Migration from v4 ​

Node.js Support ​

Vite no longer supports Node.js 14 / 16 / 17 / 19, which reached its EOL. Node.js 18 / 20+ is now required.

Rollup 4 ​

Vite is now using Rollup 4 which also brings along its breaking changes, in particular:

• Import assertions (assertions prop) has been renamed to import attributes (attributes prop).
• Acorn plugins are no longer supported.
• For Vite plugins, this.resolve skipSelf option is now true by default.
• For Vite plugins, this.parse now only supports the allowReturnOutsideFunction option for now.

Read the full breaking changes in Rollup's release notes for build-related changes in build.rollupOptions.

Deprecate CJS Node API ​

The CJS Node API of Vite is deprecated. When calling require('vite'), a deprecation warning is now logged. You should update your files or frameworks to import the ESM build of Vite instead.

In a basic Vite project, make sure:

1. The vite.config.js file content is using the ESM syntax.
2. The closest package.json file has "type": "module", or use the .mjs extension, e.g. vite.config.mjs.

For other projects, there are a few general approaches:

• Configure ESM as default, opt-in to CJS if needed: Add "type": "module" in the project package.json. All *.js files are now interpreted as ESM and needs to use the ESM syntax. You can rename a file with the .cjs extension to keep using CJS instead.
• Keep CJS as default, opt-in to ESM if needed: If the project package.json does not have "type": "module", all *.js files are interpreted as CJS. You can rename a file with the .mjs extension to use ESM instead.
• Dynamically import Vite: If you need to keep using CJS, you can dynamically import Vite using import('vite') instead. This requires your code to be written in an async context, but should still be manageable as Vite's API is mostly asynchronous.

See the troubleshooting guide for more information.

General Changes ​

SSR externalized modules value now matches production ​

In Vite 4, SSR externalized modules are wrapped with .default and .__esModule handling for better interoperability, but it doesn't match the production behaviour when loaded by the runtime environment (e.g. Node.js), causing hard-to-catch inconsistencies. By default, all direct project dependencies are SSR externalized.

Vite 5 now removes the .default and .__esModule handling to match the production behaviour. In practice, this shouldn't affect properly-packaged dependencies, but if you encounter new issues loading modules, you can try these refactors:

// Before:
import { foo } from 'bar'

// After:
import _bar from 'bar'
const { foo } = _bar

// Before:
import { foo } from 'bar'

// After:
import _bar from 'bar'
const { foo } = _bar

// Before:
import foo from 'bar'

// After:
import * as _foo from 'bar'
const foo = _foo.default

// Before:
import foo from 'bar'

// After:
import * as _foo from 'bar'
const foo = _foo.default

Note that these changes matches the Node.js behaviour, so you can also run the imports in Node.js to test it out. If you prefer to stick with the previous behaviour, you can set legacy.proxySsrExternalModules to true.

worker.plugins is now a function ​

In Vite 4, worker.plugins accepted an array of plugins ((Plugin | Plugin[])[]). From Vite 5, it needs to be configured as a function that returns an array of plugins (() => (Plugin | Plugin[])[]). This change is required so parallel worker builds run more consistently and predictably.

Allow path containing . to fallback to index.html ​

In Vite 4, accessing a path containing . did not fallback to index.html even if appType is set to 'SPA' (default). From Vite 5, it will fallback to index.html.

Note that the browser will no longer show the 404 error message in the console if you point the image path to a non-existent file (e.g. <img src="./file-does-not-exist.png">).

Manifest files are now generated in .vite directory by default ​

In Vite 4, the manifest files (build.manifest, build.ssrManifest) was generated in the root of build.outDir by default. From Vite 5, those will be generated in the .vite directory in the build.outDir by default.

CLI shortcuts require an additional Enter press ​

CLI shortcuts, like r to restart the dev server, now require an additional Enter press to trigger the shortcut. For example, r + Enter to restart the dev server.

This change prevents Vite from swallowing and controlling OS-specific shortcuts, allowing better compatibility when combining the Vite dev server with other processes, and avoids the previous caveats.

Remove --https flag and https: true ​

--https flag sets https: true. This config was meant to be used together with the automatic https certification generation feature which was dropped in Vite 3. This config no longer makes sense as it will make Vite start a HTTPS server without a certificate. Both @vitejs/plugin-basic-ssl and vite-plugin-mkcert sets https setting regardless of the https value, so you can just remove --https and https: true.

Remove resolvePackageEntry and resolvePackageData APIs ​

The resolvePackageEntry and resolvePackageData APIs are removed as they exposed Vite's internals and blocked potential Vite 4.3 optimizations in the past. These APIs can be replaced with third-party packages, for example:

• resolvePackageEntry: import.meta.resolve or the import-meta-resolve package.
• resolvePackageData: Same as above, and crawl up the package directory to get the root package.json. Or use the community vitefu package.

import { resolve } from 'import-meta-env'
import { findDepPkgJsonPath } from 'vitefu'
import fs from 'node:fs'

const pkg = 'my-lib'
const basedir = process.cwd()

// `resolvePackageEntry`:
const packageEntry = resolve(pkg, basedir)

// `resolvePackageData`:
const packageJsonPath = findDepPkgJsonPath(pkg, basedir)
const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf-8'))

import { resolve } from 'import-meta-env'
import { findDepPkgJsonPath } from 'vitefu'
import fs from 'node:fs'

const pkg = 'my-lib'
const basedir = process.cwd()

// `resolvePackageEntry`:
const packageEntry = resolve(pkg, basedir)

// `resolvePackageData`:
const packageJsonPath = findDepPkgJsonPath(pkg, basedir)
const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf-8'))

Removed Deprecated APIs ​

• Default exports of CSS files (e.g import style from './foo.css'): Use the ?inline query instead
• import.meta.globEager: Use import.meta.glob('*', { eager: true }) instead
• ssr.format: 'cjs' and legacy.buildSsrCjsExternalHeuristics (#13816)

Advanced ​

There are some changes which only affect plugin/tool creators.

• [#14119] refactor!: merge PreviewServerForHook into PreviewServer type

Also there are other breaking changes which only affect few users.

• [#14098] fix!: avoid rewriting this (reverts #5312)
  • Top level this was rewritten to globalThis by default when building. This behavior is now removed.
• [#14231] feat!: add extension to internal virtual modules
  • Internal virtual modules' id now has an extension (.js).
• [#14583] refactor!: remove exporting internal APIs
  • Removed accidentally exported internal APIs: isDepsOptimizerEnabled and getDepOptimizationConfig
  • Removed exported internal types: DepOptimizationResult, DepOptimizationProcessing, and DepsOptimizer
  • Renamed ResolveWorkerOptions type to ResolvedWorkerOptions
• [#5657] fix: return 404 for resources requests outside the base path
  • In the past, Vite responded to requests outside the base path without Accept: text/html, as if they were requested with the base path. Vite no longer does that and responds with 404 instead.

Migration from v3 ​

Check the Migration from v3 Guide in the Vite v4 docs first to see the needed changes to port your app to Vite v4, and then proceed with the changes on this page.