Astro

Astro is a flexible meta-framework that accommodates a wide range of tools and integrations, enabling you to leverage numerous ecosystems.

It also allows you to write components using your favorite UI framework (or no framework at all) and renders your pages to static HTML at build time, or dynamically on the server using Server-Side Rendering (SSR).

This results in a fast, SEO-friendly output that can be deployed to any static hosting environment or server.

For more details on the integration and to view the source code, check out the QwikDev Astro Integration on GitHub.

Astro instead of Qwik City

When integrating Astro with Qwik, it's important to note that Qwik City APIs are not compatible with Astro.

Astro is a meta-framework that provides its own set of APIs and features for handling these concerns. These include:

routing
pages
layouts
data fetching
server-side rendering (SSR)

Therefore, when integrating Qwik with Astro, you should use Astro's APIs and features instead of Qwik City's APIs. This will ensure that your Qwik components work correctly within the Astro environment. For more information, see the Astro documentation.

@qwikdev/astro 💜

This integration leverages the power of Resumability inside of Astro, using Qwik components.

Installation

There are two methods to add the integration. Let's begin with the easiest one!

The Astro CLI

Astro comes with a command-line tool for incorporating built-in integrations: astro add. This command will:

Optionally install all required dependencies and peer dependencies
Optionally modify your astro.config.* file to apply the integration

To install @qwikdev/astro, run the following from your project directory and follow the prompts:

# Using NPM
npx astro add @qwikdev/astro
 
# Using Yarn
yarn astro add @qwikdev/astro
 
# Using PNPM
pnpm astro add @qwikdev/astro

Setting up the TypeScript Config

The integration needs the following in tsconfig.json for typescript to recognize Qwik's JSX types.

"compilerOptions": {
  "jsx": "react-jsx",
  "jsxImportSource": "@builder.io/qwik"
}

If you face any issues, please post them on Github and attempt the manual installation below.

Manual Installation

First, install the @qwikdev/astro integration like so:

npm install @qwikdev/astro

Typically, package managers install peer dependencies. However, if you get a Cannot find package '@builder.io/qwik' warning when starting Astro, install Qwik.

npm install @builder.io/qwik

Now, add the integration to your astro.config.* file using the integrations property:

  // astro.config.mjs
  import { defineConfig } from 'astro/config';
+ import qwikdev from '@qwikdev/astro';
 
  export default defineConfig({
    // ...
    integrations: [qwikdev()],
    //             ^^^^^
  });

If you are also using other integrations like react() or preact(), you will need to put qwikdev() before them in the list. Or you will have Not a QRL errors. Something like this: integrations: [qwikdev(), react(), preact()].

Qwik does not hydrate, it is fundamentally different

Astro is popular for its partial hydration approach, whereas Qwik does not require hydration.

Adding a Qwik component

In other UI frameworks, a hydration directive would be needed for interactivity, such as client:only or client:load. These are not needed with Qwik, because there is no hydration!

When using Qwik inside a meta framework like Astro or Qwik City, components are loaded on the server, prefetched in a separate thread, and "resumed" on the client.

For example here's how we create a counter component in Qwik (e.g. at src/components/counter.tsx).

import { component$, useSignal } from "@builder.io/qwik";
 
export const Counter = component$(() => {
  const counter = useSignal(0);
 
  return <button onClick$={() => counter.value++}>{counter.value}</button>;
});

It can be consumed in our index.astro page like so:

    ---
    import { Counter } from "../components/counter";
    ---
 
    <html lang="en">
        <head>
            <meta charset="utf-8" />
            <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
            <meta name="viewport" content="width=device-width" />
            <meta name="generator" content={Astro.generator} />
            <title>Astro</title>
        </head>
        <body>
            <h1>Astro.js - Qwik</h1>
            /* no hydration directive! */
            <Counter />
        </body>
    </html>

Starts fast, stays fast

One of Astro's key features is Zero JS, by default. Unfortunately, after adding a JavaScript framework, and any subsequent components this is usually not the case.

If we want to introduce interactivity with a framework such as React, Vue, Svelte, etc., the framework runtime is then introduced. The number of components added to the page also increases linearly O(n) with the amount of JavaScript.

Astro + Qwik

Qwik builds on top of Astro's Zero JS, by defaut principle and then some. Thanks to resumability, the components are not executed unless resumed. Even with interactivity, the framework is also not executed until it needs to be. It is O(1) constant, and zero effort on the developer.

Instead, upon page load, a tiny 1kb minified piece of JavaScript, known as the Qwikloader, downloads the rest of the application as needed.

Fine-grained lazy loading

Hydration forces your hand to eagerly execute code. It's not a problem with components that are outside of the tree, such as modals, but it must exhaustively check each component in the render tree just in case.

Qwik works exceptionally well in Astro due to Resumability and its ability to lazy load code in a fine-grained manner. Especially for marketing sites, blogs, and content oriented sites with many components.

Instant interactivity

As of @qwikdev/astro v0.4, we have added support for Speculative Module Fetching in Astro.

This enables instant interactivity for your Qwik components. Speculative module fetching will prefetch the application bundles in the background of a service worker, so that when needed, the code is already present in the browser cache.

You should be able to use Qwik insights out of the box!

Containers vs. Islands

While Astro generally adopts an islands architecture with other frameworks, Qwik uses a different strategy known as Qwik containers. Despite the differences in approach, both share similar limitations.

In the DOM, you may notice there aren't any <astro-island> custom elements, this is because to Astro, Qwik looks like static data.

This is because in Qwik, the handlers themselves are the roots / entrypoints of the application.

Communicating across containers

One common limitation is trying to pass state into another island or container.

