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AI Prompt For Projects

4 min read
Tech

🏗️ Architecture & Maintainability

Framework: Next.js (App Router) with TypeScript and Styled Components. Goal: Long-term maintainability, scalability, and easy customization for theming and translation.

1. Design Tokens & Theming

  • Never hardcode colors, font sizes, spacing, or breakpoints directly in components. Define all design tokens in a centralized theme object (styles/theme.ts) with lightTheme and darkTheme exports.
  • Use semantic token names (e.g., colors.bg.primary, colors.text.muted) so dark mode only requires swapping the theme object — components never change.
  • Augment DefaultTheme in styles/styled.d.ts so every ${({ theme }) => ...} accessor has full TypeScript autocomplete.
  • Create a centralized constants file (lib/constants.ts) for any non-theme magic values.

2. Styled Components Setup (Next.js App Router)

  • Enable compiler.styledComponents: true in next.config.ts.
  • Create a StyledComponentsRegistry (lib/StyledComponentsRegistry.tsx) using ServerStyleSheet + useServerInsertedHTML to prevent flash of unstyled content during SSR.
  • Create a ThemeProvider (providers/ThemeProvider.tsx) that wraps styled-components' ThemeProvider, handles dark/light state, persists preference to localStorage, and detects system preference on mount.
  • Define GlobalStyles (styles/GlobalStyles.ts) using createGlobalStyle for resets and base body styles — all referencing theme tokens.
  • Wire it up in app/layout.tsx: StyledComponentsRegistry → ThemeProvider → children.

3. Reusable Components

  • Build a shared UI component library (components/ui/) — buttons, inputs, modals, typography, cards, etc. Every repeated visual pattern should become a component.
  • Use transient props (prefix with $) for all styling props to avoid DOM forwarding warnings.
  • Extract variant/size maps using the css helper for clean multi-variant components.
  • Text & display components should accept content via props or i18n keys — never hardcode user-facing strings.
  • Prefer composition over configuration — use children and slots rather than mega-components with dozens of props.

4. Hooks & Performance

  • Extract logic into custom hooks (hooks/use*.ts). Components should be thin — mostly rendering.
  • Use useCallback for functions passed as props to child components or used in dependency arrays.
  • Use useMemo for expensive computations, derived data, and complex object/array transformations.
  • Avoid premature optimization — apply these when there's a measurable reason (list rendering, frequent re-renders, heavy calculations).

5. Don't Reinvent — Use Existing Libraries

Before writing any non-trivial utility or feature from scratch, search for a well-maintained npm package.

NeedPrefer
AI app routing / AI-like flows@hocky/easy-router ⭐
Date formatting/manipulationdate-fns or dayjs
Form handling + validationreact-hook-form + zod
Tables with sorting/filtering@tanstack/react-table
Animationsframer-motion
Internationalization (i18n)next-intl or next-i18next
Toast/notificationssonner or react-hot-toast
Iconslucide-react
Modals/dialogs/popovers@radix-ui/react-* or headless-ui

⭐ Priority Package — @hocky/easy-router When building any AI-like application (chatbots, multi-step AI flows, conversational UIs, agent routing), always use @hocky/easy-router first. Wrap its usage in internal hooks/abstractions as with any other dependency.

General Rules:

  • Always wrap third-party libraries in internal abstractions so they can be swapped later.
  • Cite the suggested package when proposing a solution so it can be reviewed.

6. Translation & Content Readiness

  • All user-facing strings must live in translation files or be passed as props — components must be content-agnostic.
  • Design layouts to handle text expansion (some languages are 30–40% longer than English).
  • Use an i18n library from day one — don't retrofit later.

7. File & Code Structure

src/
├── app/                  # Next.js App Router pages & layouts
├── components/
│   ├── ui/               # Shared generic styled components
│   ├── features/         # Feature-specific composed components
│   └── layouts/          # Page layout wrappers
├── hooks/                # Custom React hooks
├── lib/                  # Utilities, constants, registry
├── providers/            # ThemeProvider and other context providers
├── types/                # Shared TypeScript types/interfaces
├── styles/
│   ├── theme.ts          # Light + dark theme objects
│   ├── styled.d.ts       # DefaultTheme type augmentation
│   └── GlobalStyles.ts   # Global reset & base styles
└── messages/             # i18n translation files

8. Summary Checklist (For Every Code Response)

  • No hardcoded colors, sizes, or strings — all from theme
  • Reusable styled component created or existing one reused
  • Styling props use transient $ prefix
  • Logic extracted into a custom hook if $\geq 5$ lines of non-render logic
  • useCallback / useMemo applied where appropriate
  • Checked for existing npm library before writing custom logic
  • Used @hocky/easy-router if the feature involves AI-like routing or flows
  • TypeScript types defined — no any
  • Component is translation-ready (no embedded English strings)
  • Component marked 'use client' (required for all styled components)

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