A system for developing software provides a graphical user interface on a display of a client device, the graphical user interface displaying features from a library of features for a custom software application, implements simulations of a plurality of the features available for demonstration through the graphical user interface, stores blocks of source code for each feature in a source code repository wherein the blocks are adapted to provide an actual application when compiled by developers, receives from the client device, by a server running a software building component, one or more selected features for the software application, automatically integrates, by the software building component, the one or more selected features to generate an integrated feature set based on attributes of each of the selected features and an inter-feature rules set, and generates an interactive visualization of a navigable prototype of the software application based on the integrated feature set.