Various examples are directed to systems and methods for implementing a web-based information system. A web application system may access a web application document that comprises object data, user interface data, and rule data. The web application system may serve the first user interface page to a first instance of a web application executing at a first user computing device, the first user interface page including first data object attributes of the first data object. The web application system may receive, through the first user interface page, a change to the first data object. The web application system may determine that the rule data describes a first action to be executed in response to the change to the first data object and execute the first action.