Drupal coding Knowing and following Drupal coding standards In particular, knowing how to use doxygen commenting according to Drupal standards Using and partly understanding the Drupal hook system Using and partly understanding the Drupal hook_alter system Being able to create new modules from scratch Basic familiarity with the form and render system (including knowledge about some of the form/render elements, and the hook_form_alter and hook_form_FORM_ID_alter functions) Knowing how to look up API documentation for Drupal core, and the most-used modules Being able to interpret well-documented Drupal code examples (at a reasonably complex level)