rollup.config.js

import typescript from 'rollup-plugin-typescript2';

import { tmpdir } from 'os';
import { builtinModules } from 'module';
import { join as pathJoin } from 'path';

import pkg from './package.json';

const cacheRoot = pathJoin(tmpdir(), '.rpt2_cache');

const CORE_MODULE_RE = /(^_|\/)/;
const coreModules = builtinModules.filter(name => (
    !CORE_MODULE_RE.test(name)
));

const src = pathJoin(__dirname, 'src');
const lib = pathJoin(__dirname, 'lib');

export default {
    input: pathJoin(src, 'index.ts'),
    plugins: [
        typescript({
            cacheRoot,

            declarationDir: lib,

            tsconfigOverride: {
                outDir: lib,
                rootDir: src,
                include: [src]
            }
        })
    ],
    external: [
        ...Object.keys(pkg.dependencies || {}),
        ...Object.keys(pkg.peerDependencies || {}),
        ...coreModules
    ],
    output: [
        {
            file: pathJoin(lib, 'index.js'),
            format: 'cjs',
            exports: 'named'
        },
        {
            file: pathJoin(lib, 'index.mjs'),
            format: 'esm'
        }
    ]
};