Sharing state is crucial in modern web development. The question is, how can we achieve this when state needs to be shared across different containers or islands?

Why not use global signals or nanostores?

Other frameworks with Astro address this by using nano stores, or global signals.

While you may see all of your tests passing, and the application working as expected, we do not recommend using nanostores or global signals. They can lead to some unexpected behavior in an SSR context.

For example, in Solid's tutorial the following is mentioned:

While it is possible to use global state and computations, Context is sometimes a better solution. Additionally, it is important to note that global state should not be used in SSR (server side rendering) solutions, such as Solid Start. On the server, global state is shared across requests, and the lack of data isolation can (and will) lead to bugs, memory leaks and has security implications. It is recommended that application state should always be provided via context instead of relying on global.

Custom Events

In Qwik, it was a design decision to not include global signal state.

Instead, we recommend the use of custom events, which offer several advantages:

Performance (avoid unnecessary state synchronization)
Does not wake up the framework on page load
Micro Frontend (MFE) Support
Different versions can exist on the page
Event Driven
Decoupled

This example shows how custom events can be used throughout your application. Pay attention to counter.tsx, random-island.tsx, and our index.astro page.

Using multiple JSX frameworks

To use multiple JSX frameworks like Qwik, React, Preact, or Solid in Astro, you need to set up rules for which files each framework should handle.

For example, you can place all Qwik components in a folder named qwik. Then, configure Astro to process any file within this folder using the Qwik integration.

import { defineConfig } from "astro/config";
import qwik from "@qwikdev/astro";
import react from "@astrojs/react";
 
export default defineConfig({
  integrations: [
    qwik({ include: "**/qwik/*" }),
    react({ include: "**/react/*" }),
    solid({ include: "**/solid/*" }),
  ],
});

Above we're using the Qwik, React, and Solid integrations in the same Astro project.

If we look at the first integration, it's going to look for any file in the qwik folder and use Qwik for any file in this folder.

For simplicity, consider grouping common framework components in the same folder (like /components/react/ and /components/qwik/). However, this is optional.

Qwik React

If you're using React, we suggest using the @builder.io/qwik-react integration. It's a drop-in replacement for @astrojs/react, and allows a seamless transition to Qwik.

import { defineConfig } from "astro/config";
 
import qwikdev from "@qwikdev/astro";
import { qwikReact } from "@builder.io/qwik-react/vite";
 
// https://astro.build/config
export default defineConfig({
  integrations: [qwikdev()],
  vite: {
    plugins: [qwikReact()],
  },
});

With Qwik-React, we can "qwikify" our React components, and use them in our Qwik application, even nesting Qwik and React components outside of an Astro file!

You do not need to specify an include property with qwikReact.

Here's an example of a React component with the qwik-react integration.

/** @jsxImportSource react */
import { qwikify$ } from "@builder.io/qwik-react";
import { useState } from "react";
 
const ReactCounter = () => {
  const [count, setCount] = useState(0);
 
  return <button onClick={() => setCount(count + 1)}>React {count}</button>;
};
 
// "Qwikified" React component
export const QReactCounter = qwikify$(ReactCounter);

After creating our counter, it can be consumed in our index.astro file.

<QReactCounter qwik:visible />

Notice that in .astro files we use a qwik: hydration directive prefix, this is to prevent a conflict with Astro's hydration directives that are provided out of the box.

You can also use the client:* prefix, but only in tsx files. You can find a list of directives in Adding Interactivity section of the Qwik docs.

Qwik React components still have hydration, thus it is recommended to use Qwik-React as a migration strategy to resumable components.

jsxImportSource

Unfortunately, TypeScript can only have one jsxImportSource default. If you're using React, Solid, or Preact's Astro integration in your Astro app alongside, please override each component's import source.

If you're using @astrojs/react, you can use qwik-react instead. The proper configuration will be supported out of the box.

/** @jsxImportSource react */
import { useState } from "react";
 
export const ReactCounter = () => {
  const [count, setCount] = useState(0);
  return <button onClick={() => setCount(count + 1)}>{count}</button>;
};

Solid JS for example, is:

/** @jsxImportSource solid-js */

Preact for example, is:

/** @jsxImportSource preact */

Named Slots

For named slots within Astro, instead of adding q:slot on the markup, add slot instead.

my-slot-comp.tsx

import { Slot, component$, useSignal } from "@builder.io/qwik";
 
export const MySlotComp = component$<{ initial: number }>((props) => {
  return (
    <>
      <Slot name="test" />
    </>
  );
});

index.astro

  <MySlotComp>
    <div slot="test">Content inside the slot named test!</div>
  </MySlotComp>

Default slots work as expected in their Qwik City counterpart.

Community Guides

Paul Scanlon shows a hands-on look at using Qwik in Astro over React and Vanilla JS.
Rishi Raj Jain has written an awesome guide on setting up Qwik with Astro's Vercel SSR Adapter.
Paul Scanlon explores using Qwik as a React alternative in Astro.

Videos

Watch Jason & Steve [discuss the Qwik Astro integration] on the LWJ show.
Awesome's Qwik + Astro video goes into how Astro just got even faster.

Contributing

We'd love for you to contribute! Start by reading our Contributing Guide. It's got all the info you need to get involved, including an in-depth section on how the integration works under the hood.

There's also a qwik-astro channel in the builder.io discord to discuss API changes, possible ideas to the integration, and other cool stuff. 😊

Credits

Special thanks to Matthew and Nate from the Astro core team! This integration would not be possible without their help.

Nate's handles:

Contributors

Thanks to all the contributors who have helped make this documentation better!