js-broadcast-channel/tsup.config.ts

Broadcast-js

import { defineConfig } from 'tsup'

export default defineConfig({
  entry: ['src/index.ts'],
  format: ['esm'],
  dts: true,
  minify: true,
  treeshake: true,
  target: 'es2020',
  clean: true,
  esbuildOptions: (options, { format }) => {
    if (format === 'esm') {
      options.mangleProps = /^_/
    }
  }
})