Upgrade to Astro v2

This guide will help you migrate from Astro v1 to Astro v2.

Need to upgrade an older project to v1? See our older migration guide.

Upgrade Astro

Update your project’s version of Astro to the latest version using your package manager. If you’re using Astro integrations, please also update those to the latest version.

npm

# Upgrade to Astro v2.x
npm install astro@latest

# Example: upgrade React and Tailwind integrations
npm install @astrojs/react@latest @astrojs/tailwind@latest

pnpm

# Upgrade to Astro v2.x
pnpm add astro@latest

# Example: upgrade React and Tailwind integrations
pnpm add @astrojs/react@latest @astrojs/tailwind@latest

Yarn

# Upgrade to Astro v2.x
yarn add astro@latest

# Example: upgrade React and Tailwind integrations
yarn add @astrojs/react@latest @astrojs/tailwind@latest

Astro v2.0 Breaking Changes

Astro v2.0 includes some breaking changes, as well as the removal of some previously deprecated features. If your project doesn’t work as expected after upgrading to v2.0, check this guide for an overview of all breaking changes and instructions on how to update your codebase.

See the changelog for full release notes.

Removed: Support for Node 14

Node 14 is scheduled to reach its End of Life in April 2023.

Astro v2.0 drops Node 14 support entirely, so that all Astro users can take advantage of Node’s more modern features.

What should I do?

Check that both your development environment and your deployment environment are using Node 16.12.0 or later.

1. Check your local version of Node using:

   node -v

   If your local development environment needs upgrading, install Node.

2. Check your deployment environment’s own documentation to verify that they support Node 16.

   You can specify Node 16.12.0 for your Astro project either in a dashboard configuration setting, or a .nvmrc file.

Reserved: src/content/

Astro v2.0 now includes the Collections API for organizing your Markdown and MDX files into content collections. This API reserves src/content/ as a special folder.

What should I do?

Rename an existing src/content/ folder to avoid conflicts. This folder, if it exists, can now only be used for content collections.

Changed: Astro.site trailing slash

In v1.x, Astro ensured the URL you set as site in astro.config.mjs always had a trailing slash when accessed using Astro.site.

Astro v2.0 no longer modifies the value of site. Astro.site will use the exact value defined, and a trailing slash must be specified if desired.

What should I do?

In astro.config.mjs, add a trailing slash to the URL set in site.

astro.config.mjs

import { defineConfig } from 'astro/config';

export default defineConfig({
  site: 'https://example.com',
  site: 'https://example.com/',
});

Changed: _astro/ folder for build assets

In v1.x, assets were built to various locations, including assets/, chunks/, and to the root of the build output.

Astro v2.0 moves and unifies the location of all build output assets to a new _astro/ folder.

• Directorydist/

  • Directory_astro

    • client.9218e799.js
    • index.df3f880e0.css

You can control this location with the new build.assets configuration option.

What should I do?

Update your deployment platform configuration if it relies on the location of these assets.

Changed: Markdown plugin configuration

Removed: extendDefaultPlugins

In v1.x, Astro used markdown.extendDefaultPlugins to re-enable Astro’s default plugins when adding your own Markdown plugins.

Astro v2.0 removes this configuration option entirely because its behavior is now the default.

Applying remark and rehype plugins in your Markdown configuration no longer disables Astro’s default plugins. GitHub-Flavored Markdown and Smartypants are now applied whether or not custom remarkPlugins or rehypePlugins are configured.

What should I do?

Remove extendDefaultPlugins in your configuration. This is now Astro’s default behavior in v2.0, and you can delete this line without any replacement.

astro.config.mjs

import { defineConfig } from 'astro/config';

export default defineConfig({
  markdown: {
    extendDefaultPlugins,
  }
});

Added: gfm and smartypants

In v1.x, you could choose to disable both of Astro’s default Markdown plugins (GitHub-Flavored Markdown and SmartyPants) by setting markdown.extendDefaultPlugins: false.

Astro v2.0 replaces markdown.extendDefaultPlugins: false with separate Boolean options to individually control each of Astro’s built-in default Markdown plugins. These are enabled by default and can be set to false independently.

What should I do?

Remove extendDefaultPlugins: false and add the flags to disable each plugin individually instead.

• markdown.gfm: false disables GitHub-Flavored Markdown
• markdown.smartypants: false disables SmartyPants

astro.config.mjs

import { defineConfig } from 'astro/config';

export default defineConfig({
  markdown: {
    extendDefaultPlugins: false,
    smartypants: false,
    gfm: false,
  }
});

Changed: MDX plugin configuration

Replaced: extendPlugins changed to extendMarkdownConfig

In v1.x, the MDX integration’s extendPlugins option managed how your MDX files should inherit your Markdown configuration: all your Markdown configuration (markdown), or Astro’s default plugins only (default).

Astro v2.0 replaces the behavior controlled by mdx.extendPlugins with three new, independently-configurable options that are true by default:

• mdx.extendMarkdownConfig to inherit all or none of your Markdown configuration
• mdx.gfm to enable or disable GitHub-Flavored Markdown in MDX
• mdx.smartypants to enable or disable SmartyPants in MDX

What should I do?

