storybook/lib/core/server.js

const assign = require('@babel/runtime/core-js/object/assign');
const defaultWebpackConfig = require('./dist/server/config/defaults/webpack.config');
const serverUtils = require('./dist/server/utils');
const buildStatic = require('./dist/server/build-static');
const buildDev = require('./dist/server/build-dev');

module.exports = assign({}, defaultWebpackConfig, buildStatic, buildDev, serverUtils, {
  indexHtmlPath: require.resolve('./src/server/index.html.ejs'),
  iframeHtmlPath: require.resolve('./src/server/iframe.html.ejs'),
});