Expo Dom Agent Skill

Framework (OSS). Use Expo DOM components to run web code in a webview on native and as-is on web. Migrate web code to native incrementally. For the end-to-end migration of a whole web app, use the expo-web-to-native skill.

3k tokens

context cost

the whole folder, loaded on every use

files

instructions only

copies elsewhere

how many repositories repackaged it

2356

stars on the repo

on the repository, not the skill itself

Install

one command, takes just this skill from the repository

npx skills add https://github.com/expo/skills --skill expo-dom

What comes with it

371 bytes besides the instruction

agents/openai.yaml

The instruction itself

18 sections, as written by the author

What are DOM Components?

DOM components allow web code to run verbatim in a webview on native platforms while rendering as-is on web. This enables using web-only libraries like recharts, react-syntax-highlighter, or any React web library in your Expo app without modification.

When to Use DOM Components

Use DOM components when you need:

Web-only libraries — Charts (recharts, chart.js), syntax highlighters, rich text editors, or any library that depends on DOM APIs
Migrating web code — Bring existing React web components to native without rewriting
Complex HTML/CSS layouts — When CSS features aren't available in React Native
iframes or embeds — Embedding external content that requires a browser context
Canvas or WebGL — Web graphics APIs not available natively

When NOT to Use DOM Components

Avoid DOM components when:

Native performance is critical — Webviews add overhead
Simple UI — React Native components are more efficient for basic layouts
Deep native integration — Use local modules instead for native APIs
Layout routes — _layout files cannot be DOM components

Basic DOM Component

Create a new file with the 'use dom'; directive at the top:

// components/WebChart.tsx
"use dom";

export default function WebChart({
  data,
}: {
  data: number[];
  dom: import("expo/dom").DOMProps;
}) {
  return (
    <div style={{ padding: 20 }}>
      <h2>Chart Data</h2>
      <ul>
        {data.map((value, i) => (
          <li key={i}>{value}</li>
        ))}
      </ul>
    </div>
  );
}

Rules for DOM Components

Must have 'use dom'; directive at the top of the file
Single default export — One React component per file
Own file — Cannot be defined inline or combined with native components
Serializable props only — Strings, numbers, booleans, arrays, plain objects
Include CSS in the component file — DOM components run in isolated context

The `dom` Prop

Every DOM component receives a special dom prop for webview configuration. Always type it in your props:

"use dom";

interface Props {
  content: string;
  dom: import("expo/dom").DOMProps;
}

export default function MyComponent({ content }: Props) {
  return <div>{content}</div>;
}

Common `dom` Prop Options

// Disable body scrolling
<DOMComponent dom={{ scrollEnabled: false }} />

// Flow under the notch (disable safe area insets)
<DOMComponent dom={{ contentInsetAdjustmentBehavior: "never" }} />

// Control size manually
<DOMComponent dom={{ style: { width: 300, height: 400 } }} />

// Combine options
<DOMComponent
  dom={{
    scrollEnabled: false,
    contentInsetAdjustmentBehavior: "never",
    style: { width: '100%', height: 500 }
  }}
/>

Exposing Native Actions to the Webview

Pass async functions as props to expose native functionality to the DOM component:

// app/index.tsx (native)
import { Alert } from "react-native";
import DOMComponent from "@/components/dom-component";

export default function Screen() {
  return (
    <DOMComponent
      showAlert={async (message: string) => {
        Alert.alert("From Web", message);
      }}
      saveData={async (data: { name: string; value: number }) => {
        // Save to native storage, database, etc.
        console.log("Saving:", data);
        return { success: true };
      }}
    />
  );
}

// components/dom-component.tsx
"use dom";

interface Props {
  showAlert: (message: string) => Promise<void>;
  saveData: (data: {
    name: string;
    value: number;
  }) => Promise<{ success: boolean }>;
  dom?: import("expo/dom").DOMProps;
}

export default function DOMComponent({ showAlert, saveData }: Props) {
  const handleClick = async () => {
    await showAlert("Hello from the webview!");
    const result = await saveData({ name: "test", value: 42 });
    console.log("Save result:", result);
  };

  return <button onClick={handleClick}>Trigger Native Action</button>;
}

Using Web Libraries

DOM components can use any web library:

// components/syntax-highlight.tsx
"use dom";

import SyntaxHighlighter from "react-syntax-highlighter";
import { docco } from "react-syntax-highlighter/dist/esm/styles/hljs";

interface Props {
  code: string;
  language: string;
  dom?: import("expo/dom").DOMProps;
}

export default function SyntaxHighlight({ code, language }: Props) {
  return (
    <SyntaxHighlighter language={language} style={docco}>
      {code}
    </SyntaxHighlighter>
  );
}

// components/chart.tsx
"use dom";

import {
  LineChart,
  Line,
  XAxis,
  YAxis,
  CartesianGrid,
  Tooltip,
} from "recharts";

interface Props {
  data: Array<{ name: string; value: number }>;
  dom: import("expo/dom").DOMProps;
}

export default function Chart({ data }: Props) {
  return (
    <LineChart width={400} height={300} data={data}>
      <CartesianGrid strokeDasharray="3 3" />
      <XAxis dataKey="name" />
      <YAxis />
      <Tooltip />
      <Line type="monotone" dataKey="value" stroke="#8884d8" />
    </LineChart>
  );
}

