This National Science Foundation (NSF) Computer and Information Science and Engineering (CISE) federal Project Grant award to Duke University, with a total funding of $300,000 and a duration of 3 years (October 1, 2024 to September 30, 2027), supports the development of an Application Defined Networking (ADN) system to enable high-performance and efficient communication between microservices in cloud computing environments. The proposed work will create innovations across three key areas: (1) a declarative language to specify desired network functionality, (2) a compiler to translate the specified behavior into hardware and software configurations, and (3) a runtime system to dynamically optimize application performance. This research aims to address fundamental questions around the concise specification of application-level network behavior, efficient hardware-based network policy execution, and seamless application-level network upgrades. The project will advance the state-of-the-art in cloud computing infrastructure to reduce overheads, improve performance, and optimize resource utilization for microservice-based applications.