What is jMonkeyEngine? jMonkeyEngine is a game engine made for developers who want to create 3D games following modern technology standards. The framework is programmed entirely in Java aimed at wide accessibility and quick deployment to desktop, web, and mobile platforms. Who is jMonkeyEngine for? jMonkeyEngine is not a visual “RPG Maker” or a drag-and-drop “FPS mod”. If you are comfortable writing Java code, you can rely on jMonkeyEngine as your next 3D game’s foundation. jMonkeyEngine is a state-of-the-art starting point for any aspiring 3D games developer.