Vite 8 Beta: The Rolldown-powered Vite

This post was originally published on the Vite blog

TL;DR: The first beta of Vite 8, powered by Rolldown, is now available. Vite 8 ships significantly faster production builds and unlocks future improvement possibilities. You can try the new release by upgrading vite to version 8.0.0-beta.0 and reading the migration guide.

We’re excited to release the first beta of Vite 8. This release marks a major milestone towards our goal of a unified JavaScript toolchain. Vite now uses Rolldown as its bundler, replacing the previous combination of esbuild and Rollup.

A new bundler for the web ​

Vite previously relied on two bundlers to meet differing requirements for development and production builds:

1. esbuild for fast compilation during development
2. Rollup for bundling, chunking, and optimizing production builds

This approach lets Vite focus on developer experience and orchestration instead of reinventing parsing and bundling. However, maintaining two separate bundling pipelines introduced inconsistencies: separate transformation pipelines, different plugin systems, and a growing amount of glue code to keep bundling behavior aligned between development and production.

To solve this, we built Rolldown, our next-generation bundler designed for:

• Performance: Rolldown is written in Rust and operates at native speed. It matches esbuild’s performance level and is 10–30× faster than Rollup.
• Compatibility: Rolldown supports the same plugin API as Rollup and Vite. Most Vite plugins work out of the box with Vite 8.
• More Features: Rolldown unlocks more advanced features for Vite, including full bundle mode, more flexible chunk split control, module-level persistent cache, Module Federation, and more.

Unifying the toolchain ​

The impact of Vite’s bundler swap goes beyond performance. Bundlers leverage parsers, resolvers, transformers, and minifiers. Rolldown uses Oxc, another project led by VoidZero, for these purposes.

That makes Vite the entry point to an end-to-end toolchain maintained by the same team: The build tool (Vite), the bundler (Rolldown), and the compiler (Oxc).

This alignment ensures behavior consistency across the stack and allows us to rapidly adopt and align with new language specifications as JavaScript continues to evolve. It also unlocks a wide range of improvements that previously couldn’t be done by Vite alone. For example, we can leverage Oxc’s semantic analysis to perform better tree-shaking in Rolldown.

How Vite migrated to Rolldown ​

The migration to a Rolldown-powered Vite is a foundational change. Therefore, our team took deliberate steps to implement it without sacrificing stability or ecosystem compatibility.

First, a separate rolldown-vite package was released as a technical preview. This allowed us to work with early adopters without affecting the stable version of Vite. Early adopters benefited from Rolldown’s performance gains while providing valuable feedback. Highlights:

• Linear’s production build times were reduced from 46s to 6s
• Mercedes-Benz.io cut their build time down by up to 38%
• Beehiiv reduced their build time by 64%

Next, we set up a test suite for validating key Vite plugins against rolldown-vite. This CI job helped us catch regressions and compatibility issues early, especially for frameworks and meta-frameworks such as SvelteKit, react-router and Storybook.

Lastly, we built a compatibility layer to help migrate developers from Rollup and esbuild options to the corresponding Rolldown options.

As a result, there is a smooth migration path to Vite 8 for everyone.

Migrating to Vite 8 Beta ​

Since Vite 8 touches the core build behavior, we focused on keeping the configuration API and plugin hooks unchanged. We created a migration guide to help you upgrade.

There are two available upgrade paths:

1. Direct Upgrade: Update vite in package.json and run the usual dev and build commands.
2. Gradual Migration: Migrate from Vite 7 to the rolldown-vite package, and then to Vite 8. This allows you to identify incompatibilities or issues isolated to Rolldown without other changes to Vite. (Recommended for larger or complex projects)

If you use a framework or tool that uses Vite as dependency, for example Astro, Nuxt, or Vitest, you have to override the vite dependency in your package.json, which works slightly different depending on your package manager:

{
  "overrides": {
    "vite": "8.0.0-beta.0"
  }
}

{
  "resolutions": {
    "vite": "8.0.0-beta.0"
  }
}

{
  "pnpm": {
    "overrides": {
      "vite": "8.0.0-beta.0"
    }
  }
}

{
  "overrides": {
    "vite": "8.0.0-beta.0"
  }
}

After adding these overrides, reinstall your dependencies and start your development server or build your project as usual.

Additional Features in Vite 8 ​

In addition to shipping with Rolldown, Vite 8 comes with:

• Built-in tsconfig paths support: Developers can enable it by setting resolve.tsconfigPaths to true. This feature has a small performance cost and is not enabled by default.
• emitDecoratorMetadata support: Vite 8 now has built-in automatic support for TypeScript’s emitDecoratorMetadata option.

Looking Ahead ​

Speed has always been a defining feature for Vite. The integration with Rolldown and, by extension, Oxc means JavaScript developers benefit from Rust’s speed. Upgrading to Vite 8 should result in performance gains simply from using Rust.

We are also excited to ship Vite’s Full Bundle Mode soon, which drastically improves Vite’s dev server speed for large projects. Preliminary results show 3× faster dev server startup, 40% faster full reloads, and 10× fewer network requests.

Another defining Vite feature is the plugin ecosystem. We want JavaScript developers to continue extending and customizing Vite in JavaScript, the language they’re familiar with, while benefiting from Rust’s performance gains. Our team is working to accelerate JavaScript plugin usage in these Rust-based systems.

Upcoming optimizations that are currently experimental:

• Raw AST transfer. Allow JavaScript plugins to access the Rust-produced AST with minimal overhead.
• Native MagicString transforms. Simple custom transforms with logic in JavaScript but computation in Rust.

Connect with us ​

If you’ve tried Vite 8 beta, then we’d love to hear your feedback! Please report any issues or share your experience:

• Discord: Join our community server for real-time discussions
• GitHub: Share feedback on GitHub discussions
• Issues: Report issues on the rolldown-vite repository for bugs and regressions
• Wins: Share your improved build times in the rolldown-vite-perf-wins repository

We appreciate all reports and reproduction cases. They help guide us towards the release of a stable 8.0.0.