Storybook
Living component documentation. Current stable: 10.6.x (10.6.0 on September 2 2026, 10.6.5 on October 27; v11 in alpha). Storybook 10.3 (March-April 2026) delivered an MCP addon (Dev and Test tools for any project, Docs tool for React, Angular and Vue), A11y overhaul (2728→1249 violations, -54%), CSF Factories Preview (auto Component Manifest), Vitest addon. Brad Frost / Dominic Nguyen 2026: *Storybook is your design system's API for AI*.
Strengths
- Living documentation: components testable in isolation in the browser
- Native interaction tests (play functions), visual and behavioral tests combined
- Storybook 9: native Vitest integration, no separate jest needed
- Args controls: test all variants without changing code
Limitations
- Heavy initial config, .storybook/, addons, provider wrappers to configure
- Maintaining stories time-consuming when component API changes frequently
- Chromatic (visual regression) paid beyond one project, cost scales fast
Best for
- Internal design systems with multiple consumers
- Open-source UI libraries needing interactive documentation