In some embodiments, a layer-partitioned virtual world system includes at least one server computing device, a plurality of third-party software engines, and one or more client devices. The server computing device includes at least one processor and memory storing a base layer including a persistent virtual world system that includes a plurality of virtual objects, the base layer supporting a plurality of virtual world layers providing further functionality to the persistent virtual world system through a plurality of applications. The plurality of third-party software engines are hosted on corresponding third-party server computing devices communicatively coupled to the at least one server computing device via a network and providing services to the plurality of applications. The one or more client devices receive and display composited virtual frames corresponding to the base layer and further functionalities of one or more of the virtual world layers.