This repository provides the ROS 2 Middleware (RMW) implementation for eProsima Fast DDS, a high-performance DDS (Data Distribution Service) implementation. It translates the standard ROS 2 RMW API (publish, subscribe, services, clients, events) into Fast DDS operations, enabling ROS 2 nodes to communicate over DDS. The codebase is structured into three packages: `rmw_fastrtps_cpp` (static typesupport using compile-time code generation), `rmw_fastrtps_dynamic_cpp` (runtime introspection-based typesupport), and `rmw_fastrtps_shared_cpp` (shared logic for both variants). It supports advanced features such as content-filtered subscriptions, loaned messages, zero-copy data sharing via buffer backends (including GPU offloading), DDS security (PKI-DH, AES-GCM, access control), and comprehensive QoS mapping. The architecture follows a layered design where the shared package contains the core RMW implementations, and the two variant packages provide thin wrappers that differ only in how type support is resolved. This is a foundational infrastructure package for ROS 2, not an end-user application; it is selected at runtime via the `RMW_IMPLEMENTATION` environment variable.