StarterKit.php

<?php

namespace Drupal\starterkit_theme;

use Drupal\Core\Theme\StarterKitInterface;
final class StarterKit implements StarterKitInterface {
    
    /**
     * {@inheritdoc}
     */
    public static function postProcess(string $working_dir, string $machine_name, string $theme_name) : void {
        $readme_file = "{$working_dir}/README.md";
        try {
            file_put_contents($readme_file, "{$theme_name} theme, generated from starterkit_theme. Additional information on generating themes can be found in the [Starterkit documentation](https://www.drupal.org/docs/core-modules-and-themes/core-themes/starterkit-theme).");
        } catch (\Throwable) {
        }
    }

}