Zag
Finite state machines for accessible JavaScript components
- Write once, use everywhere 🦄: The component interactions are modelled in a framework agnostic way. We provide
adapters for JS frameworks like React, Solid, or Vue.
- Focus on accessibility ♿️: Zag is built with accessibility in mind. We handle many details related to keyboard
interactions, focus management, aria roles and attributes.
- Headless ✨: The machine APIs are completely unstyled and gives you the control to use any styling solution you
prefer.
- Powered by state machines 🌳: Zag is built on top of the latest ideas in Statecharts. We don't follow the SCXML
specifications, but we've created an API that we think will help us build more complex components fast.
Documentation
To see the documentation, visit zagjs.com/
Releases
For changelog, Check CHANGELOG.md
Problem
With the rise of design systems and component-driven development, there's an endless re-implementation of common
component patterns (Tabs, Menu, Modal, etc.) in multiple frameworks.
Most of these implementations seem to be fairly similar in spirit, the differences being around the reactivity and
effects systems for the framework (e.g. useState, useEffect in React.js). Framework specific solutions tend to grow
in complexity over time and often become hard to understand, debug, improve or test.
Solution
Zag is a JavaScript API that implements common component patterns using the state machine methodology.
Installation
npm i --save @zag-js/{component}
# or
yarn add @zag-js/{component}
{component} represents any component machine like dialog (@zag-js/dialog), tooltip (@zag-js/tooltip) , etc.
For framework specific solutions, we provide simple wrappers to help you consume the component state machines.
- ⚛️
@zag-js/react - React hooks for consuming machines in React applications
- 💚
@zag-js/vue - Vue composition for consuming machines in Vue applications
- 🎷
@zag-js/solid - Solid.js utilities for consuming machines in Solid.js applications
Usage
import { normalizeProps, useMachine } from "@zag-js/react"
import * as toggle from "@zag-js/toggle-group"
import { useId } from "react"
export function ToggleGroup() {
const [state, send] = useMachine(toggle.machine({ id: useId() }))
const api = toggle.connect(state, send, normalizeProps)
return (
<div {...api.getRootProps()}>
<button {...api.getItemProps({ value: "bold" })}>B</button>
<button {...api.getItemProps({ value: "italic" })}>I</button>
<button {...api.getItemProps({ value: "underline" })}>U</button>
</div>
)
}
Guiding Principles
- All component machines and tests are modelled according to the
WAI-ARIA authoring practices
- Write end-to-end tests for every component based on the WAI-ARIA spec. Regardless of the framework, users expect
component patterns to work the same way!
- All machines should be light-weight, simple, and easy to understand. Avoid using complex machine concepts like spawn,
nested states, etc.
Fun Facts
Zag means to take a sharp change in direction. This clearly describes our approach of using state machines to
power the logic behind UI components.
Teasers
-
When you see someone using classic react, vue or solid to build an interactive UI component that exists in Zag, tell
them to "zag it!" ⚡️
-
Anyone using Zag will be called a "zagger" 💥
-
The feeling you get when you use Zag will be called "zagadat!" 🚀
-
The Zag community will be called "zag nation" 🔥
Commands
Build commands
Our build is managed with esbuild and turborepo to provide fast, concurrent builds across the packages.
build : Build the CJS, ESM and DTS files. This is the actual production build that we run in the CI.
Examples
Since zag is framework agnostic, we need a way to test it within a framework. The examples/ directory includes starter
projects for the frameworks we support.
start-react : Starts the Next.js TypeScript projectstart-vue : Starts the Vue 3 TypeScript projectstart-solid : Starts the Solid TypeScript project
E2E Tests
We've setup end-to-end tests for every machine we built. We use Playwright for testing and we
ensure that the component works the same way regardless of the framework.
e2e-react : Starts the E2E tests for the React projecte2e-vue : Starts the E2E tests for the Vue projecte2e-solid : Starts the E2E tests for the Solid project
Contributing new machines/features
generate-machine : Generates a new machine package in the packages/ directory. It sets up the required files and
structure for new machine.generate-util : Generates a new utility package in the packages/utilities directory.
Other commands
test : Run the tests for all packageslint : Lint all packages
Website
start-website: Starts the website
Inspirations
Contributions
Looking to contribute? Look for the Good First Issue label.
🐛 Bugs
Please file an issue for bugs, missing documentation, or unexpected behavior.
💡 Feature Requests
Please file an issue to suggest new features. Vote on feature requests by adding a 👍. This helps maintainers prioritize
what to work on.
License
MIT © Segun Adebayo
