https://valentinaproject.bitbucket.io/

"Valentina is an open source pattern drafting software tool, designed to be the foundation of a new stack of open source tools to remake the garment industry.

Small-batch and custom-sized clothing manufacturing is essential to create a sustainable future, preserve small- to medium-sized textile spinning and weaving manufacturers, enable independent and small designers and manufacturers to scale up to make a decent living, rebuild local garment districts, and reduce or eliminate slave labour."

Join their forum at http://valentinaproject.forumotion.me/