r="10" stroke="currentColor" />
       </svg>
     </div>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-conditional-render.md

@@ -13,11 +13,7 @@ Use explicit ternary operators (`? :`) instead of `&&` for conditional rendering
 
 ```tsx
 function Badge({ count }: { count: number }) {
-  return (
+  return <div>{count && <span className="badge">{count}</span>}</div>;
-    <div>
-      {count && <span className="badge">{count}</span>}
-    </div>
-  )
 }
 
 // When count = 0, renders: <div>0</div>
@@ -28,11 +24,7 @@ function Badge({ count }: { count: number }) {
 
 ```tsx
 function Badge({ count }: { count: number }) {
-  return (
+  return <div>{count > 0 ? <span className="badge">{count}</span> : null}</div>;
-    <div>
-      {count > 0 ? <span className="badge">{count}</span> : null}
-    </div>
-  )
 }
 
 // When count = 0, renders: <div></div>

.agents/skills/vercel-react-best-practices/rules/rendering-content-visibility.md

@@ -24,14 +24,14 @@ Apply `content-visibility: auto` to defer off-screen rendering.
 function MessageList({ messages }: { messages: Message[] }) {
   return (
     <div className="overflow-y-auto h-screen">
-      {messages.map(msg => (
+      {messages.map((msg) => (
         <div key={msg.id} className="message-item">
           <Avatar user={msg.author} />
           <div>{msg.content}</div>
         </div>
       ))}
     </div>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-hoist-jsx.md

@@ -13,31 +13,21 @@ Extract static JSX outside components to avoid re-creation.
 
 ```tsx
 function LoadingSkeleton() {
-  return <div className="animate-pulse h-20 bg-gray-200" />
+  return <div className="animate-pulse h-20 bg-gray-200" />;
 }
 
 function Container() {
-  return (
+  return <div>{loading && <LoadingSkeleton />}</div>;
-    <div>
-      {loading && <LoadingSkeleton />}
-    </div>
-  )
 }
 ```
 
 **Correct (reuses same element):**
 
 ```tsx
-const loadingSkeleton = (
+const loadingSkeleton = <div className="animate-pulse h-20 bg-gray-200" />;
-  <div className="animate-pulse h-20 bg-gray-200" />
-)
 
 function Container() {
-  return (
+  return <div>{loading && loadingSkeleton}</div>;
-    <div>
-      {loading && loadingSkeleton}
-    </div>
-  )
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-hydration-no-flicker.md

@@ -14,13 +14,9 @@ When rendering content that depends on client-side storage (localStorage, cookie
 ```tsx
 function ThemeWrapper({ children }: { children: ReactNode }) {
   // localStorage is not available on server - throws error
-  const theme = localStorage.getItem('theme') || 'light'
+  const theme = localStorage.getItem('theme') || 'light';
 
-  return (
+  return <div className={theme}>{children}</div>;
-    <div className={theme}>
-      {children}
-    </div>
-  )
 }
 ```
 
@@ -30,21 +26,17 @@ Server-side rendering will fail because `localStorage` is undefined.
 
 ```tsx
 function ThemeWrapper({ children }: { children: ReactNode }) {
-  const [theme, setTheme] = useState('light')
+  const [theme, setTheme] = useState('light');
 
   useEffect(() => {
     // Runs after hydration - causes visible flash
-    const stored = localStorage.getItem('theme')
+    const stored = localStorage.getItem('theme');
     if (stored) {
-      setTheme(stored)
+      setTheme(stored);
     }
-  }, [])
+  }, []);
 
-  return (
+  return <div className={theme}>{children}</div>;
-    <div className={theme}>
-      {children}
-    </div>
-  )
 }
 ```
 
@@ -56,9 +48,7 @@ Component first renders with default value (`light`), then updates after hydrati
 function ThemeWrapper({ children }: { children: ReactNode }) {
   return (
     <>
-      <div id="theme-wrapper">
+      <div id="theme-wrapper">{children}</div>
-        {children}
-      </div>
       <script
         dangerouslySetInnerHTML={{
           __html: `
@@ -73,7 +63,7 @@ function ThemeWrapper({ children }: { children: ReactNode }) {
         }}
       />
     </>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-hydration-suppress-warning.md

@@ -7,13 +7,13 @@ tags: rendering, hydration, ssr, nextjs
 
 ## Suppress Expected Hydration Mismatches
 
-In SSR frameworks (e.g., Next.js), some values are intentionally different on server vs client (random IDs, dates, locale/timezone formatting). For these *expected* mismatches, wrap the dynamic text in an element with `suppressHydrationWarning` to prevent noisy warnings. Do not use this to hide real bugs. Don’t overuse it.
+In SSR frameworks (e.g., Next.js), some values are intentionally different on server vs client (random IDs, dates, locale/timezone formatting). For these _expected_ mismatches, wrap the dynamic text in an element with `suppressHydrationWarning` to prevent noisy warnings. Do not use this to hide real bugs. Don’t overuse it.
 
 **Incorrect (known mismatch warnings):**
 
 ```tsx
 function Timestamp() {
-  return <span>{new Date().toLocaleString()}</span>
+  return <span>{new Date().toLocaleString()}</span>;
 }
 ```
 
@@ -21,10 +21,6 @@ function Timestamp() {
 
 ```tsx
 function Timestamp() {
-  return (
+  return <span suppressHydrationWarning>{new Date().toLocaleString()}</span>;
-    <span suppressHydrationWarning>
-      {new Date().toLocaleString()}
-    </span>
-  )
 }
 ```

.agents/skills/vercel-react-best-practices/rules/rendering-resource-hints.md

@@ -21,45 +21,49 @@ React DOM provides APIs to hint the browser about resources it will need. These
 **Example (preconnect to third-party APIs):**
 
 ```tsx
-import { preconnect, prefetchDNS } from 'react-dom'
+import { preconnect, prefetchDNS } from 'react-dom';
 
 export default function App() {
-  prefetchDNS('https://analytics.example.com')
+  prefetchDNS('https://analytics.example.com');
-  preconnect('https://api.example.com')
+  preconnect('https://api.example.com');
 
-  return <main>{/* content */}</main>
+  return <main>{/* content */}</main>;
 }
 ```
 
 **Example (preload critical fonts and styles):**
 
 ```tsx
-import { preload, preinit } from 'react-dom'
+import { preload, preinit } from 'react-dom';
 
 export default function RootLayout({ children }) {
   // Preload font file
-  preload('/fonts/inter.woff2', { as: 'font', type: 'font/woff2', crossOrigin: 'anonymous' })
+  preload('/fonts/inter.woff2', {
+    as: 'font',
+    type: 'font/woff2',
+    crossOrigin: 'anonymous',
+  });
 
   // Fetch and apply critical stylesheet immediately
-  preinit('/styles/critical.css', { as: 'style' })
+  preinit('/styles/critical.css', { as: 'style' });
 
   return (
     <html>
       <body>{children}</body>
     </html>
-  )
+  );
 }
 ```
 
 **Example (preload modules for code-split routes):**
 
 ```tsx
-import { preloadModule, preinitModule } from 'react-dom'
+import { preloadModule, preinitModule } from 'react-dom';
 
 function Navigation() {
   const preloadDashboard = () => {
-    preloadModule('/dashboard.js', { as: 'script' })
+    preloadModule('/dashboard.js', { as: 'script' });
-  }
+  };
 
   return (
     <nav>
@@ -67,19 +71,19 @@ function Navigation() {
         Dashboard
       </a>
     </nav>
-  )
+  );
 }
 ```
 
 **When to use each:**
 
-| API | Use case |
+| API             | Use case                                    |
-|-----|----------|
+| --------------- | ------------------------------------------- |
-| `prefetchDNS` | Third-party domains you'll connect to later |
+| `prefetchDNS`   | Third-party domains you'll connect to later |
-| `preconnect` | APIs or CDNs you'll fetch from immediately |
+| `preconnect`    | APIs or CDNs you'll fetch from immediately  |
-| `preload` | Critical resources needed for current page |
+| `preload`       | Critical resources needed for current page  |
-| `preloadModule` | JS modules for likely next navigation |
+| `preloadModule` | JS modules for likely next navigation       |
-| `preinit` | Stylesheets/scripts that must execute early |
+| `preinit`       | Stylesheets/scripts that must execute early |
-| `preinitModule` | ES modules that must execute early |
+| `preinitModule` | ES modules that must execute early          |
 
 Reference: [React DOM Resource Preloading APIs](https://react.dev/reference/react-dom#resource-preloading-apis)

.agents/skills/vercel-react-best-practices/rules/rendering-script-defer-async.md

@@ -28,7 +28,7 @@ export default function Document() {
       </head>
       <body>{/* content */}</body>
     </html>
-  )
+  );
 }
 ```
 
@@ -46,22 +46,25 @@ export default function Document() {
       </head>
       <body>{/* content */}</body>
     </html>
-  )
+  );
 }
 ```
 
 **Note:** In Next.js, prefer the `next/script` component with `strategy` prop instead of raw script tags:
 
 ```tsx
-import Script from 'next/script'
+import Script from 'next/script';
 
 export default function Page() {
   return (
     <>
-      <Script src="https://example.com/analytics.js" strategy="afterInteractive" />
+      <Script
+        src="https://example.com/analytics.js"
+        strategy="afterInteractive"
+      />
       <Script src="/scripts/utils.js" strategy="beforeInteractive" />
     </>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rendering-usetransition-loading.md

@@ -13,17 +13,17 @@ Use `useTransition` instead of manual `useState` for loading states. This provid
 
 ```tsx
 function SearchResults() {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
-  const [results, setResults] = useState([])
+  const [results, setResults] = useState([]);
-  const [isLoading, setIsLoading] = useState(false)
+  const [isLoading, setIsLoading] = useState(false);
 
   const handleSearch = async (value: string) => {
-    setIsLoading(true)
+    setIsLoading(true);
-    setQuery(value)
+    setQuery(value);
-    const data = await fetchResults(value)
+    const data = await fetchResults(value);
-    setResults(data)
+    setResults(data);
-    setIsLoading(false)
+    setIsLoading(false);
-  }
+  };
 
   return (
     <>
@@ -31,29 +31,29 @@ function SearchResults() {
       {isLoading && <Spinner />}
       <ResultsList results={results} />
     </>
-  )
+  );
 }
 ```
 
 **Correct (useTransition with built-in pending state):**
 
 ```tsx
-import { useTransition, useState } from 'react'
+import { useTransition, useState } from 'react';
 
 function SearchResults() {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
-  const [results, setResults] = useState([])
+  const [results, setResults] = useState([]);
-  const [isPending, startTransition] = useTransition()
+  const [isPending, startTransition] = useTransition();
 
   const handleSearch = (value: string) => {
-    setQuery(value) // Update input immediately
+    setQuery(value); // Update input immediately
 
     startTransition(async () => {
       // Fetch and update results
-      const data = await fetchResults(value)
+      const data = await fetchResults(value);
-      setResults(data)
+      setResults(data);
-    })
+    });
-  }
+  };
 
   return (
     <>
@@ -61,7 +61,7 @@ function SearchResults() {
       {isPending && <Spinner />}
       <ResultsList results={results} />
     </>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-defer-reads.md

@@ -13,14 +13,14 @@ Don't subscribe to dynamic state (searchParams, localStorage) if you only read i
 
 ```tsx
 function ShareButton({ chatId }: { chatId: string }) {
-  const searchParams = useSearchParams()
+  const searchParams = useSearchParams();
 
   const handleShare = () => {
-    const ref = searchParams.get('ref')
+    const ref = searchParams.get('ref');
-    shareChat(chatId, { ref })
+    shareChat(chatId, { ref });
-  }
+  };
 
-  return <button onClick={handleShare}>Share</button>
+  return <button onClick={handleShare}>Share</button>;
 }
 ```
 
@@ -29,11 +29,11 @@ function ShareButton({ chatId }: { chatId: string }) {
 ```tsx
 function ShareButton({ chatId }: { chatId: string }) {
   const handleShare = () => {
-    const params = new URLSearchParams(window.location.search)
+    const params = new URLSearchParams(window.location.search);
-    const ref = params.get('ref')
+    const ref = params.get('ref');
-    shareChat(chatId, { ref })
+    shareChat(chatId, { ref });
-  }
+  };
 
-  return <button onClick={handleShare}>Share</button>
+  return <button onClick={handleShare}>Share</button>;
 }
 ```

.agents/skills/vercel-react-best-practices/rules/rerender-dependencies.md

@@ -13,16 +13,16 @@ Specify primitive dependencies instead of objects to minimize effect re-runs.
 
 ```tsx
 useEffect(() => {
-  console.log(user.id)
+  console.log(user.id);
-}, [user])
+}, [user]);
 ```
 
 **Correct (re-runs only when id changes):**
 
 ```tsx
 useEffect(() => {
-  console.log(user.id)
+  console.log(user.id);
-}, [user.id])
+}, [user.id]);
 ```
 
 **For derived state, compute outside effect:**
@@ -31,15 +31,15 @@ useEffect(() => {
 // Incorrect: runs on width=767, 766, 765...
 useEffect(() => {
   if (width < 768) {
-    enableMobileMode()
+    enableMobileMode();
   }
-}, [width])
+}, [width]);
 
 // Correct: runs only on boolean transition
-const isMobile = width < 768
+const isMobile = width < 768;
 useEffect(() => {
   if (isMobile) {
-    enableMobileMode()
+    enableMobileMode();
   }
-}, [isMobile])
+}, [isMobile]);
 ```

.agents/skills/vercel-react-best-practices/rules/rerender-derived-state-no-effect.md

@@ -13,15 +13,15 @@ If a value can be computed from current props/state, do not store it in state or
 
 ```tsx
 function Form() {
-  const [firstName, setFirstName] = useState('First')
+  const [firstName, setFirstName] = useState('First');
-  const [lastName, setLastName] = useState('Last')
+  const [lastName, setLastName] = useState('Last');
-  const [fullName, setFullName] = useState('')
+  const [fullName, setFullName] = useState('');
 
   useEffect(() => {
-    setFullName(firstName + ' ' + lastName)
+    setFullName(firstName + ' ' + lastName);
-  }, [firstName, lastName])
+  }, [firstName, lastName]);
 
-  return <p>{fullName}</p>
+  return <p>{fullName}</p>;
 }
 ```
 
@@ -29,11 +29,11 @@ function Form() {
 
 ```tsx
 function Form() {
-  const [firstName, setFirstName] = useState('First')
+  const [firstName, setFirstName] = useState('First');
-  const [lastName, setLastName] = useState('Last')
+  const [lastName, setLastName] = useState('Last');
-  const fullName = firstName + ' ' + lastName
+  const fullName = firstName + ' ' + lastName;
 
-  return <p>{fullName}</p>
+  return <p>{fullName}</p>;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-derived-state.md

@@ -13,9 +13,9 @@ Subscribe to derived boolean state instead of continuous values to reduce re-ren
 
 ```tsx
 function Sidebar() {
-  const width = useWindowWidth()  // updates continuously
+  const width = useWindowWidth(); // updates continuously
-  const isMobile = width < 768
+  const isMobile = width < 768;
-  return <nav className={isMobile ? 'mobile' : 'desktop'} />
+  return <nav className={isMobile ? 'mobile' : 'desktop'} />;
 }
 ```
 
@@ -23,7 +23,7 @@ function Sidebar() {
 
 ```tsx
 function Sidebar() {
-  const isMobile = useMediaQuery('(max-width: 767px)')
+  const isMobile = useMediaQuery('(max-width: 767px)');
-  return <nav className={isMobile ? 'mobile' : 'desktop'} />
+  return <nav className={isMobile ? 'mobile' : 'desktop'} />;
 }
 ```

.agents/skills/vercel-react-best-practices/rules/rerender-functional-setstate.md

@@ -13,19 +13,22 @@ When updating state based on the current state value, use the functional update
 
 ```tsx
 function TodoList() {
-  const [items, setItems] = useState(initialItems)
+  const [items, setItems] = useState(initialItems);
 
   // Callback must depend on items, recreated on every items change
-  const addItems = useCallback((newItems: Item[]) => {
+  const addItems = useCallback(
-    setItems([...items, ...newItems])
+    (newItems: Item[]) => {
-  }, [items])  // ❌ items dependency causes recreations
+      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))
+    setItems(items.filter((item) => item.id !== id));
-  }, [])  // ❌ Missing items dependency - will use stale items!
+  }, []); // ❌ Missing items dependency - will use stale items!
 
