Open-source Radiative Modelling Tools for Extragalactic VHE gamma-ray Sources

In this review, we discuss various open-source software for modelling the broad-band emission of extragalactic sources from radio up to the highest gamma ray energies. As we provide an overview of the different tools available, we discuss the physical processes such tools implement and detail the computations they can perform. We also examine their conformity with modern good software practices. After considering the currently available software as a first generation of open-source modelling tools, we outline some desirable characteristics for the next generation.