Hi

I'm the maintainer of libredwg, and I was wondering if you are interested in better DXF and DWG support? libdxfrw is very limited in its DXF support, just the very basics. Reactors, xrecords and all the objects and relations to represent parametric constraints are missing. libredwg is able to that.
libdxfrw can read more versions, up to r2013, libredwg so far only up to r2007, and its DXF support is just in development. But libredwg can write DWG files and represent all advanced AutoCAD features.
https://github.com/LibreDWG/libredwg/
I'd just need a helping hand to rewrite and test the constraints parts for the start.

The first LibreDWG alpha release will come out soon, I'm just waiting for some GNU permissions to upload it at their site. And I'm finishing the DXF parts and the newer DWG versions.