This is an Ember addon that provides sortable UI primitives as modifiers (sortable-group, sortable-item, sortable-handle). It is a well-crafted, modern Ember v2 addon built with TypeScript and Glint, supporting mouse, touch, and keyboard interactions with full accessibility (ARIA live regions, keyboard reordering, focus management). The architecture is modifier-based: `sortable-group` coordinates a list of items, `sortable-item` handles drag/drop and animation, and `sortable-handle` marks the drag handle. A service manages internal state for multiple groups. It exports test helpers (`drag`, `reorder`) for acceptance testing. The codebase demonstrates strong event-driven design with proper cleanup, throttle/bind for performance, and a scroll-container utility for auto-scrolling during drag. It is not a hybrid; it is purely a front-end library (application).