Each unique part geometry (drawing + rotation) is written once as a reusable sub-program called via M98, reducing output size for nests with repeated parts. G92 coordinate repositioning handles per-instance plate placement with restore after each call. Cut-offs remain inline. Controlled by UsePartSubprograms (default false) and PartSubprogramStart config properties. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>