QCAD - 2D CAD for Windows, Linux and Mac
The Open Source CAD System For Everyone
Main Features
Layers
Blocks (grouping)
35 CAD fonts included
Support for TrueType fonts
Various Metrical and Imperial units
DXF and DWG input and output
Printing to scale
Printing on multiple pages
Over 40 construction tools
Over 20 modification tools
Construction and modification of points, lines, arcs, circles, ellipses, splines, polylines, texts, dimensions, hatches, fills, raster images
Various powerful entity selection tools
Object snaps
Measuring tools
Part library with over 4800 CAD parts
Very complete and extremely powerful ECMAScript scripting interface
информация с
https://www.qcad.org/en/
интересен тем, что Open Source и кроссплатформенность
если на его основе навернуть надстройки по типу КАСАПР, будет очень отличный и годный продукт.