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+---
+name: pick-ui-library
+description: Pick the right library for a given frontend task from a curated, opinionated list — numbers, OTP inputs, charts, command menus, virtualization, drag and drop, toasts, state, styling, and more. Only runs when explicitly invoked; it does not trigger on its own.
+disable-model-invocation: true
+---
+
+# Picking The Right Library
+
+## Initial Response
+
+When this skill is first invoked without a specific question, respond only with:
+
+> I'm ready to pick the right library for your task, my picks come from Emil Kowalski's curated list.
+
+Do not provide any other information until the user asks a question.
+
+A lookup skill. When invoked with a task ("I need toasts", "what should I use for drag and drop?"), match the task to the curated list below and recommend the library. These are deliberate, taste-driven picks — don't substitute alternatives outside this list unless the user asks for one or the task genuinely isn't covered.
+
+## How to use this
+
+1. **Identify the task**, not the library the user named. "I need to show a dropdown" is a UI-primitives task (base-ui), even if they asked about something else.
+2. **Check what's already installed.** Look at `package.json` first. If the project already uses a listed library, use it. If it uses a competitor (e.g. react-window instead of Virtuoso), flag the recommendation but don't churn the dependency without being asked.
+3. **Recommend one library**, state what it's for in one sentence, and install/wire it up if that's part of the request. Don't present a menu of options when the list has a clear answer.
+4. If the task isn't covered by the list, say so explicitly and recommend from your own knowledge — but be clear you've left the curated list.
+
+## The list
+
+### UI components & primitives
+
+| Task | Library |
+| --- | --- |
+| Unstyled, accessible UI components (dialogs, popovers, menus, selects…) | [base-ui](https://base-ui.com) |
+| Command menus (⌘K palettes) | [cmdk](https://cmdk.paco.me) |
+| Toasts / notifications | [Sonner](https://sonner.emilkowal.ski) |
+| One-time password / verification code inputs | [input-otp](https://input-otp.rodz.dev) |
+| Customizable GUIs / control panels | [Leva](https://github.com/pmndrs/leva) — [dialkit](https://joshpuckett.me/dialkit) is an alternative |
+
+### Motion & visuals
+
+| Task | Library |
+| --- | --- |
+| General-purpose animation (springs, layout animations, enter/exit) | [motion](https://motion.dev) (Framer Motion) |
+| Animating numbers (counters, prices, stats) | [NumberFlow](https://number-flow.barvian.me) |
+| Animated text components | [torph](https://torph.lochie.me/) |
+| 3D globes | [Cobe](https://cobe.vercel.app) |
+| Dynamic OG images (HTML/CSS → SVG/PNG) | [Satori](https://github.com/vercel/satori) |
+| Syntax highlighting | [shiki](https://shiki.style) |
+
+Reach for motion when you need springs, layout animations, exit animations, or gesture-driven values. A simple hover or fade doesn't need it — plain CSS transitions are the right tool there.
+
+### Charts
+
+| Task | Library |
+| --- | --- |
+| Real-time / streaming charts | [Liveline](https://github.com/benjitaylor/liveline) |
+| General charts (static or interactive dashboards) | [recharts](https://recharts.org) |
+
+The split: if data points arrive live and the chart scrolls with time, use Liveline. Everything else is recharts.
+
+### Interaction & performance
+
+| Task | Library |
+| --- | --- |
+| Drag and drop | [dnd kit](https://dndkit.com) |
+| Virtualization (long lists, large tables) | [Virtuoso](https://virtuoso.dev) |
+
+### State & styling
+
+| Task | Library |
+| --- | --- |
+| State management | [zustand](https://zustand.docs.pmnd.rs) |
+| Constructing `className` strings conditionally | [clsx](https://github.com/lukeed/clsx) |
+| Type-safe, variant-driven styling for Tailwind | [cva](https://cva.style) |
+| Theme switching / dark mode (no flash on load) | [next-themes](https://github.com/pacocoursey/next-themes) |
+
+The styling split: clsx for ad-hoc conditional classes; cva when a component has real variants (size, intent, state) that deserve a typed API. They compose — cva uses clsx-style inputs internally.
+
+## Common mismatches to catch
+
+- **Toasts built by hand or with a modal library** → Sonner exists for exactly this.
+- **A `<div>`-based dropdown/dialog with manual focus handling** → base-ui, which handles accessibility, focus trapping, and dismissal.
+- **Animating a number by re-rendering text** → NumberFlow handles digit transitions properly.
+- **Rendering a 1,000+ row list directly** → Virtuoso before reaching for pagination hacks.
+- **A `useState`-per-component web of props for shared state** → zustand.
+- **Template-literal className ternaries three conditions deep** → clsx (or cva if it's variant-shaped).
+
+## Project constraints (Second Brain LMS — override the list above)
+
+Source: emilkowalski/skills @ 715c180 (MIT). Section added for this repo on 20261111.
+
+- UI primitives: this project uses shadcn (style "base-nova") on top of @base-ui/react. For dialogs, menus, selects and popovers run `npx shadcn add <component>` and restyle it to DS-2; do not import raw base-ui parts in feature code. Never add Radix directly.
+- Design system DS-2 Aubade (SecondBrainTech/02-Стандарты/Дизайн-LMS/DESIGN.md) wins over any library default: radius 2px, 2px borders, Fira Mono, hard offset shadows (4px 4px 0, no blur), no gradients, one accent #E8F0D8, red only for errors.
+- Motion: DS-2 hover/active physics (translate ±2px, 0.1s ease) and plain CSS transitions. At most ONE prominent animated element per page (an animated number, hero or background). Under prefers-reduced-motion there is no motion at all. Already installed for this: @number-flow/react (course progress percent) and vaul (mobile drawer). Do NOT add motion, torph, Cobe or other animation libraries without the owner's explicit approval.
+- Never install a new dependency without asking first: name the package, its size and why the existing stack can't do it.
+- Already installed and preferred: sonner (src/components/ui/sonner.tsx), cmdk (src/components/admin/admin-command-menu.tsx), vaul via src/components/shared/responsive-dialog.tsx, @number-flow/react, @dnd-kit, clsx, class-variance-authority, next-themes, lucide-react, tailwind-merge.