Schematic illustration of the code structure of PyGRO. The Metric object serves as the primary symbolic tool in PyGRO, computing all tensorial quantities required for deriving geodesic equations. The GeodesicEngine, on the other hand, is responsible for the numerical integration of these equations, acting as a worker that processes Geodesic objects. These objects encapsulate the geodesic type (e.g., null or time-like) and properly normalized initial conditions (initial coordinates and initial tangent four-vector to the geodesic), and they receive the integration results. Higher-level APIs in PyGRO, such as the Observer or the Orbit, comprising both symbolic and numerical calculations, provide a more physically intuitive approach to initializing geodesics.