New Developments in DD4hep

For a successful experiment, it is of utmost importance to providea consistent detector description. This is also the main motivation behindDD4hep, which addresses detector description in a broad sense including thegeometry and the materials used in the device, and additional parameters describing,e.g., the detection techniques, constants required for alignment andcalibration, description of the readout structures and conditions data. An integralpart of DD4hep is DDG4 which is a powerful tool that converts arbitraryDD4hep detector geometries to Geant4 and provides access to all Geant4 actionstages. It is equipped with a comprehensive plugins suite that includes handlingof different IO formats; Monte Carlo truth linking and a large set of segmentationand sensitive detector classes, allowing the simulation of a wide variety ofdetector technologies. In the following, recent developments in DD4hep/DDG4like the addition of a ROOT based persistency mechanism for the detector descriptionand the development of framework support for DDG4 are highlighted.Through this mechanism an experiment’s data processing framework can interfaceits essential tools to all DDG4 actions. This allows for simple integrationof DD4hep into existing experiment frameworks