-  return <ItemsEditor items={items} onAdd={addItems} onRemove={removeItem} />
+  return <ItemsEditor items={items} onAdd={addItems} onRemove={removeItem} />;
 }
 ```
 
@@ -35,19 +38,19 @@ The first callback is recreated every time `items` changes, which can cause chil
 
 ```tsx
 function TodoList() {
-  const [items, setItems] = useState(initialItems)
+  const [items, setItems] = useState(initialItems);
 
   // Stable callback, never recreated
   const addItems = useCallback((newItems: Item[]) => {
-    setItems(curr => [...curr, ...newItems])
+    setItems((curr) => [...curr, ...newItems]);
-  }, [])  // ✅ No dependencies needed
+  }, []); // ✅ No dependencies needed
 
   // Always uses latest state, no stale closure risk
   const removeItem = useCallback((id: string) => {
-    setItems(curr => curr.filter(item => item.id !== id))
+    setItems((curr) => curr.filter((item) => item.id !== id));
-  }, [])  // ✅ Safe and stable
+  }, []); // ✅ Safe and stable
 
-  return <ItemsEditor items={items} onAdd={addItems} onRemove={removeItem} />
+  return <ItemsEditor items={items} onAdd={addItems} onRemove={removeItem} />;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-lazy-state-init.md

@@ -14,20 +14,20 @@ Pass a function to `useState` for expensive initial values. Without the function
 ```tsx
 function FilteredList({ items }: { items: Item[] }) {
   // buildSearchIndex() runs on EVERY render, even after initialization
-  const [searchIndex, setSearchIndex] = useState(buildSearchIndex(items))
+  const [searchIndex, setSearchIndex] = useState(buildSearchIndex(items));
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
 
   // When query changes, buildSearchIndex runs again unnecessarily
-  return <SearchResults index={searchIndex} query={query} />
+  return <SearchResults index={searchIndex} query={query} />;
 }
 
 function UserProfile() {
   // JSON.parse runs on every render
   const [settings, setSettings] = useState(
-    JSON.parse(localStorage.getItem('settings') || '{}')
+    JSON.parse(localStorage.getItem('settings') || '{}'),
-  )
+  );
 
-  return <SettingsForm settings={settings} onChange={setSettings} />
+  return <SettingsForm settings={settings} onChange={setSettings} />;
 }
 ```
 
@@ -36,20 +36,20 @@ function UserProfile() {
 ```tsx
 function FilteredList({ items }: { items: Item[] }) {
   // buildSearchIndex() runs ONLY on initial render
-  const [searchIndex, setSearchIndex] = useState(() => buildSearchIndex(items))
+  const [searchIndex, setSearchIndex] = useState(() => buildSearchIndex(items));
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
 
-  return <SearchResults index={searchIndex} query={query} />
+  return <SearchResults index={searchIndex} query={query} />;
 }
 
 function UserProfile() {
   // JSON.parse runs only on initial render
   const [settings, setSettings] = useState(() => {
-    const stored = localStorage.getItem('settings')
+    const stored = localStorage.getItem('settings');
-    return stored ? JSON.parse(stored) : {}
+    return stored ? JSON.parse(stored) : {};
-  })
+  });
 
-  return <SettingsForm settings={settings} onChange={setSettings} />
+  return <SettingsForm settings={settings} onChange={setSettings} />;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-memo-with-default-value.md

@@ -1,10 +1,8 @@
 ---
-
 title: Extract Default Non-primitive Parameter Value from Memoized Component to Constant
 impact: MEDIUM
 impactDescription: restores memoization by using a constant for default value
 tags: rerender, memo, optimization
-
 ---
 
 ## Extract Default Non-primitive Parameter Value from Memoized Component to Constant

.agents/skills/vercel-react-best-practices/rules/rerender-memo.md

@@ -14,12 +14,12 @@ Extract expensive work into memoized components to enable early returns before c
 ```tsx
 function Profile({ user, loading }: Props) {
   const avatar = useMemo(() => {
-    const id = computeAvatarId(user)
+    const id = computeAvatarId(user);
-    return <Avatar id={id} />
+    return <Avatar id={id} />;
-  }, [user])
+  }, [user]);
 
-  if (loading) return <Skeleton />
+  if (loading) return <Skeleton />;
-  return <div>{avatar}</div>
+  return <div>{avatar}</div>;
 }
 ```
 
@@ -27,17 +27,17 @@ function Profile({ user, loading }: Props) {
 
 ```tsx
 const UserAvatar = memo(function UserAvatar({ user }: { user: User }) {
-  const id = useMemo(() => computeAvatarId(user), [user])
+  const id = useMemo(() => computeAvatarId(user), [user]);
-  return <Avatar id={id} />
+  return <Avatar id={id} />;
-})
+});
 
 function Profile({ user, loading }: Props) {
-  if (loading) return <Skeleton />
+  if (loading) return <Skeleton />;
   return (
     <div>
       <UserAvatar user={user} />
     </div>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-move-effect-to-event.md

@@ -13,17 +13,17 @@ If a side effect is triggered by a specific user action (submit, click, drag), r
 
 ```tsx
 function Form() {
-  const [submitted, setSubmitted] = useState(false)
+  const [submitted, setSubmitted] = useState(false);
-  const theme = useContext(ThemeContext)
+  const theme = useContext(ThemeContext);
 
   useEffect(() => {
     if (submitted) {
-      post('/api/register')
+      post('/api/register');
-      showToast('Registered', theme)
+      showToast('Registered', theme);
     }
-  }, [submitted, theme])
+  }, [submitted, theme]);
 
-  return <button onClick={() => setSubmitted(true)}>Submit</button>
+  return <button onClick={() => setSubmitted(true)}>Submit</button>;
 }
 ```
 
@@ -31,14 +31,14 @@ function Form() {
 
 ```tsx
 function Form() {
-  const theme = useContext(ThemeContext)
+  const theme = useContext(ThemeContext);
 
   function handleSubmit() {
-    post('/api/register')
+    post('/api/register');
-    showToast('Registered', theme)
+    showToast('Registered', theme);
   }
 
-  return <button onClick={handleSubmit}>Submit</button>
+  return <button onClick={handleSubmit}>Submit</button>;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-no-inline-components.md

@@ -23,7 +23,7 @@ function UserProfile({ user, theme }) {
       src={user.avatarUrl}
       className={theme === 'dark' ? 'avatar-dark' : 'avatar-light'}
     />
-  )
+  );
 
   // Defined inside to access `user` - BAD
   const Stats = () => (
@@ -31,14 +31,14 @@ function UserProfile({ user, theme }) {
       <span>{user.followers} followers</span>
       <span>{user.posts} posts</span>
     </div>
-  )
+  );
 
   return (
     <div>
       <Avatar />
       <Stats />
     </div>
-  )
+  );
 }
 ```
 
@@ -53,7 +53,7 @@ function Avatar({ src, theme }: { src: string; theme: string }) {
       src={src}
       className={theme === 'dark' ? 'avatar-dark' : 'avatar-light'}
     />
-  )
+  );
 }
 
 function Stats({ followers, posts }: { followers: number; posts: number }) {
@@ -62,7 +62,7 @@ function Stats({ followers, posts }: { followers: number; posts: number }) {
       <span>{followers} followers</span>
       <span>{posts} posts</span>
     </div>
-  )
+  );
 }
 
 function UserProfile({ user, theme }) {
@@ -71,11 +71,12 @@ function UserProfile({ user, theme }) {
       <Avatar src={user.avatarUrl} theme={theme} />
       <Stats followers={user.followers} posts={user.posts} />
     </div>
-  )
+  );
 }
 ```
 
 **Symptoms of this bug:**
+
 - Input fields lose focus on every keystroke
 - Animations restart unexpectedly
 - `useEffect` cleanup/setup runs on every parent render

.agents/skills/vercel-react-best-practices/rules/rerender-simple-expression-in-memo.md

@@ -15,10 +15,10 @@ Calling `useMemo` and comparing hook dependencies may consume more resources tha
 ```tsx
 function Header({ user, notifications }: Props) {
   const isLoading = useMemo(() => {
-    return user.isLoading || notifications.isLoading
+    return user.isLoading || notifications.isLoading;
-  }, [user.isLoading, notifications.isLoading])
+  }, [user.isLoading, notifications.isLoading]);
 
-  if (isLoading) return <Skeleton />
+  if (isLoading) return <Skeleton />;
   // return some markup
 }
 ```
@@ -27,9 +27,9 @@ function Header({ user, notifications }: Props) {
 
 ```tsx
 function Header({ user, notifications }: Props) {
-  const isLoading = user.isLoading || notifications.isLoading
+  const isLoading = user.isLoading || notifications.isLoading;
 
-  if (isLoading) return <Skeleton />
+  if (isLoading) return <Skeleton />;
   // return some markup
 }
 ```

.agents/skills/vercel-react-best-practices/rules/rerender-split-combined-hooks.md

@@ -13,12 +13,12 @@ When a hook contains multiple independent tasks with different dependencies, spl
 
 ```tsx
 const sortedProducts = useMemo(() => {
-  const filtered = products.filter((p) => p.category === category)
+  const filtered = products.filter((p) => p.category === category);
   const sorted = filtered.toSorted((a, b) =>
-    sortOrder === "asc" ? a.price - b.price : b.price - a.price
+    sortOrder === 'asc' ? a.price - b.price : b.price - a.price,
-  )
+  );
-  return sorted
+  return sorted;
-}, [products, category, sortOrder])
+}, [products, category, sortOrder]);
 ```
 
 **Correct (filtering only recomputes when products or category change):**
@@ -26,16 +26,16 @@ const sortedProducts = useMemo(() => {
 ```tsx
 const filteredProducts = useMemo(
   () => products.filter((p) => p.category === category),
-  [products, category]
+  [products, category],
-)
+);
 
 const sortedProducts = useMemo(
   () =>
     filteredProducts.toSorted((a, b) =>
-      sortOrder === "asc" ? a.price - b.price : b.price - a.price
+      sortOrder === 'asc' ? a.price - b.price : b.price - a.price,
     ),
-  [filteredProducts, sortOrder]
+  [filteredProducts, sortOrder],
-)
+);
 ```
 
 This pattern also applies to `useEffect` when combining unrelated side effects:
@@ -44,21 +44,21 @@ This pattern also applies to `useEffect` when combining unrelated side effects:
 
 ```tsx
 useEffect(() => {
-  analytics.trackPageView(pathname)
+  analytics.trackPageView(pathname);
-  document.title = `${pageTitle} | My App`
+  document.title = `${pageTitle} | My App`;
-}, [pathname, pageTitle])
+}, [pathname, pageTitle]);
 ```
 
 **Correct (effects run independently):**
 
 ```tsx
 useEffect(() => {
-  analytics.trackPageView(pathname)
+  analytics.trackPageView(pathname);
-}, [pathname])
+}, [pathname]);
 
 useEffect(() => {
-  document.title = `${pageTitle} | My App`
+  document.title = `${pageTitle} | My App`;
-}, [pageTitle])
+}, [pageTitle]);
 ```
 
 **Note:** If your project has [React Compiler](https://react.dev/learn/react-compiler) enabled, it automatically optimizes dependency tracking and may handle some of these cases for you.

.agents/skills/vercel-react-best-practices/rules/rerender-transitions.md

@@ -13,28 +13,28 @@ Mark frequent, non-urgent state updates as transitions to maintain UI responsive
 
 ```tsx
 function ScrollTracker() {
-  const [scrollY, setScrollY] = useState(0)
+  const [scrollY, setScrollY] = useState(0);
   useEffect(() => {
-    const handler = () => setScrollY(window.scrollY)
+    const handler = () => setScrollY(window.scrollY);
-    window.addEventListener('scroll', handler, { passive: true })
+    window.addEventListener('scroll', handler, { passive: true });
-    return () => window.removeEventListener('scroll', handler)
+    return () => window.removeEventListener('scroll', handler);
-  }, [])
+  }, []);
 }
 ```
 
 **Correct (non-blocking updates):**
 
 ```tsx
-import { startTransition } from 'react'
+import { startTransition } from 'react';
 
 function ScrollTracker() {
-  const [scrollY, setScrollY] = useState(0)
+  const [scrollY, setScrollY] = useState(0);
   useEffect(() => {
     const handler = () => {
-      startTransition(() => setScrollY(window.scrollY))
+      startTransition(() => setScrollY(window.scrollY));
-    }
+    };
-    window.addEventListener('scroll', handler, { passive: true })
+    window.addEventListener('scroll', handler, { passive: true });
-    return () => window.removeEventListener('scroll', handler)
+    return () => window.removeEventListener('scroll', handler);
-  }, [])
+  }, []);
 }
 ```

.agents/skills/vercel-react-best-practices/rules/rerender-use-deferred-value.md

@@ -13,15 +13,15 @@ When user input triggers expensive computations or renders, use `useDeferredValu
 
 ```tsx
 function Search({ items }: { items: Item[] }) {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
-  const filtered = items.filter(item => fuzzyMatch(item, query))
+  const filtered = items.filter((item) => fuzzyMatch(item, query));
 
   return (
     <>
-      <input value={query} onChange={e => setQuery(e.target.value)} />
+      <input value={query} onChange={(e) => setQuery(e.target.value)} />
       <ResultsList results={filtered} />
     </>
-  )
+  );
 }
 ```
 
@@ -29,22 +29,22 @@ function Search({ items }: { items: Item[] }) {
 
 ```tsx
 function Search({ items }: { items: Item[] }) {
-  const [query, setQuery] = useState('')
+  const [query, setQuery] = useState('');
-  const deferredQuery = useDeferredValue(query)
+  const deferredQuery = useDeferredValue(query);
   const filtered = useMemo(
-    () => items.filter(item => fuzzyMatch(item, deferredQuery)),
+    () => items.filter((item) => fuzzyMatch(item, deferredQuery)),
-    [items, deferredQuery]
+    [items, deferredQuery],
-  )
+  );
-  const isStale = query !== deferredQuery
+  const isStale = query !== deferredQuery;
 
   return (
     <>
-      <input value={query} onChange={e => setQuery(e.target.value)} />
+      <input value={query} onChange={(e) => setQuery(e.target.value)} />
       <div style={{ opacity: isStale ? 0.7 : 1 }}>
         <ResultsList results={filtered} />
       </div>
     </>
-  )
+  );
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/rerender-use-ref-transient-values.md

