Drupal developer since 2008, as a freelance I can manage your whole project or integrate your team. But what does "Drupal developer" mean, in fact ?
Site builder
As a Drupal site builder, I build a Drupal website by using Drupal Core and contrib modules at their best. a good Drupal site builder must conceive a strong and evolutive architecture, in order to allow further developments. She / he must know Drupal's roadmap and take inspiration from it in order to have a clear vision of the future. At last, a Drupal site builder must be able to code a little bit and know Drupal's hooks system, in order to tie together the functionalities of the different modules.
Drupal developer
As a Drupal developer, I develop Drupal custom modules for your website. I study how to best use Drupal Core APIs and those of the main contrib modules: Entity, Fields, Views, Forms, Rules, Migrate, Webform... Beiing able to lead those developments while capitalizing on the existing code in the Drupal ecosystem, while taking into account the evolution directions of Drupal, are the main skills of the Drupal developer.
Drupal designer
At last I'm a Drupal designer, which means I'm able to build a Drupal theme with HTML5, CSS3 and JavaScript. There is a "Drupal way" to do it which guarantees more performance, more security and a better evolutivity. A good Drupal designer must know Drupal's templating system, its Twig language and preprocessing functions, and must of course master the usual frontend technologies: less / sass, yarn / npm, laravel-mix / webpack / gulp / grunt, ...