| --- |
| title: SWC Failed to Load |
| --- |
|
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| ## Why This Message Occurred |
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| Next.js now uses Rust-based compiler [SWC](https://swc.rs/) to compile JavaScript/TypeScript. This new compiler is up to 17x faster than Babel when compiling individual files and up to 5x faster Fast Refresh. |
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| SWC requires a binary to be downloaded that is compatible with your system. In some cases this binary may fail to load either from failing to download or an incompatibility with your architecture. |
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| ## Possible Ways to Fix It |
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| When on an M1 Mac and switching from a Node.js version without M1 support to one with, e.g. v14 to v16, you may need a different swc dependency which can require re-installing `node_modules` (`npm i --force` or `yarn install --force`). |
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| On Windows make sure you have Microsoft Visual C++ Redistributable installed. https://docs.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist |
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| Alternatively, you might need to allow optional packages to be installed by your package manager (remove `--no-optional` flag) for the package to download correctly. |
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| In some cases your package manager (e.g. `npm`) might have generated a lockfile that only includes `optionalDependencies` specific to the platform it was generated on, preventing the `optionalDependency` needed for CI from being installed. |
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| This can be fixed by removing the lockfile and regenerating it with a newer version of your package manager `npm i -g npm@latest`. |
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| If SWC continues to fail to load you can opt-out by disabling `swcMinify` in your `next.config.js` or by adding a `.babelrc` to your project with the following content: |
|
|
| ```json filename=".babelrc" |
| { |
| "presets": ["next/babel"] |
| } |
| ``` |
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| Be sure to report the issue on [the feedback thread](https://github.com/vercel/next.js/discussions/30468) so that we can investigate it further. |
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| ## Useful Links |
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| - [SWC Feedback Thread](https://github.com/vercel/next.js/discussions/30468) |
| - [SWC Disabled Document](/docs/messages/swc-disabled) |
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|
