This document describes a computing architecture that enables users to develop applications using building blocks that include micro frontends. In one aspect, a method includes providing a configuration user interface that enables a user to select and arrange building block user interface elements in a layout for a page. Data specifying a layout of one or more building block user interface elements that each include a micro frontend and corresponding backend logic is received from the configuration user interface. Each micro frontend includes one or more user interface components and a store that manages a model that represents a state of the one or more user interface components of the micro frontend. The corresponding backend for each micro frontend includes a function that updates the model of the micro frontend based on a previous model of the micro frontend and an action. User interface data is generated.