I just released firmware v0.2:

This release adds a dfu-bootloader (to enter press both buttons while plugging in, display will show "dfu") and a cascade controller (Two-step controller + PID, faster heating and less overshoot). Firmware is still shitty af ^^

dfu-utils usage:

dfu-util -a 0 -s 0x08000000:leave -D firmware.bin