nanoCAD

QCAD is a free, open-source application for computer-aided drafting (CAD) in two dimensions (2D). With QCAD you can create technical drawings such as plans for buildings, interiors, mechanical parts or schematics and diagrams. QCAD works on Windows, macOS, and Linux. The source code of QCAD is released under the GPL version 3 (GPLv3), a popular Open Source license. QCAD was designed with modularity, extensibility and portability in mind. But what people notice most often about QCAD is its intuitive user interface. QCAD is an easy-to-use but powerful 2D CAD system for everyone. You don't need any CAD experience to get started with QCAD immediately. Construction and modification of points, lines, arcs, circles, ellipses, splines, polylines, texts, dimensions, hatches, fills, and raster images. Very complete and extremely powerful ECMAScript (JavaScript) scripting interface. Various powerful entity selection tools.

LibreCAD is a free Open Source CAD application for Windows, Apple and Linux. Support and documentation are free from our large, dedicated community of users, contributors and developers. LibreCAD started as a project to build CAM capabilities into the community version of QCad for use with a Mechmate CNC router. Since QCad CE was built around the outdated Qt3 library, it had to be ported to Qt4 before additional enhancements. This gave rise to CADuntu. The project was known as CADuntu only for a couple of months before the community decided that the name was inappropriate. After some discussion within the community and research on existing names, CADuntu was renamed to LibreCAD. Porting the rendering engine to Qt4 proved to be a large task, so LibreCAD initially still depended on the Qt3 support library. The Qt4 porting was completed eventually during the development of 2.0.0 series, thanks to our master developer Rallaz, and LibreCAD has become Qt3 free except in the 1.0.0 series.