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Bunchee

Bunchee is a zero configuration bundler makes bundling JS/TS library effortless. It’s built on top of Rollup and SWC, allowing you to focus on writing code and generating multiple bundles (CommonJS or ESModule) at the same time.

It uses the standard exports configuration in package.json as the only source of truth, and uses entry file conventions


to match your exports and build them into bundles.

Quick start

1. 
   
   
   
   You can use Bunchee to configure the package.json automatically using the below command:
   
   
   
   
   
   
   

   CODE Kopieren

   # Use bunchee to prepare package.json configuration
   
   npm exec bunchee - prepare
   
   

   
   
   
   
   
   
   
   

   Or you can configure the package.json manually. The below configuration is an example picked from documentation.
   
   

   
   
   
   
   

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   {
   
    "files": ["dist"],
   
    "exports": {
   
    "import": {
   
    "types": "./dist/es/index.d.mts",
   
    "default": "./dist/es/index.mjs"
   
    },
   
    "require": {
   
    "types": "./dist/cjs/index.d.ts",
   
    "default": "./dist/cjs/index.js"
   
    }
   
    },
   
    "scripts": {
   
    "build": "bunchee"
   
    }
   
   }
   
   

   
   
   
   
   
   
   
   

   3. Build

   
   
   

   In the configuration step above, we have defined the build script. You just have to execute this script — npm run build, index.ts become the entry point for the bundler and generates the output based on the exports object.

   
   
   

   For example: src/index.ts will match the exports name “.” or the only main export.

   
   
   

   
   
   
   Exports in core/package.json
   

   
   
   

   This below code is picked from
   
   

   
   
   
   
   

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   "exports": {
   
    "./package.json": "./package.json",
   
    ".": {
   
    "types": "./dist/index.d.ts",
   
    "default": "./dist/index.js"
   
    },
   
    "./presets": {
   
    "types": "./dist/presets.d.ts",
   
    "default": "./dist/presets.js"
   
    }
   
   },
   
   

   
   
   
   
   
   
   
   

   
   
   
   Exports in nuxt/package.json
   

   
   
   

   This below code is picked from , we study large open source projects and . We offer with us to discuss your project.

   
   
   



2. https://github.com/t3-oss/t3-env/blob/main/packages/core/package.json#L40