This is third iteration of GunshotWound mod for GTA V. GunShot Wound is bringing most realistic damage system to GTAV. GSW3 is based on Entity-Component-System architecture(using Leopotam ECS Framework) and RagePluginHook for interacting with GTAV. If you want to contribute, you need to learn more about ECS.
Main feature of GSW3 is fully configurable content. You can add or modify mod content(wounds, effects, bodyparts, etc) any way you want. You can find more info about that in .xml-configs in folder GSW3\GswData.