@@ -13,13 +13,13 @@ When a value changes frequently and you don't want a re-render on every update (
 
 ```tsx
 function Tracker() {
-  const [lastX, setLastX] = useState(0)
+  const [lastX, setLastX] = useState(0);
 
   useEffect(() => {
-    const onMove = (e: MouseEvent) => setLastX(e.clientX)
+    const onMove = (e: MouseEvent) => setLastX(e.clientX);
-    window.addEventListener('mousemove', onMove)
+    window.addEventListener('mousemove', onMove);
-    return () => window.removeEventListener('mousemove', onMove)
+    return () => window.removeEventListener('mousemove', onMove);
-  }, [])
+  }, []);
 
   return (
     <div
@@ -32,7 +32,7 @@ function Tracker() {
         background: 'black',
       }}
     />
-  )
+  );
 }
 ```
 
@@ -40,20 +40,20 @@ function Tracker() {
 
 ```tsx
 function Tracker() {
-  const lastXRef = useRef(0)
+  const lastXRef = useRef(0);
-  const dotRef = useRef<HTMLDivElement>(null)
+  const dotRef = useRef<HTMLDivElement>(null);
 
   useEffect(() => {
     const onMove = (e: MouseEvent) => {
-      lastXRef.current = e.clientX
+      lastXRef.current = e.clientX;
-      const node = dotRef.current
+      const node = dotRef.current;
       if (node) {
-        node.style.transform = `translateX(${e.clientX}px)`
+        node.style.transform = `translateX(${e.clientX}px)`;
       }
-    }
+    };
-    window.addEventListener('mousemove', onMove)
+    window.addEventListener('mousemove', onMove);
-    return () => window.removeEventListener('mousemove', onMove)
+    return () => window.removeEventListener('mousemove', onMove);
-  }, [])
+  }, []);
 
   return (
     <div
@@ -68,6 +68,6 @@ function Tracker() {
         transform: 'translateX(0px)',
       }}
     />
-  )
+  );
 }
 ```

.agents/skills/vercel-react-best-practices/rules/server-after-nonblocking.md

@@ -12,46 +12,47 @@ Use Next.js's `after()` to schedule work that should execute after a response is
 **Incorrect (blocks response):**
 
 ```tsx
-import { logUserAction } from '@/app/utils'
+import { logUserAction } from '@/app/utils';
 
 export async function POST(request: Request) {
   // Perform mutation
-  await updateDatabase(request)
+  await updateDatabase(request);
 
   // Logging blocks the response
-  const userAgent = request.headers.get('user-agent') || 'unknown'
+  const userAgent = request.headers.get('user-agent') || 'unknown';
-  await logUserAction({ userAgent })
+  await logUserAction({ userAgent });
 
   return new Response(JSON.stringify({ status: 'success' }), {
     status: 200,
-    headers: { 'Content-Type': 'application/json' }
+    headers: { 'Content-Type': 'application/json' },
-  })
+  });
 }
 ```
 
 **Correct (non-blocking):**
 
 ```tsx
-import { after } from 'next/server'
+import { after } from 'next/server';
-import { headers, cookies } from 'next/headers'
+import { headers, cookies } from 'next/headers';
-import { logUserAction } from '@/app/utils'
+import { logUserAction } from '@/app/utils';
 
 export async function POST(request: Request) {
   // Perform mutation
-  await updateDatabase(request)
+  await updateDatabase(request);
 
   // Log after response is sent
   after(async () => {
-    const userAgent = (await headers()).get('user-agent') || 'unknown'
+    const userAgent = (await headers()).get('user-agent') || 'unknown';
-    const sessionCookie = (await cookies()).get('session-id')?.value || 'anonymous'
+    const sessionCookie =
+      (await cookies()).get('session-id')?.value || 'anonymous';
 
-    logUserAction({ sessionCookie, userAgent })
+    logUserAction({ sessionCookie, userAgent });
-  })
+  });
 
   return new Response(JSON.stringify({ status: 'success' }), {
     status: 200,
-    headers: { 'Content-Type': 'application/json' }
+    headers: { 'Content-Type': 'application/json' },
-  })
+  });
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/server-auth-actions.md

@@ -16,68 +16,68 @@ Next.js documentation explicitly states: "Treat Server Actions with the same sec
 **Incorrect (no authentication check):**
 
 ```typescript
-'use server'
+'use server';
 
 export async function deleteUser(userId: string) {
   // Anyone can call this! No auth check
-  await db.user.delete({ where: { id: userId } })
+  await db.user.delete({ where: { id: userId } });
-  return { success: true }
+  return { success: true };
 }
 ```
 
 **Correct (authentication inside the action):**
 
 ```typescript
-'use server'
+'use server';
 
-import { verifySession } from '@/lib/auth'
+import { verifySession } from '@/lib/auth';
-import { unauthorized } from '@/lib/errors'
+import { unauthorized } from '@/lib/errors';
 
 export async function deleteUser(userId: string) {
   // Always check auth inside the action
-  const session = await verifySession()
+  const session = await verifySession();
 
   if (!session) {
-    throw unauthorized('Must be logged in')
+    throw unauthorized('Must be logged in');
   }
 
   // Check authorization too
   if (session.user.role !== 'admin' && session.user.id !== userId) {
-    throw unauthorized('Cannot delete other users')
+    throw unauthorized('Cannot delete other users');
   }
 
-  await db.user.delete({ where: { id: userId } })
+  await db.user.delete({ where: { id: userId } });
-  return { success: true }
+  return { success: true };
 }
 ```
 
 **With input validation:**
 
 ```typescript
-'use server'
+'use server';
 
-import { verifySession } from '@/lib/auth'
+import { verifySession } from '@/lib/auth';
-import { z } from 'zod'
+import { z } from 'zod';
 
 const updateProfileSchema = z.object({
   userId: z.string().uuid(),
   name: z.string().min(1).max(100),
-  email: z.string().email()
+  email: z.string().email(),
-})
+});
 
 export async function updateProfile(data: unknown) {
   // Validate input first
-  const validated = updateProfileSchema.parse(data)
+  const validated = updateProfileSchema.parse(data);
 
   // Then authenticate
-  const session = await verifySession()
+  const session = await verifySession();
   if (!session) {
-    throw new Error('Unauthorized')
+    throw new Error('Unauthorized');
   }
 
   // Then authorize
   if (session.user.id !== validated.userId) {
-    throw new Error('Can only update own profile')
+    throw new Error('Can only update own profile');
   }
 
   // Finally perform the mutation
@@ -85,11 +85,11 @@ export async function updateProfile(data: unknown) {
     where: { id: validated.userId },
     data: {
       name: validated.name,
-      email: validated.email
+      email: validated.email,
-    }
+    },
-  })
+  });
 
-  return { success: true }
+  return { success: true };
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/server-cache-lru.md

@@ -12,20 +12,20 @@ tags: server, cache, lru, cross-request
 **Implementation:**
 
 ```typescript
-import { LRUCache } from 'lru-cache'
+import { LRUCache } from 'lru-cache';
 
 const cache = new LRUCache<string, any>({
   max: 1000,
-  ttl: 5 * 60 * 1000  // 5 minutes
+  ttl: 5 * 60 * 1000, // 5 minutes
-})
+});
 
 export async function getUser(id: string) {
-  const cached = cache.get(id)
+  const cached = cache.get(id);
-  if (cached) return cached
+  if (cached) return cached;
 
-  const user = await db.user.findUnique({ where: { id } })
+  const user = await db.user.findUnique({ where: { id } });
-  cache.set(id, user)
+  cache.set(id, user);
-  return user
+  return user;
 }
 
 // Request 1: DB query, result cached

.agents/skills/vercel-react-best-practices/rules/server-cache-react.md

@@ -12,15 +12,15 @@ Use `React.cache()` for server-side request deduplication. Authentication and da
 **Usage:**
 
 ```typescript
-import { cache } from 'react'
+import { cache } from 'react';
 
 export const getCurrentUser = cache(async () => {
-  const session = await auth()
+  const session = await auth();
-  if (!session?.user?.id) return null
+  if (!session?.user?.id) return null;
   return await db.user.findUnique({
-    where: { id: session.user.id }
+    where: { id: session.user.id },
-  })
+  });
-})
+});
 ```
 
 Within a single request, multiple calls to `getCurrentUser()` execute the query only once.
@@ -33,32 +33,32 @@ Within a single request, multiple calls to `getCurrentUser()` execute the query
 
 ```typescript
 const getUser = cache(async (params: { uid: number }) => {
-  return await db.user.findUnique({ where: { id: params.uid } })
+  return await db.user.findUnique({ where: { id: params.uid } });
-})
+});
 
 // Each call creates new object, never hits cache
-getUser({ uid: 1 })
+getUser({ uid: 1 });
-getUser({ uid: 1 })  // Cache miss, runs query again
+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 } })
+  return await db.user.findUnique({ where: { id: uid } });
-})
+});
 
 // Primitive args use value equality
-getUser(1)
+getUser(1);
-getUser(1)  // Cache hit, returns cached result
+getUser(1); // Cache hit, returns cached result
 ```
 
 If you must pass objects, pass the same reference:
 
 ```typescript
-const params = { uid: 1 }
+const params = { uid: 1 };
-getUser(params)  // Query runs
+getUser(params); // Query runs
-getUser(params)  // Cache hit (same reference)
+getUser(params); // Cache hit (same reference)
 ```
 
 **Next.js-Specific Note:**

.agents/skills/vercel-react-best-practices/rules/server-dedup-props.md

@@ -22,11 +22,11 @@ RSC→client serialization deduplicates by object reference, not value. Same ref
 
 ```tsx
 // RSC: send once
-<ClientList usernames={usernames} />
+<ClientList usernames={usernames} />;
 
 // Client: transform there
-'use client'
+('use client');
-const sorted = useMemo(() => [...usernames].sort(), [usernames])
+const sorted = useMemo(() => [...usernames].sort(), [usernames]);
 ```
 
 **Nested deduplication behavior:**

.agents/skills/vercel-react-best-practices/rules/server-hoist-static-io.md

@@ -97,35 +97,31 @@ export async function GET(request: Request) {
 **Incorrect (reads config on every call):**
 
 ```typescript
-import fs from 'node:fs/promises'
+import fs from 'node:fs/promises';
 
 export async function processRequest(data: Data) {
-  const config = JSON.parse(
+  const config = JSON.parse(await fs.readFile('./config.json', 'utf-8'));
-    await fs.readFile('./config.json', 'utf-8')
+  const template = await fs.readFile('./template.html', 'utf-8');
-  )
-  const template = await fs.readFile('./template.html', 'utf-8')
 
-  return render(template, data, config)
+  return render(template, data, config);
 }
 ```
 
 **Correct (hoists config and template to module level):**
 
 ```typescript
-import fs from 'node:fs/promises'
+import fs from 'node:fs/promises';
 
-const configPromise = fs
+const configPromise = fs.readFile('./config.json', 'utf-8').then(JSON.parse);
-  .readFile('./config.json', 'utf-8')
+const templatePromise = fs.readFile('./template.html', 'utf-8');
-  .then(JSON.parse)
-const templatePromise = fs.readFile('./template.html', 'utf-8')
 
 export async function processRequest(data: Data) {
   const [config, template] = await Promise.all([
     configPromise,
     templatePromise,
-  ])
+  ]);
 
-  return render(template, data, config)
+  return render(template, data, config);
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/server-no-shared-module-state.md

@@ -14,15 +14,15 @@ Treat module scope on the server as process-wide shared memory, not request-loca
 **Incorrect (request data leaks across concurrent renders):**
 
 ```tsx
-let currentUser: User | null = null
+let currentUser: User | null = null;
 
 export default async function Page() {
-  currentUser = await auth()
+  currentUser = await auth();
-  return <Dashboard />
+  return <Dashboard />;
 }
 
 async function Dashboard() {
-  return <div>{currentUser?.name}</div>
+  return <div>{currentUser?.name}</div>;
 }
 ```
 
@@ -32,12 +32,12 @@ If two requests overlap, request A can set `currentUser`, then request B overwri
 
 ```tsx
 export default async function Page() {
-  const user = await auth()
+  const user = await auth();
-  return <Dashboard user={user} />
+  return <Dashboard user={user} />;
 }
 
 function Dashboard({ user }: { user: User | null }) {
-  return <div>{user?.name}</div>
+  return <div>{user?.name}</div>;
 }
 ```
 

.agents/skills/vercel-react-best-practices/rules/server-parallel-fetching.md

@@ -13,18 +13,18 @@ React Server Components execute sequentially within a tree. Restructure with com
 
 ```tsx
 export default async function Page() {
-  const header = await fetchHeader()
+  const header = await fetchHeader();
   return (
     <div>
       <div>{header}</div>
       <Sidebar />
     </div>
-  )
+  );
 }
 
 async function Sidebar() {
-  const items = await fetchSidebarItems()
+  const items = await fetchSidebarItems();
-  return <nav>{items.map(renderItem)}</nav>
+  return <nav>{items.map(renderItem)}</nav>;
 }
 ```
 
@@ -32,13 +32,13 @@ async function Sidebar() {
 
 ```tsx
 async function Header() {
-  const data = await fetchHeader()
+  const data = await fetchHeader();
-  return <div>{data}</div>
+  return <div>{data}</div>;
 }
 
 async function Sidebar() {
-  const items = await fetchSidebarItems()
+  const items = await fetchSidebarItems();
-  return <nav>{items.map(renderItem)}</nav>
+  return <nav>{items.map(renderItem)}</nav>;
 }
 
 export default function Page() {
@@ -47,7 +47,7 @@ export default function Page() {
       <Header />
       <Sidebar />
     </div>
-  )
+  );
 }
 ```
 
@@ -55,13 +55,13 @@ export default function Page() {
 
 ```tsx
 async function Header() {
-  const data = await fetchHeader()
+  const data = await fetchHeader();
-  return <div>{data}</div>
+  return <div>{data}</div>;
 }
 
 async function Sidebar() {
-  const items = await fetchSidebarItems()
+  const items = await fetchSidebarItems();
-  return <nav>{items.map(renderItem)}</nav>
+  return <nav>{items.map(renderItem)}</nav>;
 }
 
 function Layout({ children }: { children: ReactNode }) {
@@ -70,7 +70,7 @@ function Layout({ children }: { children: ReactNode }) {
       <Header />
       {children}
     </div>
-  )
+  );
 }
 
 export default function Page() {
@@ -78,6 +78,6 @@ export default function Page() {
     <Layout>
       <Sidebar />
     </Layout>
-  )
+  );
 }
 ```

.agents/skills/vercel-react-best-practices/rules/server-parallel-nested-fetching.md

@@ -12,13 +12,11 @@ When fetching nested data in parallel, chain dependent fetches within each item'
 **Incorrect (a single slow item blocks all nested fetches):**
 
 ```tsx
-const chats = await Promise.all(
+const chats = await Promise.all(chatIds.map((id) => getChat(id)));
-  chatIds.map(id => getChat(id))
-)
 
 const chatAuthors = await Promise.all(
-  chats.map(chat => getUser(chat.author))
+  chats.map((chat) => getUser(chat.author)),
-)
+);
 ```
 
 If one `getChat(id)` out of 100 is extremely slow, the authors of the other 99 chats can't start loading even though their data is ready.
@@ -27,8 +25,8 @@ If one `getChat(id)` out of 100 is extremely slow, the authors of the other 99 c
 
 ```tsx
 const chatAuthors = await Promise.all(
-  chatIds.map(id => getChat(id).then(chat => getUser(chat.author)))
+  chatIds.map((id) => getChat(id).then((chat) => getUser(chat.author))),
-)
+);
 ```
 
 Each item independently chains `getChat` → `getUser`, so a slow chat doesn't block author fetches for the others.

