Been improving my visual editor for compound graphs: https://grapherx.netlify.app/ . Recent additions: Undo/Redo, Multi-select, snap-to-grid, read-only mode etc. This tool is now being used by the Foresight institute for their civilizational tech trees for domains like nanotech, neurotech, spacetech, longevity research, intelligent cooperation: https://foresight.org/tech-tree/