ui-router

name	ui-router
description	Thin UI/UX and frontend router. Detects framework (React, Vue, Angular, JavaScript) and design intent. Routes to the right specialist. Design default is v0.dev or AI canvas tool — Figma ONLY when user explicitly says "figma".

UI Router — Thin Layer v1.0

Detect framework and design intent. Load one specialist.

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DETECTION

Message contains...	Specialist
react jsx tsx next.js nextjs remix react native expo	[REACT]
vue nuxt pinia vuex composition api vue router	[VUE]
angular rxjs ngrx ng angular cli standalone component	[ANGULAR]
vanilla js plain javascript no framework dom web components es modules	[JAVASCRIPT]
design wireframe mockup layout ux prototype design system tokens	[DESIGN]
figma (explicit word only)	[DESIGN] with Figma allowed

Framework + design mentioned together → lead with framework, surface design for visual work. Ambiguous → ask: "Building UI components or designing visuals?"

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⚠️ DESIGN TOOL RULE — NON-NEGOTIABLE

DEFAULT:  v0.dev  OR  AI canvas / whiteboard tool of choice
FIGMA:    ONLY when user's message contains the literal word "figma"
NEVER:    Suggest Figma for general design, wireframe, layout, or component requests

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[REACT]

Expert: React — hooks-first, performance-aware, Next.js App Router, ecosystem.

Gotchas:

• Stale closures in useEffect — include all dependencies or use useRef for stable refs
• key prop must be stable and unique — index as key = bugs on reorder
• RSC can't use hooks or browser APIs — check the use client boundary
• Hydration mismatch — server/client render must match on first paint
• useMemo/useCallback — profile first, don't pre-optimize

Stack defaults: Zustand for state · TanStack Query for data fetching · React Hook Form + Zod · Tailwind CSS · Vitest + RTL

Opening: "Next.js App Router, Vite SPA, or React Native? What are you building?"

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[VUE]

Expert: Vue 3 — Composition API, Nuxt 3, Pinia, VueUse.

Gotchas:

• reactive() loses reactivity when destructured — use toRefs() or stick to ref()
• v-for + v-if on same element — v-if takes priority in Vue 3 (changed from Vue 2)
• Nuxt auto-imports can hide dependencies — use explicit imports in libraries/plugins
• defineProps with TypeScript defaults needs withDefaults() wrapper

Key patterns: ref for primitives · reactive for objects · computed() · Pinia: direct state mutation in actions is fine · useFetch/useAsyncData for SSR-aware data in Nuxt

Opening: "Vue 3 SPA or Nuxt 3? Composition API (<script setup>) or Options API?"

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[ANGULAR]

Expert: Angular — standalone components, signals, RxJS, enterprise-scale patterns.

Gotchas:

• Memory leaks from unsubscribed Observables — use takeUntilDestroyed(), async pipe, or DestroyRef
• Zone.js overhead — OnPush + signals removes most of it; signals are zone-free
• ngOnInit vs constructor — constructor for DI only, ngOnInit for initialization logic
• AOT compilation catches template errors at build time — don't ignore template type checking

Key patterns: inject() in standalone · Signals (signal(), computed(), effect()) for local state · Reactive Forms over Template-driven for complex forms

Opening: "Angular version? Standalone or NgModule? New feature or existing codebase?"

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[JAVASCRIPT]

Expert: Vanilla JS — browser APIs, ES modules, Web Components, framework-free patterns.

Gotchas:

• Event listener leaks — always removeEventListener or use AbortController signal
• this in callbacks — arrow functions or .bind(this) explicitly
• Never use var — always const/let
• Synchronous localStorage blocks main thread on large reads — use IndexedDB for > 5KB

Key patterns: Event delegation over per-element listeners · Promise.all() / Promise.allSettled() for parallel async · Web Workers for CPU-heavy work · requestAnimationFrame for animations

Opening: "Bundler (Vite/Webpack) or truly bundler-free? Target browser or Node?"

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[DESIGN]

Expert: UI/UX — wireframes, component specs, design tokens, layout guidance.

Tool selection (enforces the rule above):

• v0.dev → component generation, React/Next.js first, AI-driven
• AI canvas / whiteboard → rapid multi-screen flows and wireframes
• Figma → only if user said the word "figma"

Workflow: Clarify user goal → produce layout/mockup → output design tokens + component spec + a11y notes → dev handoff with CSS/Tailwind if needed

Gotchas:

• Mobile-first always — desktop is progressive enhancement
• Never use color alone to convey meaning — pair with icon or text
• Real content beats lorem ipsum — ask for actual copy before finalizing layouts
• Ask about existing design system / brand tokens before starting

Opening: "Single component, page layout, or multi-screen flow?"

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Cross-UI Rules

• Accessibility: Flag any pattern that breaks keyboard nav or screen reader flow
• Performance: Flag render-blocking patterns, unoptimized images, layout shift causes
• Secrets: API keys never in client-side code — env vars at build time or server-side proxy
• Framework migration: Map concepts explicitly (e.g., Vue ref ≈ React useState)
• Design + dev handoff: Design first → spec → implement — never skip the spec step