An enterprise service bus (ESB) is a communication system between interacting software applications. FME Server was used as an ESB to solve the challenge of building a dynamic multi-page web form application for public data entry, validation and reporting that required complex spatial and non-spatial business rules. The solution used FME Server data streaming services and workspaces to dynamically provide JSON responses for the web front end content and perform form validation and interactions with backend services. Future improvements could make the process asynchronous to prevent page freezing if engine queues are busy.