Stackable is a Gutenberg addon that comes with ready-made designs and UI kits. It comes with 25 blocks, many of which support the use of custom fields. In addition to support for Advanced Custom Fields, Stackable also works with Toolset. The plugin works with any theme, but the Stackable and Blocksy Theme developers have collaborated to ensure that the two products work well together. The plugin comes with a Role Manager to help manage content editing capabilities. The agency lifetime package is for unlimited sites with lifetime updates and support.