Drupal Commerce technologies are those of Drupal 7, orchestrated the Drupal way. This makes for a very flexible and tightly maintained stack that is perfect for both small- and large-scale eCommerce projects.
Drupal is written in PHP, without classes, and borrows multiple concepts from various programming paradigms. Drupal has its own coding standards to ensure maintainability, compliance, and scalability; it also has dedicated security teams. Drupal is a mature, sophisticated, and well-maintained platform that is ideally suited for Drupal Commerce.