Mule 3.4 introduces new features to simplify SaaS integration and API publishing, streamline the enterprise runtime for scalability and performance, and add enhanced data mapping and flow debugging. Key features include a visual flow debugger, high availability for zero downtime scaling, automated documentation generation, accelerated and simplified data mapping with DataMapper, and automatic data model discovery and mapping generation with DataSense. The release also enables 100% uptime, scalability to thousands of runtimes, and performance of hundreds of thousands of transactions per second through Anypoint Fabric in hybrid environments.