Hub board for 36 stepper motors can be purchased here https://s.click.aliexpress.com/e/_DDC4dDn
This link is affiliated URL. If you purchase via link above it will give tiny cent of commission to the community organizers. (We are not Mellow employees, just 3D printer enthusiasts) This will not hurt your wallet and at the same time help us to maintain the GitHub better.
Hub board that can be mounted to the extruder motor
Scheme reference from Christoph Müller
Christoph Müller/voron_0_pancake_board
Thanks