Architecture

This document outlines the architecture and design decisions behind the GT Design System, providing insights for contributors and maintainers.

System Overview

The GT Design System follows atomic design principles and is structured as a monorepo containing design tokens, React components, and supporting packages.

text

gt-design-system/
├── packages/
│   ├── tokens/           # Design tokens (Style Dictionary)
│   ├── react/            # React components
│   ├── eslint/           # ESLint configurations
│   └── typescript/       # TypeScript configurations
├── apps/
│   ├── docs/             # VitePress documentation
│   └── storybook/        # Component playground
└── tools/                # Build and development tools

Design Principles

1. Token-Driven Design

All visual properties stem from design tokens, ensuring consistency and maintainability.

typescript

// Components use tokens, not hard-coded values
const buttonStyles = {
  backgroundColor: GtColorPrimaryGold,
  padding: `${GtSpacing3} ${GtSpacing6}`,
  borderRadius: GtBorderRadiusBase,
};

2. Component Composition

Components are designed to be composable and flexible:

typescript

// Base component with extensible props
interface ButtonProps extends React.ButtonHTMLAttributes<HTMLButtonElement> {
  variant?: 'primary' | 'secondary' | 'outline';
  size?: 'sm' | 'md' | 'lg';
}

3. Progressive Enhancement

Components work without JavaScript and enhance with interactivity:

Semantic HTML foundation
CSS-only base styling
JavaScript for enhanced behavior

Package Architecture

Design Tokens (`@gtalumni-la/tokens`)

Technology Stack:

Style Dictionary for token generation
JSON source files for token definitions
Multiple output formats (CSS, SCSS, JS, TS, JSON)

Structure:

text

packages/tokens/
├── src/
│   ├── tokens.ts         # Generated TypeScript exports
│   └── tokens.d.ts       # Type definitions
├── tokens/               # Source JSON files
│   ├── colors.json
│   ├── spacing.json
│   └── typography.json
├── dist/                 # Generated outputs
│   ├── css/
│   ├── scss/
│   ├── js/
│   ├── ts/
│   └── json/
└── config.js            # Style Dictionary configuration

Token Generation Flow:

JSON source files define raw token values
Style Dictionary processes and transforms tokens
Multiple format outputs generated automatically
TypeScript types generated for type safety

React Components (`@gtalumni-la/react`)

Technology Stack:

React 18+ with TypeScript
Rollup for bundling
Vitest for testing
ESLint and Prettier for code quality

Structure:

text

packages/react/
├── src/
│   ├── Button.tsx        # Component implementation
│   ├── Button.stories.tsx # Storybook stories
│   ├── __test__/         # Component tests
│   └── index.ts          # Package exports
├── dist/                 # Built outputs
└── rollup.config.js      # Build configuration

Component Design Patterns:

Compound components for complex UI
Render props for flexible composition
Forward refs for DOM access
Generic types for reusable patterns

Build System

Monorepo Management

Turborepo orchestrates builds across packages:

json

{
  "pipeline": {
    "build": {
      "dependsOn": ["^build"],
      "outputs": ["dist/**"]
    },
    "test": {
      "dependsOn": ["build"]
    }
  }
}

Benefits:

Intelligent caching of build outputs
Parallel execution of independent tasks
Dependency-aware build ordering
Remote caching for CI/CD

Package Bundling

Rollup Configuration:

ES modules and CommonJS outputs
TypeScript compilation
Tree-shaking optimization
Source map generation

javascript

export default {
  input: 'src/index.ts',
  output: [
    { file: 'dist/index.esm.js', format: 'es' },
    { file: 'dist/index.cjs.js', format: 'cjs' },
  ],
  external: ['react', 'react-dom'],
  plugins: [typescript(), resolve(), commonjs()],
};

Type Safety

Design Token Types

Tokens are strongly typed for better developer experience:

typescript

// Generated types from Style Dictionary
export type GTColorKey =
  | 'GT_COLOR_PRIMARY_GOLD'
  | 'GT_COLOR_PRIMARY_NAVY'
  | 'GT_COLOR_SECONDARY_BLUE';

export const getGTColor = (key: GTColorKey): string => {
  return GT_COLORS[key];
};

Component Props

All components have comprehensive TypeScript interfaces:

typescript

export interface ButtonProps
  extends React.ButtonHTMLAttributes<HTMLButtonElement> {
  children?: React.ReactNode;
  variant?: ButtonVariant;
  size?: ButtonSize;
}

// Union types for strict prop validation
export type ButtonVariant = 'primary' | 'secondary' | 'outline';
export type ButtonSize = 'sm' | 'md' | 'lg';

Testing Strategy

Unit Testing

Vitest + Testing Library:

Component behavior testing
Accessibility compliance
Props validation
Event handling

typescript

test('Button renders with correct variant styles', () => {
  render(<Button variant="primary">Test</Button>)
  const button = screen.getByRole('button')
  expect(button).toHaveClass('button--primary')
})

Visual Regression Testing

Storybook + Chromatic:

Automated visual testing
Cross-browser compatibility
Responsive design validation
Component state coverage

Integration Testing

Cypress (Future):

End-to-end workflows
Real browser testing
Accessibility auditing
Performance monitoring

