A simple guide to setup Atomizer with SvelteKit.

Create a new project

If you do not have a project setup already, you can create a new one using SvelteKit’s Getting Started page.

npm create svelte@latest my-app
cd my-app
npm install

Install the PostCSS plugin

For a SvelteKit project, the postcss-atomizer library makes it easy to setup Atomizer.

npm i postcss-atomizer -D

Enable PostCSS

Update your svelte.config.js file, to import vitePreprocess to enable processing <style> blocks as PostCSS.

import { vitePreprocess } from '@sveltejs/kit/vite';

const config = {
    // ...
    preprocess: vitePreprocess(),

Create your Atomizer config

Create the ./atomizer.config.cjs config file so that Atomizer can parse your SvelteKit files.

module.exports = {
    content: [

Create the PostCSS config

Create the ./postcss.config.cjs file to configure the Atomizer plugin.

const atomizer = require('postcss-atomizer');

module.exports = {
    plugins: [
            config: './atomizer.config.cjs',

Add the CSS file

Create an a stub ./src/app.css file with a generic comment (Svelte will not build properly if its empty).

/** todo */

Import the CSS

Add a new file ./src/routes/+layout.svelte which includes the CSS file:

    import "../app.css";

<slot />

Start your build process

Run your build setup as configured in your project’s package.json.

npm run dev

Begin using Atomizer

Start adding Atomizer classes to the ./src/routes/+page.svelte file.

<h1 class="Fw(b) Fz(2rem)">Welcome!</h1>