# Enum.RuntimeUndoBehavior

Roblox Engine API enum from Roblox Studio 0.744.0.7441077 (version-7aaa6838d36c4448).

- HTML page: https://rapi.sleaze.dev/enums/RuntimeUndoBehavior/
- Roblox documentation: https://create.roblox.com/docs/reference/engine/enums/RuntimeUndoBehavior

Controls how [`ChangeHistoryService`](https://rapi.sleaze.dev/classes/ChangeHistoryService.md) records and handles undo history during a Studio playtest session.

## Items

| Name | Value | Description |
| --- | --- | --- |
| `Aggregate` | 0 | Rejects waypoint requests during a run session; all runtime changes accumulate into a single waypoint that is reverted together when the session stops or resets. |
| `Snapshot` | 1 | Accepts waypoint requests during a run session and captures a snapshot of each instance's position and velocity at every waypoint boundary so that physics state can be fully restored on undo. |
| `Hybrid` | 2 | Accepts waypoint requests during a run session but excludes unsolicited physics changes (position and velocity drift from simulation) from the recorded history. |

## Used by

Each entry lists the class, then the role and names of the members that use this type.

- [Studio](https://rapi.sleaze.dev/classes/Studio.md): property `RuntimeUndoBehavior`