This is the Delta 3D printer that has been an ongoing project for ~4 years. It:

• Uses the fabulous Duet 2 WiFi as a controller board, and Duet Smart Effector for calibration and mesh bed leveling.
• Has a homemade flexible magnetic bed for easy print removal.
• Uses a BondTech Extruder on a flying extruder mount (the green plate in the image). The flying extruder mount is this one found on Thingiverse.
• Has custom designed linear carriages to accommodate the flying extruder and the thicker than standard white timing belt