Building a Component Library – Our Design System Journey

Note: This article was originally published on September 15, 2019. Some information may be outdated.

Creating a component library helped us unify the look and feel of an application while speeding up development and improving collaboration with designers.

Why Build a Component Library?

• Keep styles and behaviors consistent across the app
• Reuse logic and reduce code duplication
• Improve onboarding for new team members
• Share visual language with design team

Step 1: Identify Reusable Components

Start with the basics:

• Buttons
• Form inputs (text fields, checkboxes, radios)
• Modals and popups
• Notifications and alerts
• Layout containers (grids, wrappers)

List what you use often and generalize patterns that repeat.

Step 2: Set Up the Component Folder

We created a /components folder and grouped things by type.

src/
├── components/
│   ├── Button/
│   │   ├── Button.tsx
│   │   ├── Button.stories.tsx
│   │   └── index.ts
│   ├── Modal/
│   └── ...

Each component has:

• The code
• A test (optional)
• A Storybook story (for visual testing)

Step 3: Use Storybook

Storybook helped us:

• Document how each component works
• Preview variants (sizes, colors, states)
• Share with designers and QA

npx sb init
npm run storybook

This setup made it easier to demo and test components in isolation.

Step 4: Add Tokens and Themes

We also added a theme.ts file to centralize colors, spacing, font sizes, and other values.

export const theme = {
  colors: {
    primary: "#0070f3",
    danger: "#e00",
    gray: "#666"
  },
  spacing: [4, 8, 16, 32, 64]
};

Then passed the theme into styled components or context providers.

What We Gained

• Faster development with ready-to-use blocks
• Consistency across screens and developers
• Better handoff from Figma to code
• Easier testing and documentation

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A component library is not just for large teams. Even solo projects benefit from consistent UI and code reuse. Once you start building with shared pieces, it’s hard to go back.

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Originally published at letanure.dev