A simple guide to setup Grunt with PostCSS.

Install the package

Install grunt-atomizer to configure and execute Atomizer.

npm i grunt-atomizer grunt-contrib-watch -D

Update the config

Then configure your Gruntfile.js with the following tasks.

// load the task

// use grunt-contrib-watch to watch for changes and run tasks
watch: {
    dev: {
        options: {
            livereload: true
        files: [
        tasks: ['atomizer']
atomizer: {
    options: {
        // set a context to increase specificity
        namespace: '#atomic',
        // pass a base config file
        configFile: './config/manual-config.js',
        // augment classNames in the base config file
        config: {
            classNames: ['D(b)']
        // the final config file used by the tool will be written
        // in the following file:
        configOutput: 'tmp/config.json',
    files: [
            // parse your project's html files to automatically add
            // found ACSS classes to your config
            src: ['./src/*.html'],
            // generate the css in the file below
            dest: './dist/atomizer.css'

grunt.registerTask('dev', ['watch:dev']);

Start your build process

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

npm run dev

Begin using Atomizer

Add the generated PostCSS CSS to your template, then start adding Atomizer classes to your markup.

<!DOCTYPE html>
<html lang="en">
        <meta charset="utf-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <link rel="stylesheet" href="/dist/atomizer.css" />
        <h1 class="Fw(b) Fz(2rem)">Welcome!</h1>