Seamly2D
Free and open source pattern design software
Seamly2D enables the design, reuse, and remix of digital sewing patterns for creating bespoke-fit, specialty-sized, and ready-to-wear-sized clothing. Users have the right to utilize, sell, share, and distribute their patterns in any way they choose.
* Downloads: https://seamly.net
* Support: https://forum.seamly.net
* Code: https://github.com/fashionfreedom/seamly2d
* License: GPLv3+