.agents/skills/vercel-react-best-practices/rules/server-serialization.md

@@ -13,13 +13,13 @@ The React Server/Client boundary serializes all object properties into strings a
 
 ```tsx
 async function Page() {
-  const user = await fetchUser()  // 50 fields
+  const user = await fetchUser(); // 50 fields
-  return <Profile user={user} />
+  return <Profile user={user} />;
 }
 
-'use client'
+('use client');
 function Profile({ user }: { user: User }) {
-  return <div>{user.name}</div>  // uses 1 field
+  return <div>{user.name}</div>; // uses 1 field
 }
 ```
 
@@ -27,12 +27,12 @@ function Profile({ user }: { user: User }) {
 
 ```tsx
 async function Page() {
-  const user = await fetchUser()
+  const user = await fetchUser();
-  return <Profile name={user.name} />
+  return <Profile name={user.name} />;
 }
 
-'use client'
+('use client');
 function Profile({ name }: { name: string }) {
-  return <div>{name}</div>
+  return <div>{name}</div>;
 }
 ```

package-lock.json

@@ -8,6 +8,7 @@
       "name": "mcma-webui",
       "version": "1.0.0",
       "dependencies": {
+        "@phosphor-icons/react": "^2.1.10",
         "@reduxjs/toolkit": "^2.12.0",
         "modern-sk": "git+https://git.ollyhearn.ru/olly/modern-sk.git",
         "react": "^19.2.6",

package.json

@@ -13,6 +13,7 @@
     "test:watch": "rstest --watch"
   },
   "dependencies": {
+    "@phosphor-icons/react": "^2.1.10",
     "@reduxjs/toolkit": "^2.12.0",
     "modern-sk": "git+https://git.ollyhearn.ru/olly/modern-sk.git",
     "react": "^19.2.6",

src/api/baseQuery.ts

@@ -1,4 +1,9 @@
-import { fetchBaseQuery, type BaseQueryFn, type FetchArgs, type FetchBaseQueryError } from '@reduxjs/toolkit/query/react';
+import {
+  fetchBaseQuery,
+  type BaseQueryFn,
+  type FetchArgs,
+  type FetchBaseQueryError,
+} from '@reduxjs/toolkit/query/react';
 import type { RootState } from '../store';
 import { getApiBaseUrl } from '../config/runtime-config';
 import { logout, setTokens } from '../store/slices/auth';
@@ -13,33 +18,49 @@ const rawBaseQuery = () =>
     },
   });
 
-export const baseQueryWithReauth: BaseQueryFn<string | FetchArgs, unknown, FetchBaseQueryError> =
+export const baseQueryWithReauth: BaseQueryFn<
-  async (args, api, extraOptions) => {
+  string | FetchArgs,
-    let result = await rawBaseQuery()(args, api, extraOptions);
+  unknown,
+  FetchBaseQueryError
+> = async (args, api, extraOptions) => {
+  let result = await rawBaseQuery()(args, api, extraOptions);
 
-    if (result.error?.status === 401) {
+  if (result.error?.status === 401) {
-      const state = api.getState() as RootState;
+    const state = api.getState() as RootState;
-      const refreshToken = state.auth.refreshToken;
+    const refreshToken = state.auth.refreshToken;
 
-      if (refreshToken) {
+    if (refreshToken) {
-        const refreshResult = await rawBaseQuery()({
+      const refreshResult = await rawBaseQuery()(
+        {
           url: '/auth/refresh',
           method: 'POST',
           body: { refreshToken },
-        }, api, extraOptions);
+        },
+        api,
+        extraOptions,
+      );
 
-        if (refreshResult.data) {
+      if (refreshResult.data) {
-          const { accessToken, refreshToken: newRefresh, expiresIn } =
+        const {
-            (refreshResult.data as { accessToken: string; refreshToken: string; expiresIn: number });
+          accessToken,
-          api.dispatch(setTokens({ accessToken, refreshToken: newRefresh, expiresIn }));
+          refreshToken: newRefresh,
-          result = await rawBaseQuery()(args, api, extraOptions);
+          expiresIn,
-        } else {
+        } = refreshResult.data as {
-          api.dispatch(logout());
+          accessToken: string;
-        }
+          refreshToken: string;
+          expiresIn: number;
+        };
+        api.dispatch(
+          setTokens({ accessToken, refreshToken: newRefresh, expiresIn }),
+        );
+        result = await rawBaseQuery()(args, api, extraOptions);
       } else {
         api.dispatch(logout());
       }
+    } else {
+      api.dispatch(logout());
     }
+  }
 
-    return result;
+  return result;
-  };
+};

src/api/endpoints/admin.ts

@@ -7,12 +7,27 @@ export const adminApi = api.injectEndpoints({
       query: () => '/admin/users',
       providesTags: ['User'],
     }),
-    createUser: build.mutation<User, { username: string; password: string; email?: string; role: 'admin' | 'user' }>({
+    createUser: build.mutation<
+      User,
+      {
+        username: string;
+        password: string;
+        email?: string;
+        role: 'admin' | 'user';
+      }
+    >({
       query: (body) => ({ url: '/admin/users', method: 'POST', body }),
       invalidatesTags: ['User'],
     }),
-    updateUser: build.mutation<User, { id: string; role?: 'admin' | 'user'; email?: string }>({
+    updateUser: build.mutation<
-      query: ({ id, ...body }) => ({ url: `/admin/users/${id}`, method: 'PATCH', body }),
+      User,
+      { id: string; role?: 'admin' | 'user'; email?: string }
+    >({
+      query: ({ id, ...body }) => ({
+        url: `/admin/users/${id}`,
+        method: 'PATCH',
+        body,
+      }),
       invalidatesTags: ['User'],
     }),
     deleteUser: build.mutation<void, string>({
@@ -23,4 +38,9 @@ export const adminApi = api.injectEndpoints({
   overrideExisting: false,
 });
 
-export const { useGetUsersQuery, useCreateUserMutation, useUpdateUserMutation, useDeleteUserMutation } = adminApi;
+export const {
+  useGetUsersQuery,
+  useCreateUserMutation,
+  useUpdateUserMutation,
+  useDeleteUserMutation,
+} = adminApi;

src/api/endpoints/auth.ts

@@ -9,7 +9,10 @@ export const authApi = api.injectEndpoints({
     logout: build.mutation<void, void>({
       query: () => ({ url: '/auth/logout', method: 'POST' }),
     }),
-    refreshToken: build.mutation<{ accessToken: string; refreshToken: string; expiresIn: number }, { refreshToken: string }>({
+    refreshToken: build.mutation<
+      { accessToken: string; refreshToken: string; expiresIn: number },
+      { refreshToken: string }
+    >({
       query: (body) => ({ url: '/auth/refresh', method: 'POST', body }),
     }),
     me: build.query<import('../types').User, void>({

src/api/endpoints/downloads.ts

@@ -3,11 +3,20 @@ import type { DownloadJob } from '../types';
 
 export const downloadsApi = api.injectEndpoints({
   endpoints: (build) => ({
-    getDownloads: build.query<DownloadJob[], { status?: DownloadJob['status'] } | void>({
+    getDownloads: build.query<
+      DownloadJob[],
+      { status?: DownloadJob['status'] } | void
+    >({
       query: (params) => ({ url: '/downloads', params: params ?? {} }),
       providesTags: ['Download'],
     }),
-    addDownload: build.mutation<DownloadJob, { url: string; metadata?: { title?: string; artist?: string; album?: string } }>({
+    addDownload: build.mutation<
+      DownloadJob,
+      {
+        url: string;
+        metadata?: { title?: string; artist?: string; album?: string };
+      }
+    >({
       query: (body) => ({ url: '/downloads', method: 'POST', body }),
       invalidatesTags: ['Download'],
     }),
@@ -23,4 +32,9 @@ export const downloadsApi = api.injectEndpoints({
   overrideExisting: false,
 });
 
-export const { useGetDownloadsQuery, useAddDownloadMutation, useCancelDownloadMutation, useRetryDownloadMutation } = downloadsApi;
+export const {
+  useGetDownloadsQuery,
+  useAddDownloadMutation,
+  useCancelDownloadMutation,
+  useRetryDownloadMutation,
+} = downloadsApi;

src/api/endpoints/library.ts

@@ -1,5 +1,11 @@
 import { api } from '../index';
-import type { Track, Album, Artist, PaginatedResponse, LibraryFilters } from '../types';
+import type {
+  Track,
+  Album,
+  Artist,
+  PaginatedResponse,
+  LibraryFilters,
+} from '../types';
 
 export const libraryApi = api.injectEndpoints({
   endpoints: (build) => ({
@@ -7,18 +13,32 @@ export const libraryApi = api.injectEndpoints({
       query: (filters) => ({ url: '/library/tracks', params: filters ?? {} }),
       providesTags: (result) =>
         result
-          ? [...result.items.map(({ id }) => ({ type: 'Track' as const, id })), 'Track']
+          ? [
+              ...result.items.map(({ id }) => ({ type: 'Track' as const, id })),
+              'Track',
+            ]
           : ['Track'],
     }),
     getTrack: build.query<Track, string>({
       query: (id) => `/library/tracks/${id}`,
       providesTags: (_r, _e, id) => [{ type: 'Track', id }],
     }),
-    getAlbums: build.query<PaginatedResponse<Album>, { search?: string; artistId?: string; page?: number; pageSize?: number } | void>({
+    getAlbums: build.query<
+      PaginatedResponse<Album>,
+      {
+        search?: string;
+        artistId?: string;
+        page?: number;
+        pageSize?: number;
+      } | void
+    >({
       query: (params) => ({ url: '/library/albums', params: params ?? {} }),
       providesTags: (result) =>
         result
-          ? [...result.items.map(({ id }) => ({ type: 'Album' as const, id })), 'Album']
+          ? [
+              ...result.items.map(({ id }) => ({ type: 'Album' as const, id })),
+              'Album',
+            ]
           : ['Album'],
     }),
     getAlbum: build.query<Album, string>({
@@ -27,13 +47,25 @@ export const libraryApi = api.injectEndpoints({
     }),
     getAlbumTracks: build.query<Track[], string>({
       query: (albumId) => `/library/albums/${albumId}/tracks`,
-      providesTags: (_r, _e, albumId) => [{ type: 'Album', id: albumId }, 'Track'],
+      providesTags: (_r, _e, albumId) => [
+        { type: 'Album', id: albumId },
+        'Track',
+      ],
     }),
-    getArtists: build.query<PaginatedResponse<Artist>, { search?: string; page?: number; pageSize?: number } | void>({
+    getArtists: build.query<
+      PaginatedResponse<Artist>,
+      { search?: string; page?: number; pageSize?: number } | void
+    >({
       query: (params) => ({ url: '/library/artists', params: params ?? {} }),
       providesTags: (result) =>
         result
-          ? [...result.items.map(({ id }) => ({ type: 'Artist' as const, id })), 'Artist']
+          ? [
+              ...result.items.map(({ id }) => ({
+                type: 'Artist' as const,
+                id,
+              })),
+              'Artist',
+            ]
           : ['Artist'],
     }),
     getArtist: build.query<Artist, string>({
@@ -42,9 +74,15 @@ export const libraryApi = api.injectEndpoints({
     }),
     getArtistAlbums: build.query<Album[], string>({
       query: (artistId) => `/library/artists/${artistId}/albums`,
-      providesTags: (_r, _e, artistId) => [{ type: 'Artist', id: artistId }, 'Album'],
+      providesTags: (_r, _e, artistId) => [
+        { type: 'Artist', id: artistId },
+        'Album',
+      ],
     }),
-    searchLibrary: build.query<{ tracks: Track[]; albums: Album[]; artists: Artist[] }, string>({
+    searchLibrary: build.query<
+      { tracks: Track[]; albums: Album[]; artists: Artist[] },
+      string
+    >({
       query: (q) => ({ url: '/library/search', params: { q } }),
       providesTags: ['Track', 'Album', 'Artist'],
     }),

src/api/endpoints/likes.ts

@@ -7,7 +7,10 @@ export const likesApi = api.injectEndpoints({
       invalidatesTags: (_r, _e, id) => ['Like', { type: 'Track', id }],
     }),
     unlikeTrack: build.mutation<void, string>({
-      query: (trackId) => ({ url: `/likes/tracks/${trackId}`, method: 'DELETE' }),
+      query: (trackId) => ({
+        url: `/likes/tracks/${trackId}`,
+        method: 'DELETE',
+      }),
       invalidatesTags: (_r, _e, id) => ['Like', { type: 'Track', id }],
     }),
   }),

src/api/endpoints/playlists.ts

@@ -15,25 +15,52 @@ export const playlistsApi = api.injectEndpoints({
       query: (id) => `/playlists/${id}/tracks`,
       providesTags: (_r, _e, id) => [{ type: 'Playlist', id }, 'Track'],
     }),
-    createPlaylist: build.mutation<Playlist, { name: string; description?: string; isPublic?: boolean }>({
+    createPlaylist: build.mutation<
+      Playlist,
+      { name: string; description?: string; isPublic?: boolean }
+    >({
       query: (body) => ({ url: '/playlists', method: 'POST', body }),
       invalidatesTags: ['Playlist'],
     }),
-    updatePlaylist: build.mutation<Playlist, { id: string; name?: string; description?: string; isPublic?: boolean }>({
+    updatePlaylist: build.mutation<
-      query: ({ id, ...body }) => ({ url: `/playlists/${id}`, method: 'PATCH', body }),
+      Playlist,
+      { id: string; name?: string; description?: string; isPublic?: boolean }
+    >({
+      query: ({ id, ...body }) => ({
+        url: `/playlists/${id}`,
+        method: 'PATCH',
+        body,
+      }),
       invalidatesTags: (_r, _e, { id }) => [{ type: 'Playlist', id }],
     }),
     deletePlaylist: build.mutation<void, string>({
       query: (id) => ({ url: `/playlists/${id}`, method: 'DELETE' }),
       invalidatesTags: ['Playlist'],
     }),
-    addTrackToPlaylist: build.mutation<void, { playlistId: string; trackId: string }>({
+    addTrackToPlaylist: build.mutation<
-      query: ({ playlistId, trackId }) => ({ url: `/playlists/${playlistId}/tracks`, method: 'POST', body: { trackId } }),
+      void,
-      invalidatesTags: (_r, _e, { playlistId }) => [{ type: 'Playlist', id: playlistId }],
+      { playlistId: string; trackId: string }
+    >({
+      query: ({ playlistId, trackId }) => ({
+        url: `/playlists/${playlistId}/tracks`,
+        method: 'POST',
+        body: { trackId },
+      }),
+      invalidatesTags: (_r, _e, { playlistId }) => [
+        { type: 'Playlist', id: playlistId },
+      ],
     }),
-    removeTrackFromPlaylist: build.mutation<void, { playlistId: string; trackId: string; position: number }>({
+    removeTrackFromPlaylist: build.mutation<
-      query: ({ playlistId, position }) => ({ url: `/playlists/${playlistId}/tracks/${position}`, method: 'DELETE' }),
+      void,
-      invalidatesTags: (_r, _e, { playlistId }) => [{ type: 'Playlist', id: playlistId }],
+      { playlistId: string; trackId: string; position: number }
+    >({
+      query: ({ playlistId, position }) => ({
+        url: `/playlists/${playlistId}/tracks/${position}`,
+        method: 'DELETE',
+      }),
+      invalidatesTags: (_r, _e, { playlistId }) => [
+        { type: 'Playlist', id: playlistId },
+      ],
     }),
   }),
   overrideExisting: false,

src/api/endpoints/storage.ts

@@ -12,11 +12,18 @@ export const storageApi = api.injectEndpoints({
       invalidatesTags: ['Storage', 'Track', 'Album', 'Artist'],
     }),
     deleteTrackFile: build.mutation<void, string>({
-      query: (trackId) => ({ url: `/storage/tracks/${trackId}`, method: 'DELETE' }),
+      query: (trackId) => ({
+        url: `/storage/tracks/${trackId}`,
+        method: 'DELETE',
+      }),
       invalidatesTags: ['Storage', { type: 'Track', id: undefined }],
     }),
   }),
   overrideExisting: false,
 });
 
