Instantiating Harmony instance - BepInEx/HarmonyX GitHub Wiki

Patching always starts by initializing a Harmony instance -- a named instance that exposes patching and unpatching functionality of Harmony. Each instance has a unique ID to identify it, allow unpatching and enable patch ordering via HarmonyBefore and HarmonyAfter attributes.

Creating a Harmony instance is simple:

var harmony = new Harmony("com.company.project.product");

The ID is encouraged to use reverse domain name notation, but it is not enforced. However ID of a Harmony instance must be unique!