rollup.config.ts

import resolve from '@rollup/plugin-node-resolve';
import commonjs from '@rollup/plugin-commonjs';
import typescript from 'rollup-plugin-typescript2';

import pkg from './package.json';

const deps = Object.keys(pkg.dependencies);

export default {
  input: 'src/index.ts',
  output: [
    { file: pkg.main, format: 'cjs', sourcemap: true },
    { file: pkg.module, format: 'esm', sourcemap: true },
  ],
  // Indicate here external modules you don't wanna include in your bundle (i.e.: 'lodash')
  external: [...deps],
  watch: {
    include: 'src/**',
  },
  plugins: [
    // Compile TypeScript files
    typescript({ useTsconfigDeclarationDir: true }),
    // Allow bundling cjs modules (unlike webpack, rollup doesn't understand cjs)
    commonjs(),
    // Allow node_modules resolution, so you can use 'external' to control
    // which external modules to include in the bundle
    // https://github.com/rollup/rollup-plugin-node-resolve#usage
    resolve(),
  ],
}