When the command is received, the processor resets and enters the bootloader. The python script begins streaming a hex file over WiFi to the ESP8226, which relays it to the Arduino’s bootloader.

You don’t have to use the built-in IDE. You can simply right click on the processor and upload a hex file. Recent Arduino IDEs have an option to export a hex file, and that works with no problem.

There are many reasons to build your own Arduino circuit on a protoboard or a custom-designed printed circuit board. At the heart of the Arduino platform is an AVR microcontroller, in usual way you ...