Developer Reference 

The preceding sections describe Grid Elements from an editor's or an integrator's point of view: how a grid structure is defined (Grid Definitions), how its data is stored (Data Model), how editors work with it (Editor Guide), and how it reaches frontend output (Rendering). This section is for a different audience: developers extending Grid Elements itself, writing another extension that needs to cooperate with it, or maintaining a project that XCLASSes or overrides part of TYPO3's backend and needs to know where Grid Elements already touches that same code.

Grid Elements is implemented almost entirely through TYPO3 Core's PSR-14 events and a small number of legacy $GLOBALS hooks that Core has not replaced with events for the relevant operations yet. XCLASSing is exceptional and limited to a single, explicitly opt-in case. Extension Points catalogs all of these by their actual current class and event names, and states plainly where an older hook has been superseded rather than presenting it as current.