SortableJS is a mature, standalone JavaScript library for creating reorderable drag-and-drop lists and grids. It supports mouse, touch, and pointer events across modern browsers and legacy browsers like IE11 and Edge. The library is designed as a modular system with a core (Sortable class) and optional plugins (AutoScroll, Swap, MultiDrag, OnSpill) that can be mounted selectively. It exports UMD and ESM builds, integrates with major frameworks (React, Vue, Angular) via separate adapter packages, and provides a rich API with options for grouping, animation, handles, filtering, and custom events. The codebase demonstrates a well-thought-out plugin architecture, event dispatching, and animation state management, though some build tooling and browser workarounds show its age.