build.ts

import React from 'react';
import ReactDOM from 'react-dom/server';
import fs from 'fs';
import { PurgeCSS } from 'purgecss';
import createCleanCss from 'clean-css';

import { Wrapper } from './src/Wrapper';
import { StyleMeta } from '@bdxtown/canaille';

const cleancss = new createCleanCss();

async function generate() {
    const markup = `
<!DOCTYPE html>
${ReactDOM.renderToStaticMarkup(React.createElement(Wrapper))}
    `;

    const css = StyleMeta.getServerSideStyle();

    const output = await new PurgeCSS().purge({
        content: [
          {
            raw: markup,
            extension: 'html'
          },
        ],
        css: [
          {
            raw: css
          }
        ]
    })

    fs.writeFileSync('index.html', markup);
    fs.writeFileSync('ssr.css', cleancss.minify(output[0].css).styles.replace(/@layer components/g, '@layer cmps'));
}

generate();