Single Directory Components Bring Structure to Drupal Theming Workflows

Traditional Drupal theming workflows often separate templates, styles, and scripts across multiple locations, making it difficult to trace how interface elements are built. In a blog post, frontend developer and team lead Volha Tsiamliak outlines how Single Directory Components (SDC) address this fragmentation by introducing a component-based structure within Drupal.

SDC groups all parts of a user interface element—Twig template, CSS, JavaScript, and configuration—into a single directory. This removes the need for template discovery through debug tools and reduces reliance on scattered asset management. The result is a more predictable structure where developers can locate, understand, and modify components without navigating multiple layers of the theme system.

The approach also defines component data explicitly through YAML metadata, including props and slots. This allows frontend developers to build and test components independently of backend logic and integrate them with tools such as Storybook. The model improves collaboration by enabling teams to validate component behaviour earlier in the development process.

The post frames SDC as a structural shift rather than a feature addition. By consolidating assets and standardising component definition, Drupal’s theming layer moves closer to modern frontend practices based on modular design and reuse. While the analysis focuses on architectural benefits rather than measurable performance outcomes, it positions SDC as a foundation for more maintainable and scalable frontend workflows.