-export const { useGetStorageStatsQuery, useScanStorageMutation, useDeleteTrackFileMutation } = storageApi;
+export const {
+  useGetStorageStatsQuery,
+  useScanStorageMutation,
+  useDeleteTrackFileMutation,
+} = storageApi;

src/api/endpoints/streaming.ts

@@ -7,7 +7,8 @@ export function getStreamUrl(trackId: string, token: string): string {
 
 export function getCoverUrl(artUrl: string | undefined): string | undefined {
   if (!artUrl) return undefined;
-  if (artUrl.startsWith('http://') || artUrl.startsWith('https://')) return artUrl;
+  if (artUrl.startsWith('http://') || artUrl.startsWith('https://'))
+    return artUrl;
   const base = getApiBaseUrl();
   return `${base}${artUrl}`;
 }

src/api/index.ts

@@ -4,6 +4,15 @@ import { baseQueryWithReauth } from './baseQuery';
 export const api = createApi({
   reducerPath: 'api',
   baseQuery: baseQueryWithReauth,
-  tagTypes: ['Track', 'Album', 'Artist', 'Playlist', 'Download', 'Like', 'User', 'Storage'],
+  tagTypes: [
+    'Track',
+    'Album',
+    'Artist',
+    'Playlist',
+    'Download',
+    'Like',
+    'User',
+    'Storage',
+  ],
   endpoints: () => ({}),
 });

src/components/common/ArtTile.tsx

@@ -0,0 +1,76 @@
+/*
+ * Procedural cover-art tile: a folder-colour gloss + initials, picked
+ * deterministically from a seed string. Used for dense rows (player, queue)
+ * and as a stand-in while real album art is absent (stub mode). Mirrors the
+ * design reference's ArtTile.
+ */
+
+// jewel-tone palette nodding to the Ubuntu "folder colour" idea
+const TILE_PALETTE: ReadonlyArray<readonly [string, string]> = [
+  ['#bef264', '#5a7d1e'], // lime
+  ['#e9572b', '#7a2410'], // ember
+  ['#6db3f2', '#1d4d78'], // blue
+  ['#b07bf2', '#48246e'], // purple
+  ['#e6a93c', '#7a531a'], // amber
+  ['#4fd1c5', '#155e57'], // teal
+  ['#f26db3', '#7a2452'], // pink
+];
+
+function hashHue(str: string): number {
+  let h = 0;
+  for (let i = 0; i < str.length; i++) h = (h * 31 + str.charCodeAt(i)) >>> 0;
+  return h;
+}
+
+interface Props {
+  seed: string;
+  size?: number;
+  radius?: number;
+  label?: string;
+  src?: string;
+}
+
+export function ArtTile({ seed, size = 40, radius, label, src }: Props) {
+  const r = radius ?? Math.max(4, Math.round(size * 0.16));
+
+  if (src) {
+    return (
+      <img
+        src={src}
+        alt=""
+        width={size}
+        height={size}
+        className="arttile"
+        style={{ borderRadius: r, objectFit: 'cover' }}
+      />
+    );
+  }
+
+  const [a, b] = TILE_PALETTE[hashHue(seed || 'x') % TILE_PALETTE.length];
+  const initials = (label ?? '')
+    .split(/\s+/)
+    .slice(0, 2)
+    .map((w) => w[0] ?? '')
+    .join('')
+    .toUpperCase();
+
+  return (
+    <div
+      className="arttile"
+      style={{
+        width: size,
+        height: size,
+        borderRadius: r,
+        background: `linear-gradient(150deg, ${a}, ${b})`,
+      }}
+    >
+      <span className="arttile-sheen" style={{ borderRadius: r }} />
+      <span
+        className="arttile-initials"
+        style={{ fontSize: Math.max(9, size * 0.3) }}
+      >
+        {initials}
+      </span>
+    </div>
+  );
+}

src/components/common/EmptyState.tsx

@@ -7,13 +7,35 @@ interface EmptyStateProps {
   action?: ReactNode;
 }
 
-export function EmptyState({ icon, title, description, action }: EmptyStateProps) {
+export function EmptyState({
+  icon,
+  title,
+  description,
+  action,
+}: EmptyStateProps) {
   return (
-    <div style={{ display: 'flex', flexDirection: 'column', alignItems: 'center', justifyContent: 'center', padding: '4rem 2rem', gap: '1rem', textAlign: 'center', color: 'var(--color-text-2)' }}>
+    <div
+      style={{
+        display: 'flex',
+        flexDirection: 'column',
+        alignItems: 'center',
+        justifyContent: 'center',
+        padding: '4rem 2rem',
+        gap: '1rem',
+        textAlign: 'center',
+        color: 'var(--color-text-2)',
+      }}
+    >
       {icon && <div style={{ fontSize: '2.5rem', opacity: 0.5 }}>{icon}</div>}
       <div>
-        <p style={{ margin: 0, fontWeight: 600, color: 'var(--color-text-1)' }}>{title}</p>
+        <p style={{ margin: 0, fontWeight: 600, color: 'var(--color-text-1)' }}>
-        {description && <p style={{ margin: '0.25rem 0 0', fontSize: '0.875rem' }}>{description}</p>}
+          {title}
+        </p>
+        {description && (
+          <p style={{ margin: '0.25rem 0 0', fontSize: '0.875rem' }}>
+            {description}
+          </p>
+        )}
       </div>
       {action}
     </div>

src/components/common/ErrorState.tsx

@@ -5,13 +5,21 @@ interface ErrorStateProps {
   onRetry?: () => void;
 }
 
-export function ErrorState({ message = 'Something went wrong', onRetry }: ErrorStateProps) {
+export function ErrorState({
+  message = 'Something went wrong',
+  onRetry,
+}: ErrorStateProps) {
   return (
     <div style={{ padding: '2rem' }}>
       <Callout variant="danger">
         {message}
         {onRetry && (
-          <Button variant="ghost" size="sm" onClick={onRetry} style={{ marginLeft: '1rem' }}>
+          <Button
+            variant="ghost"
+            size="sm"
+            onClick={onRetry}
+            style={{ marginLeft: '1rem' }}
+          >
             Retry
           </Button>
         )}

src/components/common/Icon.tsx

@@ -0,0 +1,101 @@
+/*
+ * Thin wrapper over @phosphor-icons/react so app code can reference icons by
+ * the kebab names used in the design reference (`<Icon name="vinyl-record" />`)
+ * instead of importing each component. modern-sk is intentionally icon-agnostic
+ * (its SearchField/MenuItem/Callout take an `icon` ReactNode), so the icon set
+ * is the app's concern.
+ *
+ * The rendered <svg> carries className "ph" and sizes to 1em, so the shell CSS
+ * controls size/colour via font-size + currentColor, exactly like the reference.
+ */
+import type { CSSProperties } from 'react';
+import {
+  ArrowCircleDown,
+  ArrowsClockwise,
+  CheckCircle,
+  Cloud,
+  DotsSixVertical,
+  GearSix,
+  HardDrives,
+  Heart,
+  House,
+  MagnifyingGlass,
+  Pause,
+  Play,
+  Playlist,
+  Plus,
+  PushPin,
+  Queue,
+  Radio,
+  Repeat,
+  ShieldCheck,
+  Shuffle,
+  SignOut,
+  SkipBack,
+  SkipForward,
+  Sparkle,
+  SpeakerHigh,
+  SpeakerSimpleX,
+  ThumbsDown,
+  Trash,
+  UploadSimple,
+  VinylRecord,
+  WarningCircle,
+  X,
+  type IconProps,
+} from '@phosphor-icons/react';
+
+const ICONS = {
+  'vinyl-record': VinylRecord,
+  house: House,
+  'magnifying-glass': MagnifyingGlass,
+  'arrow-circle-down': ArrowCircleDown,
+  'upload-simple': UploadSimple,
+  'hard-drives': HardDrives,
+  'push-pin': PushPin,
+  playlist: Playlist,
+  plus: Plus,
+  'shield-check': ShieldCheck,
+  'gear-six': GearSix,
+  queue: Queue,
+  trash: Trash,
+  x: X,
+  radio: Radio,
+  sparkle: Sparkle,
+  'dots-six-vertical': DotsSixVertical,
+  shuffle: Shuffle,
+  'skip-back': SkipBack,
+  play: Play,
+  pause: Pause,
+  'skip-forward': SkipForward,
+  repeat: Repeat,
+  heart: Heart,
+  'thumbs-down': ThumbsDown,
+  'speaker-high': SpeakerHigh,
+  'speaker-x': SpeakerSimpleX,
+  cloud: Cloud,
+  'check-circle': CheckCircle,
+  'warning-circle': WarningCircle,
+  'sign-out': SignOut,
+  'arrows-clockwise': ArrowsClockwise,
+} satisfies Record<string, React.ComponentType<IconProps>>;
+
+export type IconName = keyof typeof ICONS;
+
+interface Props {
+  name: IconName;
+  fill?: boolean;
+  style?: CSSProperties;
+  className?: string;
+}
+
+export function Icon({ name, fill, style, className }: Props) {
+  const Cmp = ICONS[name];
+  return (
+    <Cmp
+      weight={fill ? 'fill' : 'regular'}
+      className={className ? `ph ${className}` : 'ph'}
+      style={{ flexShrink: 0, ...style }}
+    />
+  );
+}

src/components/layout/AppShell.tsx

@@ -5,17 +5,24 @@ import { QueuePanel } from '../player/QueuePanel';
 
 export function AppShell() {
   return (
-    <div style={{ display: 'flex', flexDirection: 'column', height: '100vh', overflow: 'hidden' }}>
+    <div
-      <div style={{ display: 'flex', flex: 1, overflow: 'hidden' }}>
+      style={{
+        display: 'flex',
+        flexDirection: 'column',
+        height: '100vh',
+        overflow: 'hidden',
+      }}
+    >
+      <div className="app-body">
         <Sidebar />
-        <main style={{ flex: 1, overflow: 'auto', display: 'flex', flexDirection: 'column' }}>
+        <main className="app-main">
-          <Outlet />
+          <div className="app-screen">
+            <Outlet />
+          </div>
         </main>
         <QueuePanel />
       </div>
-      <div style={{ position: 'relative', flexShrink: 0 }}>
+      <PersistentPlayer />
-        <PersistentPlayer />
-      </div>
     </div>
   );
 }

src/components/layout/Sidebar.tsx

@@ -1,113 +1,147 @@
-import { Badge } from 'modern-sk';
 import { NavLink, useNavigate } from 'react-router';
-import { ConnectionStatus } from '../common/ConnectionStatus';
+import { Icon, type IconName } from '../common/Icon';
-import { useAppSelector, useAppDispatch } from '../../hooks/useAppDispatch';
+import { useAppDispatch } from '../../hooks/useAppDispatch';
 import { usePermissions } from '../../hooks/usePermissions';
+import { useConnectionStatus } from '../../hooks/useConnectionStatus';
 import { logout } from '../../store/slices/auth';
+import { useGetPlaylistsQuery } from '../../api/endpoints/playlists';
+import { getActiveInstance } from '../../config/instances';
 
-const NAV_ITEMS = [
+interface NavDef {
-  { to: '/', label: 'Home', icon: '⌂' },
+  to: string;
-  { to: '/library', label: 'Library', icon: '♫' },
+  label: string;
-  { to: '/search', label: 'Search & Download', icon: '⊕' },
+  icon: IconName;
-  { to: '/downloads', label: 'Downloads', icon: '↓' },
+  end?: boolean;
-  { to: '/storage', label: 'Storage', icon: '⊞' },
+}
-  { to: '/settings', label: 'Settings', icon: '⚙' },
-] as const;
 
-const ADMIN_ITEMS = [
+const MAIN_NAV: NavDef[] = [
-  { to: '/admin', label: 'Admin', icon: '🔑' },
+  { to: '/', label: 'Home', icon: 'house', end: true },
-] as const;
+  { to: '/library', label: 'Library', icon: 'vinyl-record' },
+  { to: '/search', label: 'Search & download', icon: 'magnifying-glass' },
+  { to: '/downloads', label: 'Downloads', icon: 'arrow-circle-down' },
+  { to: '/storage', label: 'Storage', icon: 'hard-drives' },
+];
+
+const CONN_CLASS: Record<string, { cls: string; txt: string }> = {
+  connected: { cls: 'online', txt: 'Connected' },
+  connecting: { cls: 'syncing', txt: 'Connecting…' },
+  disconnected: { cls: 'offline', txt: 'Offline' },
+  error: { cls: 'error', txt: 'Unreachable' },
+};
+
+function navClass({ isActive }: { isActive: boolean }) {
+  return isActive ? 'nav-item active' : 'nav-item';
+}
 
 export function Sidebar() {
   const dispatch = useAppDispatch();
   const navigate = useNavigate();
   const { user, isAdmin } = usePermissions();
-  const collapsed = useAppSelector((s) => s.ui.sidebarCollapsed);
+  const status = useConnectionStatus();
+  const { data: playlists } = useGetPlaylistsQuery();
+  const instance = getActiveInstance();
 
-  const handleLogout = () => {
+  const conn = CONN_CLASS[status] ?? CONN_CLASS.connecting;
+  const online = status === 'connected';
+
+  const handleLogout = (e: React.MouseEvent) => {
+    e.stopPropagation();
     dispatch(logout());
     void navigate('/connect');
   };
 
   return (
-    <nav style={{ width: collapsed ? '3.5rem' : '14rem', flexShrink: 0, borderRight: '1px solid var(--color-border)', display: 'flex', flexDirection: 'column', padding: '0.75rem 0', background: 'var(--color-surface-1)', transition: 'width 0.2s', overflow: 'hidden' }}>
+    <aside className="sidebar">
-      <div style={{ padding: collapsed ? '0 0.5rem' : '0 0.75rem', marginBottom: '1.5rem' }}>
+      <div className="sb-scroll">
-        <span style={{ fontWeight: 700, fontSize: '1.125rem', color: 'var(--color-accent)', whiteSpace: 'nowrap' }}>
+        <div className="sb-brand">
-          {collapsed ? '♫' : '♫ MCMA'}
+          <Icon name="vinyl-record" fill />
-        </span>
+          <span>{instance?.name ?? 'MCMA'}</span>
-      </div>
+        </div>
 