Performance Considerations

Bundle Optimization

Tree Shaking: Components can be imported individually
Code Splitting: Lazy loading for non-critical components
Bundle Analysis: Regular monitoring of package sizes

typescript

// Tree-shakeable imports
import { Button } from '@gtalumni-la/react';
// Not: import * as GTDesign from '@gtalumni-la/react'

Runtime Performance

Minimal Re-renders: Optimized component updates
CSS-in-CSS: No runtime style computation
Lazy Loading: Deferred loading of heavy components

Build Performance

Turborepo Caching: Aggressive caching strategy
Parallel Builds: Independent package building
Incremental Builds: Only rebuild changed packages

Accessibility Architecture

WCAG 2.1 AA Compliance

All components meet accessibility standards:

Semantic HTML: Proper element usage
ARIA Support: Comprehensive labeling
Keyboard Navigation: Full keyboard operability
Screen Reader: Compatible with assistive technology

Testing Integration

Accessibility testing is built into the development workflow:

typescript

// Automated a11y testing
test('Button is accessible', async () => {
  const { container } = render(<Button>Test</Button>)
  const results = await axe(container)
  expect(results).toHaveNoViolations()
})

Documentation Architecture

VitePress Setup

Static site generation with:

Markdown-based: Easy content authoring
Vue Components: Interactive examples
Version Management: Support for multiple versions
GitHub Pages: Automated deployment

Component Documentation

Each component includes:

API Reference: Complete prop documentation
Usage Examples: Practical implementation patterns
Accessibility Notes: WCAG compliance details
Design Guidelines: When and how to use

CI/CD Pipeline

GitHub Actions Workflow

yaml

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - name: Install & Test
        run: |
          pnpm install
          pnpm test
          pnpm build

Pipeline Stages:

Lint & Type Check: Code quality validation
Unit Tests: Component functionality testing
Build: Package compilation and bundling
Visual Tests: Storybook visual regression
Deploy: Documentation and Storybook deployment

Release Management

Changesets for version management:

Semantic versioning
Automated changelog generation
NPM publishing automation
GitHub release creation

Security Considerations

Dependency Management

Audit: Regular dependency vulnerability scanning
Updates: Automated dependency updates via Dependabot
Minimal Dependencies: Keep external dependencies minimal

Build Security

Supply Chain: Verify package integrity
Permissions: Minimal required permissions
Secrets: Secure handling of API keys and tokens

Future Architecture

Planned Improvements

Web Components: Framework-agnostic components
CSS Variables: Enhanced theming capabilities
Performance Monitoring: Real-time performance tracking
Multi-Framework: Support for Vue, Angular, Svelte

Scalability Considerations

Micro-frontends: Support for distributed teams
Plugin Architecture: Extensible component system
Theme Engine: Advanced customization capabilities
Internationalization: Multi-language support

Development Workflow

Local Development

bash

# Install dependencies
pnpm install

# Start development
pnpm dev          # All packages in watch mode
pnpm storybook    # Component playground
pnpm docs:dev     # Documentation site

# Testing
pnpm test         # Run all tests
pnpm test:watch   # Watch mode testing
pnpm test:coverage # Coverage reporting

Contributing Process

Issue Creation: Bug reports or feature requests
Branch Creation: Feature or fix branches
Development: Local development with testing
PR Creation: Pull request with description
Review Process: Code review and CI checks
Merge: Automated testing and deployment

This architecture provides a solid foundation for scaling the design system while maintaining quality, performance, and developer experience.

Architecture ​

System Overview ​

Design Principles ​

1. Token-Driven Design ​

2. Component Composition ​

3. Progressive Enhancement ​

Package Architecture ​

Design Tokens (@gtalumni-la/tokens) ​

React Components (@gtalumni-la/react) ​

Build System ​

Monorepo Management ​

Package Bundling ​

Type Safety ​

Design Token Types ​

Component Props ​

Testing Strategy ​

Unit Testing ​

Visual Regression Testing ​

Integration Testing ​

Performance Considerations ​

Bundle Optimization ​

Runtime Performance ​

Build Performance ​

Accessibility Architecture ​

WCAG 2.1 AA Compliance ​

Testing Integration ​

Documentation Architecture ​

VitePress Setup ​

Component Documentation ​

CI/CD Pipeline ​

GitHub Actions Workflow ​

Release Management ​

Security Considerations ​

Dependency Management ​

Build Security ​

Future Architecture ​

Planned Improvements ​

Scalability Considerations ​

Development Workflow ​

Local Development ​

Contributing Process ​

Architecture

System Overview

Design Principles

1. Token-Driven Design

2. Component Composition

3. Progressive Enhancement

Package Architecture

Design Tokens (`@gtalumni-la/tokens`)

React Components (`@gtalumni-la/react`)

Build System

Monorepo Management

Package Bundling

Type Safety

Design Token Types

Component Props

Testing Strategy

Unit Testing

Visual Regression Testing

Integration Testing

Performance Considerations

Bundle Optimization

Runtime Performance

Build Performance

Accessibility Architecture

WCAG 2.1 AA Compliance

Testing Integration

Documentation Architecture

VitePress Setup

Component Documentation

CI/CD Pipeline

GitHub Actions Workflow

Release Management

Security Considerations

Dependency Management

Build Security

Future Architecture

Planned Improvements

Scalability Considerations

Development Workflow

Local Development

Contributing Process