@vitejs/plugin-react-swc 
Speed up your Vite dev server with SWC
Installation
npm i -D @vitejs/plugin-react-swc
Usage
import { defineConfig } from "vite";
import react from "@vitejs/plugin-react-swc";
export default defineConfig({
plugins: [react()],
});
Caveats
This plugin has limited options to enable good performances and be transpiler agnostic. Here is the list of non-configurable options that impact runtime behaviour:
- useDefineForClassFields is always activated, as this matches the current ECMAScript spec
jsx runtime
is always automatic
- In development:
- esbuild is disabled, so the esbuild configuration has no effect
target
is ignored and defaults to es2020
(see devTarget
)- JS files are not transformed
- tsconfig is not resolved, so properties other than the ones listed above behaves like TS defaults
Options
jsxImportSource
Control where the JSX factory is imported from.
@default
"react"
react({ jsxImportSource: "@emotion/react" });
tsDecorators
Enable TypeScript decorators. Requires experimentalDecorators
in tsconfig.
@default
false
react({ tsDecorators: true });
plugins
Use SWC plugins. Enable SWC at build time.
react({ plugins: [["@swc/plugin-styled-components", {}]] });
devTarget
Set the target for SWC in dev. This can avoid to down-transpile private class method for example.
For production target, see https://vitejs.dev/config/build-options.html#build-target.
@default
"es2020"
react({ devTarget: "es2022" });
parserConfig
Override the default include list (.ts, .tsx, .mts, .jsx, .mdx).
This requires to redefine the config for any file you want to be included (ts, mdx, ...).
If you want to trigger fast refresh on compiled JS, use jsx: true
. Exclusion of node_modules should be handled by the function if needed. Using this option to use JSX inside .js
files is highly discouraged and can be removed in any future version.
react({
parserConfig(id) {
if (id.endsWith(".res")) return { syntax: "ecmascript", jsx: true };
if (id.endsWith(".ts")) return { syntax: "typescript", tsx: false };
},
});
useAtYourOwnRisk_mutateSwcOptions
The future of Vite is with OXC, and from the beginning this was a design choice to not exposed too many specialties from SWC so that Vite React users can move to another transformer later.
Also debugging why some specific version of decorators with some other unstable/legacy feature doesn't work is not fun, so we won't provide support for it, hence the name useAtYourOwnRisk
.
react({
useAtYourOwnRisk_mutateSwcOptions(options) {
options.jsc.parser.decorators = true;
options.jsc.transform.decoratorVersion = "2022-03";
},
});
Consistent components exports
For React refresh to work correctly, your file should only export React components. The best explanation I've read is the one from the Gatsby docs.
If an incompatible change in exports is found, the module will be invalidated and HMR will propagate. To make it easier to export simple constants alongside your component, the module is only invalidated when their value changes.
You can catch mistakes and get more detailed warning with this eslint rule.