What are you guys/girls doing for debug? I don’t have an ST-Link (and I’m not sure I would know what to do with one). Is there a way to print back to USB connected term like there is in Arduino?
I have USB serial working in PlatformIO + Atom with the following platformio.ini settings:
[env:electrosmith_daisy]
platform = ststm32
board = electrosmith_daisy
framework = arduino
upload_protocol = dfu
build_flags = -w -D PIO_FRAMEWORK_ARDUINO_ENABLE_CDC -D USBCON -D
USB_MANUFACTURER="Unknown"
I don’t totally know what those settings do 
I yanked em from Difficulty with getting USB serial [USB CDC] working. Generally speaking, I have no idea what I am doing, but hopefully that might help!