Driving a NEMA11 stepper motor
I checked with an Arduino Nano and a ESP32 dev board and it worked with the wiring, driver, code and all. Since it felt quite reliable, I wondered about the discussion regarding the performance and tested it: I measured a torque of 4.5Ncm, which is close enough to the 6Ncm they claim in the datasheet. It seems that the D1 (or just the one I have) does not supply sufficient power!