Atomic Design with Gluestack UI

Overview

This skill enforces Brad Frost's atomic design methodology adapted for React Native/Expo projects using Gluestack UI v3 + NativeWind v4. It provides clear guidelines for component categorization, directory structure, composition patterns, and testing strategies for each atomic level.

Core Principles

The Atomic Hierarchy

Components are organized into five levels, from simplest to most complex:

Design Tokens Foundation

Design tokens sit below atoms as the foundational layer. In this project, tokens are defined in:

• •components/ui/gluestack-ui-provider/config.ts - Color tokens (primary, secondary, error, success, etc.)
• •tailwind.config.js - Spacing, typography, and other design tokens via NativeWind

Directory Structure

Required Structure

components/
├── ui/                          # Gluestack UI library components (DO NOT MODIFY unless extending)
├── atoms/                       # Project-specific atoms
│   ├── AppIcon/
│   │   ├── index.tsx
│   │   ├── AppIcon.test.tsx
│   │   └── types.ts
│   └── index.ts                 # Barrel export for atoms
├── molecules/                   # Composite simple components
│   ├── SearchField/
│   │   ├── index.tsx
│   │   ├── SearchFieldView.tsx
│   │   ├── SearchField.test.tsx
│   │   └── types.ts
│   └── index.ts
├── organisms/                   # Complex feature components
│   ├── Header/
│   │   ├── index.tsx
│   │   ├── HeaderView.tsx
│   │   ├── Header.test.tsx
│   │   └── types.ts
│   └── index.ts
└── templates/                   # Page layouts
    ├── MainLayout/
    │   ├── index.tsx
    │   ├── MainLayoutView.tsx
    │   └── types.ts
    └── index.ts

features/
└── [feature-name]/
    ├── components/              # Feature-specific components (follow atomic naming)
    │   ├── atoms/
    │   ├── molecules/
    │   └── organisms/
    └── screens/                 # Pages (specific to this feature)

app/                             # Expo Router pages (connect templates with data)

Gluestack UI Components Location

The 40+ Gluestack UI components in components/ui/ serve as the foundation atom library. When building custom components:

1. •Use Gluestack components as atoms - Import from @/components/ui/
2. •Extend when needed - Create project-specific atoms in components/atoms/
3. •Never modify components/ui/ - Except for theme customization in config.ts

Component Classification Rules

Rule 1: Atoms (Building Blocks)

Definition: Smallest functional UI elements that cannot be broken down further.

Characteristics:

• •Stateless and purely presentational
• •Accept props for customization
• •No business logic
• •Highly reusable across the entire app

Gluestack Atoms (use directly from @/components/ui/):

• •Box, Center, HStack, VStack, ScrollView
• •Text, Heading
• •Button, ButtonText, ButtonIcon
• •Input, InputField, InputSlot
• •Icon, Image, Avatar
• •Badge, Divider, Spinner

When to create custom atoms:

• •Project-specific iconography
• •Branded text variants
• •Wrapper components with default styling

/**
 * AppLogo atom - Branded logo component
 * @description Displays the application logo with consistent sizing
 */
const AppLogo = memo(function AppLogo({ size = "md" }: AppLogoProps) {
  return (
    <Image
      source={logoSource}
      className={logoSizes[size]}
      alt="App Logo"
    />
  );
});

Rule 2: Molecules (Simple Compositions)

Definition: Simple groups of atoms functioning together as a unit.

Characteristics:

• •Combines 2-5 atoms
• •Single responsibility (does one thing well)
• •May have isolated UI state (toggle, validation)
• •No external data fetching

Examples:

/**
 * SearchField molecule - Search input with button
 * @description Combines Input and Button atoms for search functionality
 */
const SearchField = memo(function SearchField({
  onSearch,
  placeholder
}: SearchFieldProps) {
  const [value, setValue] = useState("");

  return (
    <HStack space="sm" className="items-center">
      <Input className="flex-1">
        <InputField
          value={value}
          onChangeText={setValue}
          placeholder={placeholder}
        />
      </Input>
      <Button onPress={() => onSearch(value)}>
        <ButtonIcon as={SearchIcon} />
      </Button>
    </HStack>
  );
});

Molecule Checklist:

• • Uses only atoms (Gluestack or custom)
• • Has a single, clear purpose
• • State is UI-only (no business logic)
• • Reusable in multiple contexts

Rule 3: Organisms (Complex Sections)

Definition: Relatively complex components forming distinct interface sections.