-      <div style={{ flex: 1, display: 'flex', flexDirection: 'column', gap: '2px' }}>
+        <div className="sb-sec">
-        {NAV_ITEMS.map(({ to, label, icon }) => (
+          {MAIN_NAV.map(({ to, label, icon, end }) => (
-          <NavLink
+            <NavLink key={to} to={to} end={end} className={navClass}>
-            key={to}
+              <Icon name={icon} />
-            to={to}
+              <span>{label}</span>
-            end={to === '/'}
+            </NavLink>
-            style={({ isActive }) => ({
+          ))}
-              display: 'flex',
+        </div>
-              alignItems: 'center',
+
-              gap: '0.75rem',
+        <div className="sb-sec">
-              padding: collapsed ? '0.625rem 0.75rem' : '0.625rem 1rem',
+          <span className="msk-label">Playlists</span>
-              borderRadius: 6,
+          {(playlists?.items ?? []).map((pl) => (
-              margin: '0 0.375rem',
+            <NavLink
-              color: isActive ? 'var(--color-accent)' : 'var(--color-text-2)',
+              key={pl.id}
-              background: isActive ? 'var(--color-surface-2)' : undefined,
+              to={`/library/playlists/${pl.id}`}
-              fontWeight: isActive ? 600 : 400,
+              className={navClass}
-              textDecoration: 'none',
+            >
-              fontSize: '0.875rem',
+              <Icon name="playlist" />
-              whiteSpace: 'nowrap',
+              <span className="pl-name">{pl.name}</span>
-              transition: 'background 0.1s, color 0.1s',
+            </NavLink>
-            })}
+          ))}
+          <button
+            type="button"
+            className="pl-item"
+            onClick={() => void navigate('/library')}
           >
-            <span style={{ flexShrink: 0, fontSize: '1rem' }}>{icon}</span>
+            <Icon name="plus" />
-            {!collapsed && label}
+            <span className="pl-name">New playlist</span>
-          </NavLink>
+          </button>
-        ))}
+        </div>
 
-        {isAdmin && (
+        {isAdmin ? (
-          <>
+          <div className="sb-sec">
-            <div style={{ height: 1, background: 'var(--color-border)', margin: '0.5rem 0.75rem' }} />
+            <span className="msk-label">Administration</span>
-            {ADMIN_ITEMS.map(({ to, label, icon }) => (
+            <NavLink to="/admin" className={navClass}>
-              <NavLink
+              <Icon name="shield-check" />
-                key={to}
+              <span>Admin</span>
-                to={to}
+            </NavLink>
-                style={({ isActive }) => ({
+            <NavLink to="/settings" className={navClass}>
-                  display: 'flex',
+              <Icon name="gear-six" />
-                  alignItems: 'center',
+              <span>Settings</span>
-                  gap: '0.75rem',
+            </NavLink>
-                  padding: collapsed ? '0.625rem 0.75rem' : '0.625rem 1rem',
+          </div>
-                  borderRadius: 6,
+        ) : (
-                  margin: '0 0.375rem',
+          <div className="sb-sec">
-                  color: isActive ? 'var(--color-accent)' : 'var(--color-text-2)',
+            <NavLink to="/settings" className={navClass}>
-                  background: isActive ? 'var(--color-surface-2)' : undefined,
+              <Icon name="gear-six" />
-                  fontWeight: isActive ? 600 : 400,
+              <span>Settings</span>
-                  textDecoration: 'none',
+            </NavLink>
-                  fontSize: '0.875rem',
-                  whiteSpace: 'nowrap',
-                })}
-              >
-                <span style={{ flexShrink: 0 }}>{icon}</span>
-                {!collapsed && label}
-              </NavLink>
-            ))}
-          </>
-        )}
-      </div>
-
-      <div style={{ padding: collapsed ? '0 0.5rem' : '0 0.75rem', display: 'flex', flexDirection: 'column', gap: '0.5rem' }}>
-        {!collapsed && <ConnectionStatus />}
-        {!collapsed && user && (
-          <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', padding: '0.5rem 0.25rem' }}>
-            <div>
-              <div style={{ fontSize: '0.8125rem', fontWeight: 600, color: 'var(--color-text-1)' }}>{user.username}</div>
-              <Badge variant={user.role === 'admin' ? 'lime' : 'neutral'} style={{ marginTop: 2 }}>{user.role}</Badge>
-            </div>
-            <button onClick={handleLogout} style={{ background: 'none', border: 'none', cursor: 'pointer', color: 'var(--color-text-3)', fontSize: '0.75rem', padding: '0.25rem' }}>
-              Sign out
-            </button>
           </div>
         )}
       </div>
-    </nav>
+
+      <div className="sb-foot">
+        <button
+          type="button"
+          className={`conn ${conn.cls}`}
+          onClick={() => void navigate('/connect')}
+          title="Connection — manage instances"
+        >
+          <span className="led" />
+          {conn.txt}
+        </button>
+        {user && (
+          <button
+            type="button"
+            className="user-chip"
+            onClick={() => void navigate('/settings')}
+          >
+            <div className="user-av">
+              {user.username.charAt(0).toUpperCase()}
+            </div>
+            <div className="user-meta">
+              <div className="nm">{user.username}</div>
+              <div className="rl">
+                {user.role} · {online ? 'online' : 'offline'}
+              </div>
+            </div>
+            <span className="uc-action" onClick={handleLogout} title="Sign out">
+              <Icon name="sign-out" />
+            </span>
+          </button>
+        )}
+      </div>
+    </aside>
   );
 }

src/components/player/PersistentPlayer.tsx

@@ -1,6 +1,17 @@
-import { IconButton, Slider, Tooltip } from 'modern-sk';
+import { Slider } from 'modern-sk';
+import { Icon } from '../common/Icon';
+import { ArtTile } from '../common/ArtTile';
 import { useAppDispatch, useAppSelector } from '../../hooks/useAppDispatch';
-import { pause, resume, toggleMute, setVolume, toggleNowPlaying, toggleQueue } from '../../store/slices/player';
+import {
+  pause,
+  resume,
+  toggleMute,
+  setVolume,
+  toggleShuffle,
+  setRepeat,
+  toggleNowPlaying,
+  toggleQueue,
+} from '../../store/slices/player';
 import { useAudioPlayer } from '../../hooks/useAudioPlayer';
 import { formatDuration } from '../../lib/format';
 import { getCoverUrl } from '../../api/endpoints/streaming';
@@ -13,94 +24,140 @@ export function PersistentPlayer() {
   const currentEntry = queue.entries[queue.currentIndex];
 
   if (!currentEntry && !player.currentTrackId) {
-    return (
+    return <div className="player empty">Nothing playing</div>;
-      <div style={{ height: '4rem', borderTop: '1px solid var(--color-border)', display: 'flex', alignItems: 'center', justifyContent: 'center', padding: '0 1.5rem', color: 'var(--color-text-3)', fontSize: '0.875rem' }}>
-        Nothing playing
-      </div>
-    );
   }
 
-  const artUrl = currentEntry?.albumArtUrl ? getCoverUrl(currentEntry.albumArtUrl) : undefined;
+  const artUrl = getCoverUrl(currentEntry?.albumArtUrl);
-  const progressPercent = player.duration > 0 ? (player.position / player.duration) * 100 : 0;
+  const seedLabel = currentEntry?.albumTitle ?? currentEntry?.title ?? '';
+  // Streaming is the web default; local playback is a mobile-client concern.
+  const onStream = true;
 
   return (
-    <div style={{ height: '4rem', borderTop: '1px solid var(--color-border)', display: 'grid', gridTemplateColumns: '1fr auto 1fr', alignItems: 'center', padding: '0 1rem', gap: '1rem', background: 'var(--color-surface-1)' }}>
+    <div className="player">
-      {/* track info */}
+      {/* now-playing identity */}
       <div
-        style={{ display: 'flex', alignItems: 'center', gap: '0.75rem', minWidth: 0, cursor: 'pointer' }}
+        className="pl-now"
         onClick={() => dispatch(toggleNowPlaying())}
+        style={{ cursor: 'pointer' }}
       >
-        {artUrl ? (
+        <ArtTile seed={seedLabel} size={54} label={seedLabel} src={artUrl} />
-          <img src={artUrl} alt="" width={40} height={40} style={{ borderRadius: 4, objectFit: 'cover', flexShrink: 0 }} />
+        <div className="pl-now-tt">
-        ) : (
+          <div className="t">{currentEntry?.title ?? '—'}</div>
-          <div style={{ width: 40, height: 40, borderRadius: 4, background: 'var(--color-surface-3)', flexShrink: 0 }} />
+          <div className="a">{currentEntry?.artistName ?? ''}</div>
-        )}
+          <div
-        <div style={{ minWidth: 0 }}>
+            className="pl-srcbadge"
-          <div style={{ fontWeight: 500, overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap', fontSize: '0.875rem' }}>
+            style={{ color: onStream ? 'var(--fg-3)' : 'var(--lime)' }}
-            {currentEntry?.title ?? '—'}
+          >
-          </div>
+            <Icon name={onStream ? 'cloud' : 'check-circle'} fill={!onStream} />
-          <div style={{ fontSize: '0.75rem', color: 'var(--color-text-2)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
+            {onStream ? 'Streaming · 320 kbps' : 'Local · FLAC'}
-            {currentEntry?.artistName ?? ''}
           </div>
         </div>
       </div>
 
-      {/* controls + scrubber */}
+      {/* transport + scrubber */}
-      <div style={{ display: 'flex', flexDirection: 'column', alignItems: 'center', gap: '0.25rem', minWidth: '20rem' }}>
+      <div className="pl-center">
-        <div style={{ display: 'flex', alignItems: 'center', gap: '0.5rem' }}>
+        <div className="pl-transport">
-          <IconButton variant="ghost" size="sm" onClick={playPrev} aria-label="Previous">⏮</IconButton>
+          <button
-          <IconButton
+            type="button"
-            variant="primary"
+            className={`pl-tbtn${player.shuffle ? ' on' : ''}`}
-            onClick={() => player.isPlaying ? dispatch(pause()) : dispatch(resume())}
+            onClick={() => dispatch(toggleShuffle())}
-            aria-label={player.isPlaying ? 'Pause' : 'Play'}
+            title="Shuffle"
           >
-            {player.isPlaying ? '⏸' : '▶'}
+            <Icon name="shuffle" />
-          </IconButton>
+          </button>
-          <IconButton variant="ghost" size="sm" onClick={playNext} aria-label="Next">⏭</IconButton>
+          <button
+            type="button"
+            className="pl-tbtn"
+            onClick={playPrev}
+            title="Previous"
+          >
+            <Icon name="skip-back" fill />
+          </button>
+          <button
+            type="button"
+            className="pl-play"
+            onClick={() =>
+              player.isPlaying ? dispatch(pause()) : dispatch(resume())
+            }
+            title={player.isPlaying ? 'Pause' : 'Play'}
+          >
+            <Icon name={player.isPlaying ? 'pause' : 'play'} fill />
+          </button>
+          <button
+            type="button"
+            className="pl-tbtn"
+            onClick={playNext}
+            title="Next"
+          >
+            <Icon name="skip-forward" fill />
+          </button>
+          <button
+            type="button"
+            className={`pl-tbtn${player.repeat !== 'none' ? ' on' : ''}`}
+            onClick={() =>
+              dispatch(
+                setRepeat(
+                  player.repeat === 'none'
+                    ? 'all'
+                    : player.repeat === 'all'
+                      ? 'one'
+                      : 'none',
+                ),
+              )
+            }
+            title={`Repeat: ${player.repeat}`}
+          >
+            <Icon name="repeat" />
+          </button>
         </div>
-        <div style={{ display: 'flex', alignItems: 'center', gap: '0.5rem', width: '100%' }}>
+        <div className="pl-seek">
-          <span style={{ fontSize: '0.7rem', color: 'var(--color-text-3)', minWidth: '2.5rem', textAlign: 'right' }}>
+          <span className="pl-time">
             {formatDuration(player.position * 1000)}
           </span>
           <Slider
+            className="pl-seek-slider"
             min={0}
             max={player.duration || 1}
             step={1}
             value={[player.position]}
             onValueChange={([v]) => seek(v)}
-            style={{ flex: 1 }}
+            aria-label="Seek"
           />
-          <span style={{ fontSize: '0.7rem', color: 'var(--color-text-3)', minWidth: '2.5rem' }}>
+          <span className="pl-time">
             {formatDuration(player.duration * 1000)}
           </span>
         </div>
       </div>
 
       {/* volume + queue */}
-      <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'flex-end', gap: '0.5rem' }}>
+      <div className="pl-right">
-        <Tooltip content={player.muted ? 'Unmute' : 'Mute'}>
+        <button
-          <IconButton variant="ghost" size="sm" onClick={() => dispatch(toggleMute())} aria-label="Toggle mute">
+          type="button"
-            {player.muted ? '🔇' : '🔊'}
+          className="pl-tbtn"
-          </IconButton>
+          onClick={() => dispatch(toggleMute())}
-        </Tooltip>
+          title={player.muted ? 'Unmute' : 'Mute'}
-        <Slider
+        >
-          min={0}
+          <Icon name={player.muted ? 'speaker-x' : 'speaker-high'} />
-          max={1}
+        </button>
-          step={0.01}
+        <div className="pl-vol">
-          value={[player.muted ? 0 : player.volume]}
+          <Slider
-          onValueChange={([v]) => dispatch(setVolume(v))}
+            className="pl-vol-slider"
-          style={{ width: '6rem' }}
+            min={0}
-        />
+            max={1}
-        <Tooltip content="Queue">
+            step={0.01}
-          <IconButton variant={player.isQueueOpen ? 'primary' : 'ghost'} size="sm" onClick={() => dispatch(toggleQueue())} aria-label="Toggle queue">
+            value={[player.muted ? 0 : player.volume]}
-            ≡
+            onValueChange={([v]) => dispatch(setVolume(v))}
-          </IconButton>
+            aria-label="Volume"
-        </Tooltip>
+          />
-      </div>
+        </div>
-
+        <button
-      {/* progress bar at bottom */}
+          type="button"
-      <div style={{ position: 'absolute', bottom: 0, left: 0, right: 0, height: 2, background: 'var(--color-surface-3)' }}>
+          className={`iconbtn sm${player.isQueueOpen ? ' on' : ''}`}
-        <div style={{ width: `${progressPercent}%`, height: '100%', background: 'var(--color-accent)', transition: 'width 0.5s linear' }} />
+          onClick={() => dispatch(toggleQueue())}
+          title="Play queue"
+        >
+          <Icon name="queue" />
+        </button>
       </div>
     </div>
   );

src/components/player/QueuePanel.tsx

@@ -1,60 +1,169 @@
-import { ScrollArea, IconButton, Badge } from 'modern-sk';
+import { Slider, Badge } from 'modern-sk';
+import { Icon } from '../common/Icon';
+import { ArtTile } from '../common/ArtTile';
 import { useAppDispatch, useAppSelector } from '../../hooks/useAppDispatch';
-import { goToIndex, removeFromQueue, clearQueue } from '../../store/slices/queue';
+import {
+  goToIndex,
+  removeFromQueue,
+  clearQueue,
+} from '../../store/slices/queue';
 import { toggleQueue } from '../../store/slices/player';
-import { formatDuration } from '../../lib/format';
 
 export function QueuePanel() {
   const dispatch = useAppDispatch();
   const queue = useAppSelector((s) => s.queue);
   const isOpen = useAppSelector((s) => s.player.isQueueOpen);
 
