LinuxCNC

Opensource forum seems the most current.

https://www.rtai.org/

https://forum.linuxcnc.org/9-installing-linuxcnc

https://wiki.linuxcnc.org/cgi-bin/wiki.pl?LinuxCNCVersion2

https://linuxcnc.org/docs/2.8/html/getting-started/about-linuxcnc.html

http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Mechanical_Spreadsheet

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