gsl-lite https://github.com/EpicGames/zen/tree/main/thirdparty/ A single-file header-only implementation of ISO C++ Guidelines Support Library (GSL) for C++98, C++11 and later. https://github.com/gsl-lite/gsl-lite/blob/master/LICENSE Licensees Git P4 https://github.com/EpicGames/zen/tree/main/thirdparty/licenses