Install #Arduino and #ESP32 Arduino core:
see https://www.arduino.cc
For Linux I downloaded https://downloads.arduino.cc/arduino-...
mkdir arduino
cd arduino
cp ~/Downloads/arduino-1.6.12-linux64.tar.xz .
tar xJf arduino-1.6.12-linux64.tar.xz
cd arduino-1.6.12/
./install.sh
see https://github.com/espressif/arduino-...
https://github.com/espressif
https://github.com/espressif/arduino-...
cd hardware
mkdir espressif
cd espressif
git clone https://github.com/espressif/arduino-... esp32
cd esp32/tools
python get.py