McPhD is a small, simple neutrino Monte Carlo transport package. For more information, please see this wiki page on Github. Note on branches: you really want the philox branch, and someday soon, I'll get around to fixing things so that philox is the default/master.
Los Alamos National Security, LLC (LANS) owns the copyright to McPhD, which it identifies internally as LA-CC-10-121. The license is BSD 3-Clause.