GaitSym5 is the 2024 version of the GaitSym simulation system. It now has the option of using different physics engine backends for model validation and to take advantage of different engine specific features. There will be other, new features as time goes on. The current version is very much a work in progress and should be considered a technology preview more than anything else. The Master version should more of less work but is not feature complete. The development branch is not guaranteed to even compile.