Most dactyl designs are parametric, meaning you measure your hands and the design is automatically created to adjust your hands.
Some subreddits that I know: r/ErgoMechKeyboards r/MechanicalKeyboards r/olkb
Also I know about these on Discord: SliceMK KBDFans BastardKB SplitKB QMK
Oh! looks like there's a OpenSCAD parametric dactyl now (1) I think this was the clojure one I was playing with before: (2)
[1] https://ohkeycaps.com/products/built-to-order-dactyl-manufor...