PX4

Built around the uORB publish/subscribe middleware, enabling fully parallelized, thread-safe modules and highly customizable configurations as emphasized in the architecture section.

Supports a wide range of autopilot boards and sensors through the Pixhawk ecosystem, documented in the hardware support list and airframe reference.

Offers first-class MAVLink and DDS/ROS 2 integration, plus comprehensive SITL simulation and hardware-in-the-loop testing tools, facilitating efficient development and debugging.

Governed by the Dronecode Foundation under the Linux Foundation with a BSD license, ensuring open collaboration and no single-vendor control over the roadmap.