Characteristics:

• •Combines molecules and atoms
• •May have feature-specific state
• •Can coordinate child component behavior
• •Represents a standalone section of UI

Examples:

/**
 * ProductCard organism - Complete product display
 * @description Displays product information with actions
 */
const ProductCard = memo(function ProductCard({
  product,
  onAddToCart
}: ProductCardProps) {
  return (
    <Card variant="elevated" size="md">
      <ProductImage source={product.image} />      {/* Atom */}
      <VStack space="sm" className="p-4">
        <Heading size="md">{product.name}</Heading> {/* Atom */}
        <PriceDisplay price={product.price} />      {/* Molecule */}
        <RatingStars rating={product.rating} />     {/* Molecule */}
        <AddToCartButton onPress={onAddToCart} />   {/* Molecule */}
      </VStack>
    </Card>
  );
});

Organism Checklist:

• • Forms a distinct interface section
• • Combines molecules and/or atoms
• • Has clear boundaries
• • May receive data as props (but doesn't fetch)

Rule 4: Templates (Page Layouts)

Definition: Page-level layouts that place components into a structure.

Characteristics:

• •Defines layout skeleton with slots
• •No real content (uses placeholder or children)
• •Handles responsive behavior
• •Manages layout-specific state only

Example:

/**
 * MainLayout template - Primary app layout
 * @description Provides consistent header, content, and footer structure
 */
const MainLayout = memo(function MainLayout({
  children,
  showHeader = true,
  showFooter = true
}: MainLayoutProps) {
  return (
    <SafeAreaView className="flex-1 bg-background-0">
      {showHeader && <Header />}
      <ScrollView className="flex-1">
        {children}
      </ScrollView>
      {showFooter && <Footer />}
    </SafeAreaView>
  );
});

Rule 5: Pages (Screens)

Definition: Specific instances of templates with real content and data.

Characteristics:

• •Connects to global state (Apollo, Context)
• •Handles data fetching
• •Passes data to organisms/molecules
• •Lives in app/ (Expo Router) or features/*/screens/

Example:

/**
 * HomeScreen page - Main home page
 * @description Renders home content with fetched data
 */
export default function HomeScreen() {
  const { data, loading } = useHomeDataQuery();

  return (
    <MainLayout>
      {loading ? (
        <LoadingSpinner />
      ) : (
        <VStack space="lg">
          <FeaturedProducts products={data.featured} />
          <RecentActivity items={data.activity} />
        </VStack>
      )}
    </MainLayout>
  );
}

Validation Rules

Enforcement Checklist

When creating or reviewing components, verify:

1. •

   Correct Directory Placement

   • •Atoms in components/atoms/ or features/*/components/atoms/
   • •Molecules in components/molecules/ or features/*/components/molecules/
   • •Organisms in components/organisms/ or features/*/components/organisms/
   • •Templates in components/templates/
   • •Pages in app/ or features/*/screens/
2. •

   State Appropriateness

   • •Atoms: No state
   • •Molecules: UI state only (useState for toggles, form values)
   • •Organisms: Feature state, may use custom hooks
   • •Templates: Layout state only
   • •Pages: Connected to global state, data fetching
3. •

   Import Direction (dependencies flow upward only)

   code

   Pages → Templates → Organisms → Molecules → Atoms → Design Tokens
   

   • •Atoms MUST NOT import from molecules, organisms, templates, or pages
   • •Molecules MUST NOT import from organisms, templates, or pages
   • •Organisms MUST NOT import from templates or pages
4. •

   Composition Appropriateness

   • •Molecules combine 2-5 atoms
   • •Organisms can be complex but should represent a single interface section
   • •If an organism becomes too large, extract sub-organisms

Common Mistakes to Avoid

Testing by Atomic Level

Quick Reference

Decision Tree: Which Level?

Is it a single, indivisible UI element?
├─ YES → ATOM
└─ NO → Does it combine 2-5 atoms for a single purpose?
         ├─ YES → MOLECULE
         └─ NO → Does it form a distinct interface section?
                  ├─ YES → ORGANISM
                  └─ NO → Is it a layout skeleton?
                           ├─ YES → TEMPLATE
                           └─ NO → PAGE

Gluestack Component Level Map

Reference references/gluestack-mapping.md for the complete mapping of all 40 Gluestack UI components to their atomic levels.

Resources

references/

• •atomic-levels.md - Detailed definitions with comprehensive examples
• •gluestack-mapping.md - Complete Gluestack UI component classification
• •folder-structure.md - Detailed directory structure requirements

scripts/

• •validate_atomic_structure.py - Validates component placement and imports