-  if (!isOpen) return null;
+  const now =
+    queue.currentIndex >= 0 ? queue.entries[queue.currentIndex] : undefined;
+  const upNext = queue.entries
+    .map((entry, index) => ({ entry, index }))
+    .filter(({ index }) => index > queue.currentIndex);
+  const isRadio = queue.source === 'radio';
+  const sourceLabel = queue.sourceName ?? queue.source;
 
   return (
-    <div style={{ width: '20rem', borderLeft: '1px solid var(--color-border)', display: 'flex', flexDirection: 'column', background: 'var(--color-surface-1)', flexShrink: 0 }}>
+    <aside className={`qd${isOpen ? '' : ' closed'}`} aria-hidden={!isOpen}>
-      <div style={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', padding: '0.75rem 1rem', borderBottom: '1px solid var(--color-border)' }}>
+      <div className="qd-inner">
-        <span style={{ fontWeight: 600, fontSize: '0.875rem' }}>Queue</span>
+        <div className="qd-head">
-        <div style={{ display: 'flex', gap: '0.25rem' }}>
+          <div className="row">
-          {queue.sourceName && <Badge variant="neutral">{queue.sourceName}</Badge>}
+            <h3>Play queue</h3>
-          <IconButton variant="ghost" size="sm" onClick={() => dispatch(clearQueue())} aria-label="Clear queue">✕</IconButton>
+            <div style={{ flex: 1 }} />
-          <IconButton variant="ghost" size="sm" onClick={() => dispatch(toggleQueue())} aria-label="Close">✕</IconButton>
+            <button
+              type="button"
+              className="iconbtn sm"
+              onClick={() => dispatch(clearQueue())}
+              title="Clear queue"
+            >
+              <Icon name="trash" />
+            </button>
+            <button
+              type="button"
+              className="iconbtn sm"
+              onClick={() => dispatch(toggleQueue())}
+              title="Close"
+            >
+              <Icon name="x" />
+            </button>
+          </div>
+          <div className="qd-src">
+            <Icon
+              name={isRadio ? 'radio' : 'playlist'}
+              style={{ color: isRadio ? 'var(--lime)' : 'var(--fg-3)' }}
+            />
+            {isRadio ? (
+              <span style={{ color: 'var(--lime)' }}>
+                Radio · {sourceLabel}
+              </span>
+            ) : (
+              <span>From {sourceLabel}</span>
+            )}
+          </div>
+        </div>
+
+        <div className="qd-scroll">
+          {now ? (
+            <>
+              <span
+                className="msk-label"
+                style={{ display: 'block', marginBottom: 8 }}
+              >
+                Now playing
+              </span>
+              <div className="qd-now">
+                <ArtTile
+                  seed={now.albumTitle}
+                  size={44}
+                  label={now.albumTitle}
+                />
+                <div className="qt">
+                  <div className="t">{now.title}</div>
+                  <div className="r">{now.artistName}</div>
+                </div>
+                <Icon name="cloud" style={{ color: 'var(--fg-3)' }} />
+              </div>
+
+              {isRadio && (
+                <div className="qd-radio">
+                  <div className="row">
+                    <Icon name="radio" />
+                    <span
+                      style={{
+                        fontSize: 13,
+                        fontWeight: 600,
+                        color: 'var(--fg-1)',
+                      }}
+                    >
+                      Radio active
+                    </span>
+                    <div style={{ flex: 1 }} />
+                    <Badge variant="neutral">∞ mixing</Badge>
+                  </div>
+                  {/* exploration balance — stub under the future ML contract */}
+                  <div className="expl">
+                    <span className="lab">Familiar</span>
+                    <Slider
+                      className="expl-slider"
+                      min={0}
+                      max={100}
+                      step={1}
+                      defaultValue={[42]}
+                      aria-label="Exploration"
+                    />
+                    <span className="lab">New</span>
+                  </div>
+                </div>
+              )}
+
+              <span
+                className="msk-label"
+                style={{ display: 'block', margin: '4px 0 8px' }}
+              >
+                Next up
+              </span>
+              {upNext.length === 0 ? (
+                <div className="qd-empty">Nothing queued next</div>
+              ) : (
+                upNext.map(({ entry, index }) => (
+                  <div
+                    key={`${entry.trackId}-${index}`}
+                    className="qrow"
+                    onDoubleClick={() => dispatch(goToIndex(index))}
+                    title="Double-click to play"
+                  >
+                    <span className="grip">
+                      <Icon name="dots-six-vertical" />
+                    </span>
+                    <ArtTile
+                      seed={entry.albumTitle}
+                      size={36}
+                      label={entry.albumTitle}
+                    />
+                    <div className="qt">
+                      <div className="t">{entry.title}</div>
+                      <div className="r">{entry.artistName}</div>
+                    </div>
+                    <button
+                      type="button"
+                      className="iconbtn sm"
+                      onClick={() => dispatch(removeFromQueue(index))}
+                      title="Remove from queue"
+                    >
+                      <Icon name="x" />
+                    </button>
+                  </div>
+                ))
+              )}
+
+              {isRadio && (
+                <div className="qd-loadmore">Loading more from radio…</div>
+              )}
+            </>
+          ) : (
+            <div className="qd-empty">Queue is empty</div>
+          )}
         </div>
       </div>
-      <ScrollArea style={{ flex: 1 }}>
+    </aside>
-        {queue.entries.length === 0 ? (
-          <p style={{ padding: '2rem', textAlign: 'center', color: 'var(--color-text-3)', fontSize: '0.875rem' }}>Queue is empty</p>
-        ) : (
-          queue.entries.map((entry, i) => (
-            <div
-              key={`${entry.trackId}-${i}`}
-              onDoubleClick={() => dispatch(goToIndex(i))}
-              style={{
-                display: 'grid',
-                gridTemplateColumns: '1fr auto',
-                padding: '0.5rem 1rem',
-                gap: '0.5rem',
-                alignItems: 'center',
-                background: i === queue.currentIndex ? 'var(--color-surface-2)' : undefined,
-                cursor: 'default',
-              }}
-            >
-              <div style={{ minWidth: 0 }}>
-                <div style={{ fontSize: '0.8125rem', fontWeight: i === queue.currentIndex ? 600 : 400, overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap', color: i === queue.currentIndex ? 'var(--color-accent)' : 'var(--color-text-1)' }}>
-                  {entry.title}
-                </div>
-                <div style={{ fontSize: '0.75rem', color: 'var(--color-text-3)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
-                  {entry.artistName}
-                </div>
-              </div>
-              <div style={{ display: 'flex', alignItems: 'center', gap: '0.25rem', flexShrink: 0 }}>
-                <span style={{ fontSize: '0.75rem', color: 'var(--color-text-3)' }}>{formatDuration(entry.durationMs)}</span>
-                <IconButton variant="ghost" size="sm" onClick={() => dispatch(removeFromQueue(i))} aria-label="Remove from queue">✕</IconButton>
-              </div>
-            </div>
-          ))
-        )}
-      </ScrollArea>
-    </div>
   );
 }

src/components/track/AvailabilityBadge.tsx

@@ -5,18 +5,39 @@ interface Props {
   availability: TrackAvailability;
 }
 
-const CONFIG: Record<TrackAvailability, { label: string; variant: 'lime' | 'ember' | 'neutral' | 'outline'; tooltip: string }> = {
+const CONFIG: Record<
-  server: { label: 'On server', variant: 'lime', tooltip: 'File available on server' },
+  TrackAvailability,
-  downloading: { label: 'Downloading', variant: 'neutral', tooltip: 'Currently downloading' },
+  {
+    label: string;
+    variant: 'lime' | 'ember' | 'neutral' | 'outline';
+    tooltip: string;
+  }
+> = {
+  server: {
+    label: 'On server',
+    variant: 'lime',
+    tooltip: 'File available on server',
+  },
+  downloading: {
+    label: 'Downloading',
+    variant: 'neutral',
+    tooltip: 'Currently downloading',
+  },
   error: { label: 'Error', variant: 'ember', tooltip: 'Download failed' },
-  missing: { label: 'Missing', variant: 'outline', tooltip: 'File not found on server' },
+  missing: {
+    label: 'Missing',
+    variant: 'outline',
+    tooltip: 'File not found on server',
+  },
 };
 
 export function AvailabilityBadge({ availability }: Props) {
   const cfg = CONFIG[availability];
   return (
     <Tooltip content={cfg.tooltip}>
-      <Badge variant={cfg.variant} dot>{cfg.label}</Badge>
+      <Badge variant={cfg.variant} dot>
+        {cfg.label}
+      </Badge>
     </Tooltip>
   );
 }

src/components/track/TrackContextMenu.tsx

@@ -1,4 +1,11 @@
-import { Menu, MenuTrigger, MenuContent, MenuItem, MenuSeparator, IconButton } from 'modern-sk';
+import {
+  Menu,
+  MenuTrigger,
+  MenuContent,
+  MenuItem,
+  MenuSeparator,
+  IconButton,
+} from 'modern-sk';
 import { useAppDispatch } from '../../hooks/useAppDispatch';
 import { addToQueue, addNextInQueue } from '../../store/slices/queue';
 import { play } from '../../store/slices/player';
@@ -12,7 +19,13 @@ interface Props {
   onDownload?: (track: Track) => void;
 }
 
-export function TrackContextMenu({ track, onAddToPlaylist, onEditMetadata, onDelete, onDownload }: Props) {
+export function TrackContextMenu({
+  track,
+  onAddToPlaylist,
+  onEditMetadata,
+  onDelete,
+  onDownload,
+}: Props) {
   const dispatch = useAppDispatch();
 
   const entry = {
@@ -27,18 +40,50 @@ export function TrackContextMenu({ track, onAddToPlaylist, onEditMetadata, onDel
   return (
     <Menu>
       <MenuTrigger asChild>
-        <IconButton variant="ghost" size="sm" aria-label="Track options">⋯</IconButton>
+        <IconButton variant="ghost" size="sm" aria-label="Track options">
+          ⋯
+        </IconButton>
       </MenuTrigger>
       <MenuContent>
-        <MenuItem onSelect={() => { dispatch(play(track.id)); }}>Play now</MenuItem>
+        <MenuItem
-        <MenuItem onSelect={() => { dispatch(addNextInQueue(entry)); }}>Play next</MenuItem>
+          onSelect={() => {
-        <MenuItem onSelect={() => { dispatch(addToQueue(entry)); }}>Add to queue</MenuItem>
+            dispatch(play(track.id));
+          }}
+        >
+          Play now
+        </MenuItem>
+        <MenuItem
+          onSelect={() => {
+            dispatch(addNextInQueue(entry));
+          }}
+        >
+          Play next
+        </MenuItem>
+        <MenuItem
+          onSelect={() => {
+            dispatch(addToQueue(entry));
+          }}
+        >
+          Add to queue
+        </MenuItem>
         <MenuSeparator />
-        {onAddToPlaylist && <MenuItem onSelect={() => onAddToPlaylist(track)}>Add to playlist…</MenuItem>}
+        {onAddToPlaylist && (
+          <MenuItem onSelect={() => onAddToPlaylist(track)}>
+            Add to playlist…
+          </MenuItem>
+        )}
         <MenuSeparator />
-        {onEditMetadata && <MenuItem onSelect={() => onEditMetadata(track)}>Edit metadata</MenuItem>}
+        {onEditMetadata && (
-        {onDownload && <MenuItem onSelect={() => onDownload(track)}>Download</MenuItem>}
+          <MenuItem onSelect={() => onEditMetadata(track)}>
-        {onDelete && <MenuItem onSelect={() => onDelete(track)}>Delete</MenuItem>}
+            Edit metadata
+          </MenuItem>
+        )}
+        {onDownload && (
+          <MenuItem onSelect={() => onDownload(track)}>Download</MenuItem>
+        )}
+        {onDelete && (
+          <MenuItem onSelect={() => onDelete(track)}>Delete</MenuItem>
+        )}
       </MenuContent>
     </Menu>
   );

src/components/track/TrackRow.tsx

@@ -16,7 +16,14 @@ interface Props {
   onDelete?: (track: Track) => void;
 }
 
-export function TrackRow({ track, index, showAlbum = false, onAddToPlaylist, onEditMetadata, onDelete }: Props) {
+export function TrackRow({
+  track,
+  index,
+  showAlbum = false,
+  onAddToPlaylist,
+  onEditMetadata,
+  onDelete,
+}: Props) {
   const dispatch = useAppDispatch();
   const currentTrackId = useAppSelector((s) => s.player.currentTrackId);
   const isPlaying = useAppSelector((s) => s.player.isPlaying);
@@ -27,27 +34,77 @@ export function TrackRow({ track, index, showAlbum = false, onAddToPlaylist, onE
     <Row
       selected={isActive}
       onDoubleClick={() => dispatch(play(track.id))}
-      style={{ display: 'grid', gridTemplateColumns: '2rem 2.5rem 1fr auto auto', gap: '0.75rem', alignItems: 'center', padding: '0.375rem 0.75rem', cursor: 'default' }}
+      style={{
+        display: 'grid',
+        gridTemplateColumns: '2rem 2.5rem 1fr auto auto',
+        gap: '0.75rem',
+        alignItems: 'center',
+        padding: '0.375rem 0.75rem',
+        cursor: 'default',
+      }}
     >
-      <span style={{ fontSize: '0.75rem', color: 'var(--color-text-3)', textAlign: 'right' }}>
+      <span
-        {isActive && isPlaying ? '▶' : (index !== undefined ? index + 1 : '')}
+        style={{
+          fontSize: '0.75rem',
+          color: 'var(--color-text-3)',
+          textAlign: 'right',
+        }}
+      >
+        {isActive && isPlaying ? '▶' : index !== undefined ? index + 1 : ''}
       </span>
       {artUrl ? (
-        <img src={artUrl} alt="" width={36} height={36} style={{ borderRadius: 4, objectFit: 'cover' }} />
+        <img
+          src={artUrl}
+          alt=""
+          width={36}
+          height={36}
+          style={{ borderRadius: 4, objectFit: 'cover' }}
+        />
       ) : (
-        <div style={{ width: 36, height: 36, borderRadius: 4, background: 'var(--color-surface-3)' }} />
+        <div
+          style={{
+            width: 36,
+            height: 36,
+            borderRadius: 4,
+            background: 'var(--color-surface-3)',
+          }}
+        />
       )}
       <div style={{ minWidth: 0 }}>
-        <div style={{ fontWeight: isActive ? 600 : 400, color: isActive ? 'var(--color-accent)' : 'var(--color-text-1)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
+        <div
+          style={{
+            fontWeight: isActive ? 600 : 400,
+            color: isActive ? 'var(--color-accent)' : 'var(--color-text-1)',
+            overflow: 'hidden',
+            textOverflow: 'ellipsis',
+            whiteSpace: 'nowrap',
+          }}
+        >
           {track.title}
         </div>
-        <div style={{ fontSize: '0.8125rem', color: 'var(--color-text-2)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>
+        <div
-          {track.artistName}{showAlbum && ` · ${track.albumTitle}`}
+          style={{
+            fontSize: '0.8125rem',
+            color: 'var(--color-text-2)',
+            overflow: 'hidden',
+            textOverflow: 'ellipsis',
+            whiteSpace: 'nowrap',
+          }}
+        >
+          {track.artistName}
+          {showAlbum && ` · ${track.albumTitle}`}
         </div>
       </div>
       <AvailabilityBadge availability={track.availability} />
       <div style={{ display: 'flex', alignItems: 'center', gap: '0.5rem' }}>
-        <span style={{ fontSize: '0.8125rem', color: 'var(--color-text-3)', minWidth: '3rem', textAlign: 'right' }}>
+        <span
+          style={{
+            fontSize: '0.8125rem',
+            color: 'var(--color-text-3)',
+            minWidth: '3rem',
+            textAlign: 'right',
+          }}
+        >
           {formatDuration(track.durationMs)}
         </span>
         <TrackContextMenu

src/config/env.ts

@@ -1 +1,2 @@
-export const DEFAULT_API_BASE_URL = import.meta.env.PUBLIC_API_BASE_URL ?? '/api/v1';
+export const DEFAULT_API_BASE_URL =
+  import.meta.env.PUBLIC_API_BASE_URL ?? '/api/v1';

