WorkOS · Design system breakdown
Unstyled, accessible primitives that quietly power half of modern React.
Modulz built Radix Primitives starting in 2019 to ship unstyled, accessible component primitives for React. WorkOS acquired Modulz in 2022 and continues to maintain Radix as open source. shadcn/ui, Vercel's design system, and many internal design systems build on Radix Primitives.
WorkOS-supported, open source under MIT. Active maintainer team with a measured release cadence. Radix Themes (a styled layer) ships alongside the unstyled Primitives for teams that want both.
| Token | Value | Role |
|---|---|---|
| Primitives | Unstyled | No tokens — bring your own theme |
| Radix Colors gray.1 | Theme-defined | Lightest gray (Radix Colors package) |
| Radix Colors blue.9 | Theme-defined | Solid brand color step |
| Radix Themes accent.9 | Theme-defined | Primary action (Themes layer) |
| Radix Themes radius | 1–6 scale | Configurable global radius |
| Radix Themes scaling | 0.9–1.1 | Global density factor |
Token names and values are illustrative — refer to the system's official tokens reference for the canonical, current set.
If you're evaluating this system
Use Radix Primitives whenever you're building your own component library — they handle the hard parts (accessibility, focus, keyboard) so you can focus on visual design. If you don't want to think about styling at all, use Radix Themes or shadcn/ui (which wraps Radix with Tailwind).
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