1. An entity modeling system, comprising: at least one processor; a data store storing a plurality of entity building blocks, the plurality of entity building blocks representing a subset of elements of the entity modeling system; at least one non-transitory computer readable medium; and stored instructions embodied on the at least one non-transitory computer readable medium and translatable by the at least one processor to: display, via a graphical user interface on a user device, an entity model designer tool having a plurality of components including an entity composition function; responsive to an instruction from a user on the user device to model an entity in the entity model designer tool: generate a first view, the first view containing a name of the entity and the entity composition function; and display the first view on the graphical user interface; responsive to user interaction with the entity composition function in the first view: access the data store over a network; retrieving at least one entity building block of the plurality of entity building blocks from the data store; generate a second view, the second view including a collection of the at least one entity building block retrieved from the data store; and display the second view on the graphical user interface; and responsive to the user selecting a first entity building block from the collection of the at least one entity building block to add to the entity, the first entity building block comprising code instantiated from a class to implement one or more settings, automatically extending the entity to include the one or more settings of the first entity building block, the one or more settings including at least one of a property, a permission, an action, a behavior, or a resource to the entity.