The present invention extends to methods, systems, and computer program products for composing message processing pipelines. Embodiments utilize intra-pipeline communication links to physically and/or temporally decouple pipeline stages, configure branching message flows, and bridge protocols. The use of intra-pipeline communication links permits composition of a message processing pipeline without having to alter the pipeline components or application. Each communication link is itself an application with incoming and outgoing message processing pipelines that bridge messages across time and/or space and application logic for satisfying message processing requirements.