webpack.mix.js

// Helpers
const recursiveCompiling = (path, outputPath, funcName, appendedPath = '') => {
  const dirPath = `${path}${appendedPath}`;
  const filenames = fs.readdirSync(dirPath);

  filenames
    .filter(filename => !(filename.charAt(0) === '_'))
    .filter(filename => !(filename.charAt(0) === '.'))
    .forEach(filename => {
      const filePath = `${path}${appendedPath}/${filename}`; 
      const isFile = fs.lstatSync(filePath).isFile();
      
      if (isFile) {
        const compilingPath = `${path}${appendedPath}/${filename}`;
        const compilingOutputPath = `${outputPath}${appendedPath}`;

        mix[funcName](compilingPath, compilingOutputPath);
      } else {
        const newAppendedPath = `${appendedPath}/${filename}`;
        recursiveCompiling(path, outputPath, funcName, newAppendedPath);
      }
    });
}

// Compiling Sass
const sassPath = 'resources/assets/sass';
const sassOuputPath = 'public/css';
recursiveCompiling(sassPath, sassOuputPath, 'sass');

// Compiling Javascript
const jsPath = 'resources/assets/js';
const jsOuputPath = 'public/js';
recursiveCompiling(jsPath, jsOuputPath, 'js');

// Versioning
mix.version();