I an Acquia Certified Drupal Developer. I have designed and built a number of large systems, integrating with a dozen 3rd party systems (such as SalesForce, various payment gateways, etc). I have built various custom modules, custom themes and even swapped out the default Drupal render engine using TWIG for increased performance and flexibility. If you are looking for someone to design and built your next Drupal project - look no further.