%0Computer Program %TGriffin-m %XGriffin-m is a MOOSE-based reactor multiphysics application that streamlines the analysis of a variety of nuclear multiphysics simulations, including steady-state and transient radiation transport, core performance, fuel depletion, criticality and decay heat calculations, reprocessing and post-irradiation examination. This streamlining is accomplished via enhanced flexibility of the tools, uniform syntax in the MOOSE framework, dynamic linking of all relevant physics and a single point of execution. The design for flexible multi-physics, multi-radiation, multi-scheme tasks demands and ultimately makes Griffin-m a highly extendable code system. A software quality assurance (SQA) procedure is enforced during Griffin-m development. The Griffin-m version will be the main production version and it includes the MCC3 code, which was originally developed at Argonne National Laboratory to prepare cross sections for fast reactors. %AOrtensi, Javier %AWang, Yaqi %AHanophy, Joshua %ASchunert, Sebastian %APrince, Zachary %ACalvin, Olin %ALaboure, Vincent %AHarter, Jackson %AChoi, Namjae %AJung, Yeon %ALee, Changho %APark, Hansol %AKumar, Shikhar %Rhttps://doi.org/10.11578/dc.20231010.1 %Uhttps://www.osti.gov/doecode/biblio/114566 %CUnited States %D2021 %GEnglish %2USDOE Office of Nuclear Energy (NE) %1AC07-05ID14517 2021-07-27