parcel-optimizer-custom-terser

Install

yarn add parcel-optimizer-custom-terser -D

or 

npm install parcel-optimizer-custom-terser --save-dev

default minify options

const minifyOptions: MinifyOptions = {
      compress: false,
      ecma: 2020,
      ie8: false,
      keep_classnames: undefined,
      keep_fnames: false,
      module: true,
      safari10: false,
      sourceMap: {
        includeSources: true,
        filename: bundle.name,
        url: bundle.name + '.map',
      },
      toplevel: true,
    };

.parcelrc example

{
    "extends": ["@parcel/config-default"],
    "optimizers": {
        "*.js": [
            "parcel-optimizer-custom-terser"
        ]
    }
}