prettier/scripts/build/rollup.index.config.js

import baseConfig from "./rollup.base.config.js";
import resolve from "rollup-plugin-node-resolve";
import commonjs from "rollup-plugin-commonjs";
import json from "rollup-plugin-json";

export default Object.assign(baseConfig, {
  entry: "index.js",
  dest: "dist/index.js",
  format: "cjs",
  plugins: [json(), resolve({ preferBuiltins: true }), commonjs()],
  external: ["assert"]
});