It took me an entire afternoon to set up a development environment for FreeCAD.
...so I'm publishing the ready made environment including kdevelop as a virtual machine.
For use with VirtualBox but the HDD is compatible with qemu.
The best option to extend the disk space is to add a second, virtual disk and mount it as /home/freecad/source or similar.
If there are issues where a (X)_python3.3.cmake file cannot be found, it may be required to change "python3.3" to "python2.7" via sudo in the respective (X).cmake file.