The idea of the project is to develop IO routines adapted from Human Neocortical Neurosolver (HNN)-core objects while maintaining backwards compatibility with HNN-GUI. The requirement is to save various objects in newer formats while having capability to read both new and old formats. The proposed new format for HNN-core outputs is the Cross-language, flexible and binary format hdf5. It consists of groups (folder) and datasets (individual files) to store data modularly.