Gulp organization with Gulp 4.0, Babel, and require-dir

default.js

'use strict';

import gulp from 'gulp';
import config from '../config';
import browserSync from 'browser-sync';

gulp.task('default', gulp.parallel('html', 'scripts', 'styles', 'server', () => {
  gulp.watch(config.paths.html.all, gulp.parallel('html', gulp.series('html', browserSync.reload)));
  gulp.watch(config.paths.scripts.all, gulp.parallel('scripts', browserSync.reload));
  gulp.watch(config.paths.styles.all, gulp.parallel('styles', browserSync.reload));
}));

gulpfile.babel.js

'use strict';

import requireDir from 'require-dir';

requireDir('./gulp/tasks', { recurse: true });

html.js

'use strict';

import gulp from 'gulp';
import config from '../config';
import cp from 'child_process';

gulp.task('html', (callback) => {
  var jekyll = cp.spawn('jekyll', ['build', '-q', '--config', '_config.yml'], { stdio: 'inherit' });

  jekyll.on('exit', function (code) {
    callback(code === 0 ? null : 'ERROR: Jekyll process exited with code: ' + code);
  });
});

scripts.js

'use strict';

import gulp from 'gulp';
import config from '../config';
import coffee from 'gulp-coffee';
import sourcemaps from 'gulp-sourcemaps';

gulp.task('scripts', () => {
  return gulp.src(config.paths.scripts.entry)
    .pipe(sourcemaps.init())
    .pipe(coffee().on('error', (err) => {
      console.log('CoffeeScript Error:', err);
      this.emit('end');
    }))
    .pipe(sourcemaps.write())
    .pipe(gulp.dest(config.paths.scripts.dest));
});

server.js

'use strict';

import gulp from 'gulp';
import config from '../config';
import browserSync from 'browser-sync';

gulp.task('server', () => {
  browserSync({
    server: {
      baseDir: ['./dist']
    }
  });
});

styles.js

'use strict';

import gulp from 'gulp';
import config from '../config';
import sass from 'gulp-sass';
import sourcemaps from 'gulp-sourcemaps';
import autoprefixer from 'gulp-autoprefixer';

gulp.task('styles', () => {
  return gulp.src(config.paths.styles.entry)
    .pipe(sourcemaps.init())
    .pipe(sass().on('error', sass.logError))
    .pipe(autoprefixer({
      browsers: ['last 2 versions']
    }))
    .pipe(sourcemaps.write())
    .pipe(gulp.dest(config.paths.styles.dest));
});