PROBLEM
You may face .pioinit:13: Error in sourced command file: error when trying to execute and debug code, especially on a NUCLEO board.
SOLUTION
Running this on a Mac will not output the reason, but running on Arch Linux does. My case was that the NUCLEO had a low power setting, causing the debugger to throw the error. Please verify if the STM32 power jumper on your board is set to U5V instead of E5V. This prevents the debugger from running and should crash the process, resulting in the .pioinit:13: Error in sourced command file:`
