▻http://metapolator.com
Metapolator is a web-based parametric font editor.
It provides a GUI for designing with UFO fonts and Metafont – a language for semi-algorithmic specification of typefaces. Metapolator was created out of the need to create large font families efficiently.
▻https://github.com/metapolator/metapolator
Wow !
Metapolator turns any existing typeface into an intelligent type family system, so you can express yourself through its dials and sliders.
Its just like a cross-fader that mixes 2 turntables.
Again drawing a connection to the world of music productio, consider modular synthesizers, where stacks of modules (or masters, in our case) are linked in all possible ways.