Unnamed Design System

This repository contains OGP's Unnamed Design System powered by:

• 🏎 Turborepo — High-performance build system for Monorepos
• 🚀 React — JavaScript library for user interfaces
• 🛠 Tsup — TypeScript bundler powered by esbuild
• 📖 Storybook — UI component environment powered by Vite

As well as a few others tools preconfigured:

• TypeScript for static type checking
• ESLint for code linting
• Prettier for code formatting
• Changesets for managing versioning and changelogs
• GitHub Actions for fully automated package publishing

Useful Commands

• pnpm build - Build all packages, including the Storybook site
• pnpm dev - Run all packages locally and preview with Storybook
• pnpm lint - Lint all packages
• pnpm changeset - Generate a changeset
• pnpm clean - Clean up all node_modules and dist folders (runs each package's clean script)

Turborepo

Turborepo is a high-performance build system for JavaScript and TypeScript codebases. It was designed after the workflows used by massive software engineering organizations to ship code at scale. Turborepo abstracts the complex configuration needed for monorepos and provides fast, incremental builds with zero-configuration remote caching.

Using Turborepo simplifies managing your design system monorepo, as you can have a single lint, build, test, and release process for all packages. Learn more about how monorepos improve your development workflow.

Apps & Packages

This Turborepo includes the following packages and applications:

• apps/storybook: Component documentation site with Storybook
• packages/components: Core React components
• packages/theme: Theming config (using TailwindCSS) for components and design system
• tooling/typescript-config: Shared tsconfig.jsons used throughout the Turborepo
• tooling/eslint-config: ESLint preset

Each package and app is 100% TypeScript. Workspaces enables us to "hoist" dependencies that are shared between packages to the root package.json. This means smaller node_modules folders and a better local dev experience. To install a dependency for the entire monorepo, use the -w workspaces flag with pnpm add.

This example sets up your .gitignore to exclude all generated files, other folders like node_modules used to store your dependencies.

Compilation

To make the core library code work across all browsers, we need to compile the raw TypeScript and React code to plain JavaScript. We can accomplish this with tsup, which uses esbuild to greatly improve performance.

Running pnpm build from the root of the Turborepo will run the build command defined in each package's package.json file. Turborepo runs each build in parallel and caches & hashes the output to speed up future builds.

For acme-core, the build command is the following:

tsup src/index.tsx --format esm,cjs --dts --external react

tsup compiles src/index.tsx, which exports all of the components in the design system, into both ES Modules and CommonJS formats as well as their TypeScript types. The package.json for acme-core then instructs the consumer to select the correct format:

{
  "name": "@acme/core",
  "version": "0.0.0",
  "main": "./dist/index.js",
  "module": "./dist/index.mjs",
  "types": "./dist/index.d.ts",
  "sideEffects": false,
}

Run pnpm build to confirm compilation is working correctly. You should see a folder acme-core/dist which contains the compiled output.

acme-core
└── dist
    ├── index.d.ts  <-- Types
    ├── index.js    <-- CommonJS version
    └── index.mjs   <-- ES Modules version

Components

Each file inside of packages/components/src is a component inside our design system. For example:

import * as React from 'react';

export interface ButtonProps {
  children: React.ReactNode;
}

export function Button(props: ButtonProps) {
  return <button>{props.children}</button>;
}

Button.displayName = 'Button';

When adding a new file, ensure the component is also exported from the entry index.tsx file:

import * as React from "react";
export { Button, type ButtonProps } from "./Button";
// Add new component exports here

Generating a new component

To simplify the above process, you can use generate a new component with turbo.

Run

turbo gen component

to generate a new component template. The generator will add or modify the following files:

>>> Changes made:
  • /packages/components/src/[component-name]/[component-name].tsx (add)
  • /packages/components/src/[component-name]/index.tsx (add)
  • /packages/components/src/[component-name]/stories/[component-name].stories.tsx (add)
  • /packages/components/src/index.ts (modify)
  • /packages/theme/src/components/[component-name].ts (add)
  • /packages/theme/src/components/index.ts (modify)

Storybook

Storybook provides us with an interactive UI playground for our components. This allows us to preview our components in the browser and instantly see changes when developing locally. This example preconfigures Storybook to:

• Use Vite to bundle stories instantly (in milliseconds)
• Automatically find any stories with the *.stories.* file pattern
• Support using module path aliases like @opengovsg/oui for imports
• Write MDX for component documentation pages

For example, here's the included Story for our Button component:

import { buttonStyles } from "@opengovsg/oui-theme";
import type { Meta, StoryObj } from "@storybook/react-vite";

import type { ButtonProps } from "../button";
import { Button } from "../button";

export default {
  title: "Components/Button",
  component: Button,
  // Rest omitted for brevity
} as Meta<typeof Button>;

type Story = StoryObj<typeof Button>;

export const Default: Story = {};

export const IsDisabled: Story = {
  args: {
    isDisabled: true,
  },
};

@oui/storybook includes these Storybook scripts:

• pnpm dev: Starts Storybook in dev mode with hot reloading at localhost:6006
• pnpm build: Builds the Storybook UI and generates the static HTML files
• pnpm preview-storybook: Starts a local server to view the generated Storybook UI

Versioning & Publishing Packages

TODO: Verify and cleanup this section

This example uses Changesets to manage versions, create changelogs, and publish to npm. It's preconfigured so you can start publishing packages immediately.

You'll need to set up OIDC publishing on npmjs with GitHub Actions. Read more about npm trusted publishing here. It's also worth installing the Changesets bot on your repository.

Generating the Changelog

To generate your changelog, run pnpm changeset locally:

1. Which packages would you like to include? – This shows which packages and changed and which have remained the same. By default, no packages are included. Press space to select the packages you want to include in the changeset.
2. Which packages should have a major bump? – Press space to select the packages you want to bump versions for.
3. If doing the first major version, confirm you want to release.
4. Write a summary for the changes.
5. Confirm the changeset looks as expected.
6. A new Markdown file will be created in the changeset folder with the summary and a list of the packages included.

Releasing

TODO: Verify and cleanup this section