carbon-components-svelte/examples/rollup/rollup.config.js

import { terser } from "rollup-plugin-terser";
import commonjs from "@rollup/plugin-commonjs";
import resolve from "@rollup/plugin-node-resolve";
import serve from "rollup-plugin-serve";
import svelte from "rollup-plugin-svelte";
import livereload from "rollup-plugin-livereload";
import sveltePreprocess from "svelte-preprocess";

const PORT = process.env.PORT || 3000;
const PROD = !process.env.ROLLUP_WATCH;

export default {
  input: "src/index.js",
  output: {
    sourcemap: !PROD,
    format: "iife",
    name: "app",
    file: "public/build/bundle.js",
  },
  plugins: [
    svelte({
      dev: !PROD,
      preprocess: sveltePreprocess(),
      css: (css) => css.write("bundle.css", !PROD),
    }),
    resolve({ browser: true, dedupe: ["svelte"] }),
    commonjs(),
    !PROD && serve({ contentBase: ["public"], port: PORT }),
    !PROD && livereload("public"),
    PROD && terser(),
  ],
};