src/config/instances.ts

@@ -0,0 +1,186 @@
+/*
+ * Multi-instance backend registry + per-backend scoped storage.
+ *
+ * The web UI is backend-agnostic: it can connect to any server speaking the
+ * `/api/v1` contract. Everything we persist (auth tokens, cached prefs, …) is
+ * therefore bound to the *instance it came from* — never global. Each saved
+ * backend gets a stable `id` derived from its base URL, and every persisted key
+ * lives under the `mcma:<id>:` namespace so switching backends can never mix
+ * one server's session/cache into another's.
+ *
+ * Layout in localStorage:
+ *   mcma:instances              -> Instance[]            (the saved-backends registry)
+ *   mcma:activeInstance         -> <id>                  (which one is current)
+ *   mcma:<id>:auth              -> persisted auth slice  (per-backend)
+ *   mcma:<id>:<key>             -> any other scoped value
+ */
+
+export interface Instance {
+  id: string;
+  baseUrl: string;
+  name: string;
+  lastUsedAt: number;
+}
+
+const REGISTRY_KEY = 'mcma:instances';
+const ACTIVE_KEY = 'mcma:activeInstance';
+
+// pre-multi-instance keys, migrated once on first load
+const LEGACY_URL_KEY = 'mcma_api_base_url';
+const LEGACY_AUTH_KEY = 'mcma_auth';
+
+function normalizeUrl(url: string): string {
+  return url.trim().replace(/\/+$/, '');
+}
+
+/** Stable, readable id from a base URL — also serves as the storage namespace. */
+export function instanceIdFromUrl(url: string): string {
+  const stripped = normalizeUrl(url)
+    .toLowerCase()
+    .replace(/^https?:\/\//, '');
+  const slug = stripped.replace(/[^a-z0-9]+/g, '-').replace(/^-+|-+$/g, '');
+  return slug || 'default';
+}
+
+function defaultName(baseUrl: string): string {
+  try {
+    const u = new URL(
+      /^https?:\/\//.test(baseUrl) ? baseUrl : `http://${baseUrl}`,
+    );
+    return u.host || baseUrl;
+  } catch {
+    return baseUrl;
+  }
+}
+
+function readRegistry(): Instance[] {
+  try {
+    const raw = localStorage.getItem(REGISTRY_KEY);
+    return raw ? (JSON.parse(raw) as Instance[]) : [];
+  } catch {
+    return [];
+  }
+}
+
+function writeRegistry(list: Instance[]): void {
+  try {
+    localStorage.setItem(REGISTRY_KEY, JSON.stringify(list));
+  } catch {
+    /* storage unavailable */
+  }
+}
+
+/** Saved backends, most-recently-used first. */
+export function listInstances(): Instance[] {
+  return readRegistry().sort((a, b) => b.lastUsedAt - a.lastUsedAt);
+}
+
+/** Add (or refresh) a backend in the registry and return its record. */
+export function upsertInstance(url: string, name?: string): Instance {
+  const baseUrl = normalizeUrl(url);
+  const id = instanceIdFromUrl(baseUrl);
+  const list = readRegistry();
+  const existing = list.find((i) => i.id === id);
+  const inst: Instance = {
+    id,
+    baseUrl,
+    name: name ?? existing?.name ?? defaultName(baseUrl),
+    lastUsedAt: Date.now(),
+  };
+  writeRegistry(
+    existing ? list.map((i) => (i.id === id ? inst : i)) : [...list, inst],
+  );
+  return inst;
+}
+
+/** Remove a backend and wipe every scoped key it owns. */
+export function removeInstance(id: string): void {
+  writeRegistry(readRegistry().filter((i) => i.id !== id));
+  clearScope(id);
+  if (getActiveInstanceId() === id) {
+    const next = listInstances()[0];
+    if (next) setActiveInstanceId(next.id);
+    else localStorage.removeItem(ACTIVE_KEY);
+  }
+}
+
+export function getActiveInstanceId(): string | null {
+  return localStorage.getItem(ACTIVE_KEY);
+}
+
+export function setActiveInstanceId(id: string): void {
+  localStorage.setItem(ACTIVE_KEY, id);
+}
+
+export function getActiveInstance(): Instance | null {
+  const id = getActiveInstanceId();
+  if (!id) return null;
+  return readRegistry().find((i) => i.id === id) ?? null;
+}
+
+/** Build the namespaced localStorage key for a value scoped to a backend. */
+export function scopedKey(
+  key: string,
+  instanceId: string | null = getActiveInstanceId(),
+): string {
+  return `mcma:${instanceId ?? 'none'}:${key}`;
+}
+
+/**
+ * Per-backend key/value store. Reads/writes are no-ops when no instance is
+ * active, so callers never have to special-case the unconnected state.
+ */
+export const instanceStorage = {
+  get(key: string): string | null {
+    const id = getActiveInstanceId();
+    return id ? localStorage.getItem(scopedKey(key, id)) : null;
+  },
+  set(key: string, value: string): void {
+    const id = getActiveInstanceId();
+    if (!id) return;
+    try {
+      localStorage.setItem(scopedKey(key, id), value);
+    } catch {
+      /* storage unavailable */
+    }
+  },
+  remove(key: string): void {
+    const id = getActiveInstanceId();
+    if (id) localStorage.removeItem(scopedKey(key, id));
+  },
+};
+
+function clearScope(id: string): void {
+  const prefix = `mcma:${id}:`;
+  const toRemove: string[] = [];
+  for (let i = 0; i < localStorage.length; i++) {
+    const k = localStorage.key(i);
+    if (k && k.startsWith(prefix)) toRemove.push(k);
+  }
+  toRemove.forEach((k) => localStorage.removeItem(k));
+}
+
+/** One-time migration of the old single-backend keys into the namespaced model. */
+function migrateLegacy(): void {
+  try {
+    const legacyUrl = localStorage.getItem(LEGACY_URL_KEY);
+    if (!legacyUrl || readRegistry().length > 0) return;
+    const inst = upsertInstance(legacyUrl);
+    const legacyAuth = localStorage.getItem(LEGACY_AUTH_KEY);
+    if (legacyAuth)
+      localStorage.setItem(scopedKey('auth', inst.id), legacyAuth);
+    setActiveInstanceId(inst.id);
+    localStorage.removeItem(LEGACY_URL_KEY);
+    localStorage.removeItem(LEGACY_AUTH_KEY);
+  } catch {
+    /* best-effort */
+  }
+}
+
+// Fold any pre-multi-instance keys into the namespaced model on first load.
+// We deliberately do NOT seed an instance from the env default: before the
+// user connects there is no active instance, getApiBaseUrl() falls back to the
+// env default, and the connect flow registers the real backend.
+if (typeof localStorage !== 'undefined') {
+  migrateLegacy();
+}

src/config/runtime-config.ts

@@ -1,15 +1,22 @@
 import { DEFAULT_API_BASE_URL } from './env';
+import {
+  getActiveInstance,
+  upsertInstance,
+  setActiveInstanceId,
+} from './instances';
 
-const STORAGE_KEY = 'mcma_api_base_url';
+/**
-
+ * Base-URL resolution. The active backend (chosen via ConnectPage) wins; if
+ * none is active we fall back to the env default. See `instances.ts` for the
+ * per-backend registry that backs this — every persisted value is namespaced
+ * to the instance it came from.
+ */
 export function getApiBaseUrl(): string {
-  return localStorage.getItem(STORAGE_KEY) ?? DEFAULT_API_BASE_URL;
+  return getActiveInstance()?.baseUrl ?? DEFAULT_API_BASE_URL;
 }
 
+/** Register a backend and make it the active one (used by the connect flow). */
 export function setApiBaseUrl(url: string): void {
-  localStorage.setItem(STORAGE_KEY, url);
+  const inst = upsertInstance(url);
-}
+  setActiveInstanceId(inst.id);
-
-export function clearApiBaseUrl(): void {
-  localStorage.removeItem(STORAGE_KEY);
 }

src/features/admin/AdminPage.tsx

@@ -1,4 +1,10 @@
 import { Window } from 'modern-sk';
 export function AdminPage() {
-  return <div style={{ padding: '1.5rem' }}><Window title="Admin"><p style={{ color: 'var(--color-text-2)' }}>Coming soon</p></Window></div>;
+  return (
+    <div style={{ padding: '1.5rem' }}>
+      <Window title="Admin">
+        <p style={{ color: 'var(--color-text-2)' }}>Coming soon</p>
+      </Window>
+    </div>
+  );
 }

src/features/album-detail/AlbumDetailPage.tsx

@@ -1,6 +1,9 @@
 import { useParams, useNavigate } from 'react-router';
 import { ScrollArea, IconButton, Button } from 'modern-sk';
-import { useGetAlbumQuery, useGetAlbumTracksQuery } from '../../api/endpoints/library';
+import {
+  useGetAlbumQuery,
+  useGetAlbumTracksQuery,
+} from '../../api/endpoints/library';
 import { TrackRow } from '../../components/track/TrackRow';
 import { LoadingSkeleton } from '../../components/common/LoadingSkeleton';
 import { ErrorState } from '../../components/common/ErrorState';
@@ -19,11 +22,20 @@ export function AlbumDetailPage() {
   const tracksQuery = useGetAlbumTracksQuery(albumId ?? '', { skip: !albumId });
 
   if (albumQuery.isLoading || tracksQuery.isLoading) {
-    return <div style={{ padding: '1.5rem' }}><LoadingSkeleton rows={10} /></div>;
+    return (
+      <div style={{ padding: '1.5rem' }}>
+        <LoadingSkeleton rows={10} />
+      </div>
+    );
   }
 
   if (albumQuery.isError) {
-    return <ErrorState message="Failed to load album" onRetry={() => albumQuery.refetch()} />;
+    return (
+      <ErrorState
+        message="Failed to load album"
+        onRetry={() => albumQuery.refetch()}
+      />
+    );
   }
 
   const album = albumQuery.data;
@@ -32,52 +44,139 @@ export function AlbumDetailPage() {
 
   const handlePlayAll = () => {
     if (!tracks.length || !album) return;
-    dispatch(setQueue({
+    dispatch(
-      entries: tracks.map((t) => ({
+      setQueue({
-        trackId: t.id,
+        entries: tracks.map((t) => ({
-        title: t.title,
+          trackId: t.id,
-        artistName: t.artistName,
+          title: t.title,
-        albumTitle: t.albumTitle,
+          artistName: t.artistName,
-        durationMs: t.durationMs,
+          albumTitle: t.albumTitle,
-        albumArtUrl: t.albumArtUrl,
+          durationMs: t.durationMs,
-      })),
+          albumArtUrl: t.albumArtUrl,
-      source: 'album',
+        })),
-      sourceId: album.id,
+        source: 'album',
-      sourceName: album.title,
+        sourceId: album.id,
-    }));
+        sourceName: album.title,
+      }),
+    );
   };
 
   return (
     <div style={{ display: 'flex', flexDirection: 'column', height: '100%' }}>
       {/* header */}
-      <div style={{ padding: '1.25rem 1.5rem', borderBottom: '1px solid var(--color-border)', display: 'flex', alignItems: 'center', gap: '1rem', flexShrink: 0 }}>
+      <div
-        <IconButton variant="ghost" size="sm" onClick={() => navigate(-1)} aria-label="Back">←</IconButton>
+        style={{
-        <div style={{ display: 'flex', gap: '1.5rem', alignItems: 'flex-end', flex: 1 }}>
+          padding: '1.25rem 1.5rem',
+          borderBottom: '1px solid var(--color-border)',
+          display: 'flex',
+          alignItems: 'center',
+          gap: '1rem',
+          flexShrink: 0,
+        }}
+      >
+        <IconButton
+          variant="ghost"
+          size="sm"
+          onClick={() => navigate(-1)}
+          aria-label="Back"
+        >
+          ←
+        </IconButton>
+        <div
+          style={{
+            display: 'flex',
+            gap: '1.5rem',
+            alignItems: 'flex-end',
+            flex: 1,
+          }}
+        >
           {artUrl ? (
-            <img src={artUrl} alt={album?.title} width={96} height={96} style={{ borderRadius: 8, objectFit: 'cover', flexShrink: 0 }} />
+            <img
+              src={artUrl}
+              alt={album?.title}
+              width={96}
+              height={96}
+              style={{ borderRadius: 8, objectFit: 'cover', flexShrink: 0 }}
+            />
           ) : (
-            <div style={{ width: 96, height: 96, borderRadius: 8, background: 'var(--color-surface-3)', flexShrink: 0, display: 'flex', alignItems: 'center', justifyContent: 'center', fontSize: '2.5rem' }}>💿</div>
+            <div
+              style={{
+                width: 96,
+                height: 96,
+                borderRadius: 8,
+                background: 'var(--color-surface-3)',
+                flexShrink: 0,
+                display: 'flex',
+                alignItems: 'center',
+                justifyContent: 'center',
+                fontSize: '2.5rem',
+              }}
+            >
+              💿
+            </div>
           )}
           <div>
-            <p style={{ margin: 0, fontSize: '0.75rem', color: 'var(--color-text-3)', textTransform: 'uppercase', letterSpacing: '0.05em' }}>Album</p>
+            <p
-            <h1 style={{ margin: '0.25rem 0', fontSize: '1.5rem', fontWeight: 700 }}>{album?.title}</h1>
+              style={{
-            <p style={{ margin: 0, color: 'var(--color-text-2)', fontSize: '0.875rem' }}>
+                margin: 0,
+                fontSize: '0.75rem',
+                color: 'var(--color-text-3)',
+                textTransform: 'uppercase',
+                letterSpacing: '0.05em',
+              }}
+            >
+              Album
+            </p>
+            <h1
+              style={{
+                margin: '0.25rem 0',
+                fontSize: '1.5rem',
+                fontWeight: 700,
+              }}
+            >
+              {album?.title}
+            </h1>
+            <p
+              style={{
+                margin: 0,
+                color: 'var(--color-text-2)',
+                fontSize: '0.875rem',
+              }}
+            >
               {album?.artistName}
               {album?.year && ` · ${album.year}`}
-              {album && ` · ${album.trackCount} tracks · ${formatDuration(album.totalDurationMs)}`}
+              {album &&
+                ` · ${album.trackCount} tracks · ${formatDuration(album.totalDurationMs)}`}
             </p>
           </div>
         </div>
-        <Button variant="primary" onClick={handlePlayAll} disabled={!tracks.length}>▶ Play</Button>
+        <Button
+          variant="primary"
+          onClick={handlePlayAll}
+          disabled={!tracks.length}
+        >
+          ▶ Play
+        </Button>
       </div>
 
       {/* tracks */}
       <ScrollArea style={{ flex: 1 }}>
         {tracksQuery.isLoading && <LoadingSkeleton rows={10} />}
-        {tracksQuery.isError && <ErrorState message="Failed to load tracks" onRetry={() => tracksQuery.refetch()} />}
+        {tracksQuery.isError && (
-        {!tracksQuery.isLoading && !tracksQuery.isError && tracks.length === 0 && (
+          <ErrorState
-          <EmptyState icon="♫" title="No tracks" description="This album has no tracks." />
+            message="Failed to load tracks"
+            onRetry={() => tracksQuery.refetch()}
+          />
         )}
+        {!tracksQuery.isLoading &&
+          !tracksQuery.isError &&
+          tracks.length === 0 && (
+            <EmptyState
+              icon="♫"
+              title="No tracks"
+              description="This album has no tracks."
+            />
+          )}
         {tracks.map((track, i) => (
           <TrackRow key={track.id} track={track} index={i} />
         ))}