As mentioned, the board is based on the Duet 3 Mini 5+ (https://github.com/Duet3D/Duet3-Mini5plus). While the main argument for removable drivers is the replace-ability on failure, why not avoid failure in the first place? The boards from Duet3D are widely regarded as reliable due to good design and having less failure points from using on-board drivers: proper PCB heatsinking, no chance of putting driver backwards, software-controlled stepper current. I've opted to inherit these in the design of this board.


Furthermore, as the sole developer, I have to choose where to put development effort and time. Using removable steppers would have introduced a layer of variability that was not present in the hardware this board is based on. Will users plug-in an SPI-based stepper? A UART-based one? RepRapFirmware would also require a rebuild upon changing drivers - which kinda defeats the purpose of RepRapFirmware's configure-by-gcode.