CSS in DOM Components

CSS imports must be in the DOM component file since they run in isolated context:

// components/styled-component.tsx
"use dom";

import "@/styles.css"; // CSS file in same directory

export default function StyledComponent({
  dom,
}: {
  dom: import("expo/dom").DOMProps;
}) {
  return (
    <div className="container">
      <h1 className="title">Styled Content</h1>
    </div>
  );
}

Or use inline styles / CSS-in-JS:

"use dom";

const styles = {
  container: {
    padding: 20,
    backgroundColor: "#f0f0f0",
  },
  title: {
    fontSize: 24,
    color: "#333",
  },
};

export default function StyledComponent({
  dom,
}: {
  dom: import("expo/dom").DOMProps;
}) {
  return (
    <div style={styles.container}>
      <h1 style={styles.title}>Styled Content</h1>
    </div>
  );
}

Expo Router in DOM Components

The expo-router <Link /> component and router API work inside DOM components:

"use dom";

import { Link, useRouter } from "expo-router";

export default function Navigation({
  dom,
}: {
  dom: import("expo/dom").DOMProps;
}) {
  const router = useRouter();

  return (
    <nav>
      <Link href="/about">About</Link>
      <button onClick={() => router.push("/settings")}>Settings</button>
    </nav>
  );
}

Router APIs That Require Props

These hooks don't work directly in DOM components because they need synchronous access to native routing state:

useLocalSearchParams()
useGlobalSearchParams()
usePathname()
useSegments()
useRootNavigation()
useRootNavigationState()

Solution: Read these values in the native parent and pass as props:

// app/[id].tsx (native)
import { useLocalSearchParams, usePathname } from "expo-router";
import DOMComponent from "@/components/dom-component";

export default function Screen() {
  const { id } = useLocalSearchParams();
  const pathname = usePathname();

  return <DOMComponent id={id as string} pathname={pathname} />;
}

// components/dom-component.tsx
"use dom";

interface Props {
  id: string;
  pathname: string;
  dom?: import("expo/dom").DOMProps;
}

export default function DOMComponent({ id, pathname }: Props) {
  return (
    <div>
      <p>Current ID: {id}</p>
      <p>Current Path: {pathname}</p>
    </div>
  );
}

Detecting DOM Environment

Check if code is running in a DOM component:

"use dom";

import { IS_DOM } from "expo/dom";

export default function Component({
  dom,
}: {
  dom?: import("expo/dom").DOMProps;
}) {
  return <div>{IS_DOM ? "Running in DOM component" : "Running natively"}</div>;
}

Assets

Prefer requiring assets instead of using the public directory:

"use dom";

// Good - bundled with the component
const logo = require("../assets/logo.png");

export default function Component({
  dom,
}: {
  dom: import("expo/dom").DOMProps;
}) {
  return <img src={logo} alt="Logo" />;
}

Usage from Native Components

Import and use DOM components like regular components:

// app/index.tsx
import { View, Text } from "react-native";
import WebChart from "@/components/web-chart";
import CodeBlock from "@/components/code-block";

export default function HomeScreen() {
  return (
    <View style={{ flex: 1 }}>
      <Text>Native content above</Text>

      <WebChart data={[10, 20, 30, 40, 50]} dom={{ style: { height: 300 } }} />

      <CodeBlock
        code="const x = 1;"
        language="javascript"
        dom={{ scrollEnabled: true }}
      />

      <Text>Native content below</Text>
    </View>
  );
}

Platform Behavior

| Platform | Behavior |

| -------- | ----------------------------------- |

| iOS | Rendered in WKWebView |

| Android | Rendered in WebView |

| Web | Rendered as-is (no webview wrapper) |

On web, the dom prop is ignored since no webview is needed.

Tips

DOM components hot reload during development
Keep DOM components focused — don't put entire screens in webviews
Use native components for navigation chrome, DOM components for specialized content
Test on all platforms — web rendering may differ slightly from native webviews
Large DOM components may impact performance — profile if needed
The webview has its own JavaScript context — cannot directly share state with native

Submitting Feedback

If you encounter errors, misleading or outdated information in this skill, report it so Expo can improve:

npx --yes submit-expo-feedback@latest --category skills --subject "expo-dom" "<actionable feedback>"

Only submit when you have something specific and actionable to report. Include as much relevant context as possible.

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How to use it

Copy the folder

Take expo/expo-dom from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.

Install what it needs

The instructions reference npx. Without those the skill loads but fails at the first command.

Expo Dom Agent Skill

Install

What comes with it

The instruction itself

What are DOM Components?

When to Use DOM Components

When NOT to Use DOM Components

Basic DOM Component

Rules for DOM Components

The dom Prop

Common dom Prop Options

Exposing Native Actions to the Webview

Using Web Libraries

CSS in DOM Components

Expo Router in DOM Components

Router APIs That Require Props

Detecting DOM Environment

Assets

Usage from Native Components

Platform Behavior

Tips

Submitting Feedback

Other skills for the same job

How to use it

The `dom` Prop

Common `dom` Prop Options