- [ ] #todo/b  Write overview of what ros2 does in my own words. Advantages / disadvantages

# Build System
The ROS2 [build system](https://docs.ros.org/en/humble/Concepts/Advanced/About-Build-System.html)is a challenging part, because packages written in different languages such as [[C++]] or [[Python]] need to be built together in order to form a unit.
To achieve this ROS2 relies heavily on the [[Colcon]] build system, which under the hood uses [[CMake]] for C++ packages and setuptools for Python. In order to define dependencies across the different packages and languages, ROS2 packages always contain a `package.xml` file also known as manifest file that contains essential metadata about the package, such as dependencies and others.