Storybook is a free and open-source frontend workshop for building, documenting and testing UI components in isolation. It runs alongside a project and renders every component state as a story, so you can develop screens that are hard to reach in the running application – error states, loading states, edge-case data – without mocking up a whole page. Thousands of teams use it as the shared reference for a design system, and it works with React, Vue, Angular, Svelte, Web Components, Ember and React Native.

Key features

• Isolated component canvas with a browsable sidebar tree of stories, grouped by component and section
• Controls addon for editing props live and exercising every variant without touching code
• Docs addon that renders Markdown and MDX documentation next to the components it describes
• Rich addon ecosystem for accessibility checks, viewport and theme switching, mock data and actions logging
• Built-in test runner plus interaction, visual and accessibility testing built on portable stories
• Framework-agnostic: one workshop covers several frameworks and versions in a monorepo
• Static export of the whole workshop, published as a shareable component library for designers and reviewers
• CLI scaffolding (npx storybook@latest init) that detects the project framework and configures the toolchain

How it fits a workflow

Storybook runs on the developer machine and in CI as an ordinary Node.js dependency, either from the project or from a container image in the pipeline. Its static build can be deployed to any static host, which makes the component library reviewable by people outside the repository. It is not a runtime dependency of the shipped application: nothing from Storybook reaches production bundles.

Licence

MIT – free software, no feature gating. The optional hosted companion service Chromatic (visual regression and review) is proprietary and paid, but the Storybook tool itself is complete and self-hostable as an npm package or Docker image.

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