Ultra Fast, Zero Runtime, Utility-First CSS-in-JS

Documentation

🐻‍❄️ Kuma UI is a utility-first, zero-runtime CSS-in-JS library that offers an outstanding developer experience and optimized performance.

Features

🔥   Blazing-fast performance with zero-runtime CSS extraction

🦄   Build-time CSS generation

🌳   Responsive design with breakpoints and media queries

🎨   Utility-first approach for rapid UI development

👋   Support for pseudo-classes and pseudo-elements

🔬   Experimental support for Next.js 13.4 App router & React server components(RSC).

Installation

npm install -D @kuma-ui/core

or

yarn add @kuma-ui/core -D

Usage

styled API

The styled API works just like styled-components or Emotion, allowing you to create styled React components using tagged template literals. This makes it a familiar and comfortable choice for developers who have worked with these libraries.

import { styled } from "@kuma-ui/core";

const Box = styled("div")`
  position: relative;
  &:hover {
    background-color: rgba(0, 0, 255, 0.5);
  }
  @media (max-width: 768px) {
    flex-direction: column;
  }
`;

// Then use it like so:
<Box>Hello, world!</Box>;

k object

The k object is a key part of Kuma UI's API. It provides pre-styled HTML elements that you can use as components in your application. These elements can be styled using utility props for inline styling. The utility props are type-safe and make it easy to write responsive styles.

import { k } from "@kuma-ui/core";

function App() {
  return (
    <k.div p={[4, 8]} m="2px" _hover={{ flexDir: "row" }}>
      hello world
    </k.div>
  );
}

css function

The css function is another way to style your components. It takes an object of styles and returns a string of hashed classNames that you can apply to your component using the className prop.

import { css } from "@kuma-ui/core";

const styles = css({ color: "red", fontSize: "24px" });

function App() {
  return <div className={styles}>Hello, world!</div>;
}

Setup

Next.js

yarn add @kuma-ui/next-plugin -D

Pages Directory Version

next.config.js

const { withKumaUI } = require("@kuma-ui/next-plugin");

/** @type {import('next').NextConfig} */
const nextConfig = {
  reactStrictMode: true,
};

module.exports = withKumaUI(nextConfig);

App Router Version (Experimental)

next.config.js

const { withKumaUI } = require("@kuma-ui/next-plugin");

/** @type {import('next').NextConfig} */
const nextConfig = {
  reactStrictMode: true,
  experimental: {
    appDir: true
  }
};

module.exports = withKumaUI(nextConfig);

Vite

yarn add @kuma-ui/vite -D

vite.config.ts

import { defineConfig } from "vite";
import react from "@vitejs/plugin-react";
import KumaUI from "@kuma-ui/vite";

// https://vitejs.dev/config/
export default defineConfig({
  plugins: [
    react({
      jsxRuntime: "classic",
    }),
    KumaUI(),
  ],
});

Responsive Design

Kuma UI supports responsive design. Use arrays to specify different styles for different viewport widths. For example, <k.div fontSize={[16, 24]} /> changes the font size from 16px to 24px based on the window size.

Define the breakpoints in your config file:

import kumaUI from "@kuma-ui/vite";

kumaUI({
  breakpoints: { sm: "400px", md: "700px" },
});

Roadmap

Our ultimate goal is to develop a zero-runtime headless component library. We're currently focusing on enhancing the core and expanding our range of components. We aim to create a unique library that allows users to pass style props, operates with zero runtime, and remains accessible. In the future, we plan to introduce a kuma.config.js that allows users to define their own variants, making Kuma UI a go-to tool for creating design systems with high performance.

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests with any improvements or suggestions.

Adding a changeset

Don't forget to include a changeset as well, by running this command at the root of the project:

pnpm changeset

License

MIT