LibreDWG 0.13.3 GNU LibreDWG is a free C library to handle DWG files. It aims to be a free replacement for the OpenDWG libraries. DWG is the native file format of AutoCAD. GNU LibreDWG is based on LibDWG, originally written by Felipe Castro. GambasCAD viewer 0.0.10 A DXF, DWG file viewer that integrates to the desktop.