GBuild is a set of makefile macros built on top of gmake that attempts to simplify LibreOffice development. See https://wiki.documentfoundation.org/Development/Build_System for online build-system documentation. See https://web.archive.org/web/20130911015536/http://wiki.openoffice.org/wiki/Build_Environment_Effort/Module_Migration for an archived overview of the new build system. See ./solenv/doc/gbuild for a commented class/API hierarchy of gbuild written in C++ syntax. It was not intended for any use beyond to generate nicelooking docs with the doxygen doxygen documentation generator from it. It likely is quite outdated these days.