Delete extendPlugins: 'markdown' in your configuration. This is now the default behavior.

astro.config.mjs

import { defineConfig } from 'astro/config';
import mdx from '@astrojs/mdx';

export default defineConfig({
  integrations: [
    mdx({
      extendPlugins: 'markdown',
    }),
  ],
});

Replace extendPlugins: 'defaults' with extendMarkdownConfig: false and add the separate options for GitHub-Flavored Markdown and SmartyPants to enable these default plugins individually in MDX.

astro.config.mjs

import { defineConfig } from 'astro/config';
import mdx from '@astrojs/mdx';

export default defineConfig({
  integrations: [
    mdx({
      extendPlugins: 'defaults',
      extendMarkdownConfig: false,
      smartypants: true,
      gfm: true,
    }),
  ],
});

Added: More MDX config options to match Markdown

Astro v2.0 allows you to now individually set every available Markdown configuration option (except drafts) separately in your MDX integration configuration.

astro.config.mjs

import { defineConfig } from 'astro/config';
import mdx from '@astrojs/mdx';

export default defineConfig({
  markdown: {
    remarkPlugins: [remarkPlugin1],
    gfm: true,
  },
  integrations: [
    mdx({
      remarkPlugins: [remarkPlugin2],
      gfm: false,
    })
  ]
});

What should I do?

Revisit your Markdown and MDX configuration and compare your existing config with the new options available.

Changed: Plugin access to frontmatter

In v1.x, remark and rehype plugins did not have access to user frontmatter. Astro merged plugin frontmatter with your file’s frontmatter, without passing the file frontmatter to your plugins.

Astro v2.0 gives remark and rehype plugins access to user frontmatter via frontmatter injection. This allows plugin authors to modify a user’s existing frontmatter, or compute new properties based on other properties.

What should I do?

Check any remark and rehype plugins you have written to see whether their behavior has changed. Note that data.astro.frontmatter is now the complete Markdown or MDX document’s frontmatter, rather than an empty object.

Changed: RSS Configuration

In v1.x, Astro’s RSS package allowed you to use items: import.meta.glob(...) to generate a list of RSS feed items. This usage is now deprecated and will eventually be removed.

Astro v2.0 introduces a pagesGlobToRssItems() wrapper to the items property.

What should I do?

Import, then wrap your existing function containing import.meta.glob() with the pagesGlobToRssItems() helper.

src/pages/rss.xml.js

import rss, {
  pagesGlobToRssItems
} from '@astrojs/rss';

export async function get(context) {
  return rss({
    items: await pagesGlobToRssItems(
      import.meta.glob('./blog/*.{md,mdx}'),
    ),
  });
}

Changed: Svelte IDE support

Astro v2.0 requires a svelte.config.js file in your project if you are using the @astrojs/svelte integration. This is needed to provide IDE autocompletion.

What should I do?

Add a svelte.config.js file to the root of your project:

svelte.config.js

import { vitePreprocess } from '@astrojs/svelte';

export default {
  preprocess: vitePreprocess(),
};

For new users, this file will be added automatically when running astro add svelte.

Removed: legacy.astroFlavoredMarkdown

In v1.0, Astro moved the old Astro-Flavored Markdown (also known as Components in Markdown) to a legacy feature.

Astro v2.0 removes the legacy.astroFlavoredMarkdown option completely. Importing and using components in .md files will no longer work.

What should I do?

Remove this legacy flag. It is no longer available in Astro.

astro.config.mjs

export default defineConfig({
  legacy: {
    astroFlavoredMarkdown: true,
  },
})

If you were using this feature in v1.x, we recommend using the MDX integration which allows you to combine components and JSX expressions with Markdown syntax.

Removed: Astro.resolve()

In v0.24, Astro deprecated Astro.resolve() for getting resolved URLs to assets that you might want to reference in the browser.

Astro v2.0 removes this option entirely. Astro.resolve() in your code will cause an error.

What should I do?

Resolve asset paths using import instead. For example:

src/pages/index.astro

---
import 'style.css';
import imageUrl from './image.png';
---

<img src={imageUrl} />

Removed: Astro.fetchContent()

In v0.26, Astro deprecated Astro.fetchContent() for fetching data from your local Markdown files.

Astro v2.0 removes this option entirely. Astro.fetchContent() in your code will cause an error.

What should I do?

Use Astro.glob() to fetch Markdown files, or convert to the Content Collections feature.

src/pages/index.astro

---
const allPosts = await Astro.glob('./posts/*.md');
---

Removed: Astro.canonicalURL

In v1.0, Astro deprecated Astro.canonicalURL for constructing a canonical URL.

Astro v2.0 removes this option entirely. Astro.canonicalURL in your code will cause an error.

What should I do?

Use Astro.url to construct a canonical URL.

src/pages/index.astro

---
const canonicalURL = new URL(Astro.url.pathname, Astro.site);
---

Updated: Vite 4

Astro v2.0 upgrades from Vite 3 to Vite 4, released in December 2022.

What should I do?

There should be no changes to your code necessary! We’ve handled most of the upgrade for you inside of Astro; however, some subtle Vite behaviors may still change between versions.

Refer to the official Vite Migration Guide if you run into trouble.

Astro v2.0 Experimental Flags Removed

Remove the following experimental flags from astro.config.mjs:

astro.config.mjs

import { defineConfig } from 'astro/config';

export default defineConfig({
  experimental: {
    contentCollections: true,
    prerender: true,
    errorOverlay: true,
  },
})

These features are now available by default:

• Content collections as a way to manage your Markdown and MDX files with type-safety.
• Prerendering individual pages to static HTML when using SSR to improve speed and cacheability.
• A redesigned error message overlay.

Known Issues

There are currently no known issues.