Cloudflare Kumo
Cloudflare's React component library for modern web apps: accessible components built on Base UI, with package imports, granular imports, CLI docs, and Figma/token tooling.
Routing Summary
Use Kumo when a React product wants Cloudflare-flavored app components with Base UI accessibility and CLI-readable docs. It fits dense dashboards, infrastructure tools, admin surfaces, and operational workflows better than decorative component galleries.
What it is
Kumo is Cloudflare's component library for React apps. Its README frames the value as accessible, design-system-compliant UI built on Base UI: keyboard navigation, focus management, and ARIA behavior are handled by the underlying primitives. It ships @cloudflare/kumo, CSS imports, granular component imports, primitive re-exports, a docs CLI, and a Figma plugin path.
This makes it useful in Kevin's stack as a serious component source, especially when the app wants an accessible app-product library with explicit docs a coding agent can query from the shell.
Version Snapshot
| Field | Snapshot |
|---|---|
| Repo | cloudflare/kumo |
| Package | @cloudflare/kumo@2.6.0 |
| Release | @cloudflare/kumo@2.6.0, published 2026-06-22 |
| License | MIT |
| Repo status | 2,623 stars / 141 forks / 55 open issues as of 2026-07-04 |
| Last repo push checked | 2026-07-02 |
| Docs | https://kumo-ui.com |
Source: GitHub API, npm registry, Kumo README, 2026-07-04
The reviewed X artifact shows the button polish direction: same basic button sizing and labels, but the "after" state adds a stronger border, subtle gradient/depth, and more tactile pressed-surface treatment for primary and destructive buttons. Treat this as component-quality evidence, not as a command to over-style every product button. Source: X/@nandafyi image artifact, 2026-06-19
Install Shape
pnpm add @cloudflare/kumo
pnpm add react react-dom @phosphor-icons/react
import { Button, Input, Dialog } from "@cloudflare/kumo";
import "@cloudflare/kumo/styles";
Kumo also supports granular imports such as @cloudflare/kumo/components/button and CLI docs:
npx @cloudflare/kumo ls
npx @cloudflare/kumo doc Button
npx @cloudflare/kumo docs
Routing
| Need | Route |
|---|---|
| Accessible React primitives with Cloudflare-flavored app components | Kumo |
| Copy-owned Tailwind/Radix component system | Shadcn UI Ecosystem |
| Fully agent-ready design system with themes/templates/CLI | Astryx Design System |
| Low-level behavior only | Base UI / Radix UI |
Agent Rules
- Prefer the CLI docs over guessing prop names.
- Do not mix Kumo and shadcn variants for the same primitive family in one view.
- Check peer dependencies before copying examples.
- Retokenize color, radius, spacing, typography, and icon set to the host product.
- Treat the X bookmark about button improvements as a visual QA signal, not the version authority.
Timeline
- 2026-07-07 | Cross-linked Base UI after promoting Base UI into the component-library source shelf. Source: User request, 2026-07-07
- 2026-06-29 | Promoted Kumo into the component-source shelf with package/release snapshot and CLI routing. Source: User request, 2026-06-29; GitHub
cloudflare/kumo; npm@cloudflare/kumo - 2026-06-19 | Kumo button-improvement bookmark entered the X bookmark corpus as a visual component-quality signal. Source: X/@nandafyi, 2026-06-19
- 2026-07-04 | Repaired and reviewed the local Kumo button artifact; refreshed source snapshot at
@cloudflare/kumo@2.6.0, repo HEAD6232d34b, 2,623 stars, 141 forks, and 55 open issues. Source: X/@nandafyi image artifact; npm/GitHub checks, 2026-07-04