To use as a component of ESP-IDF

Download and install esp-idf
Create blank idf project (from one of the examples)

in the project folder, create a folder called components and clone this repository inside

mkdir -p components && \
cd components && \
git clone https://github.com/espressif/arduino-esp32.git arduino && \
cd .. && \
make menuconfig

make menuconfig has some Arduino options
- "Autostart Arduino setup and loop on boot"
  - If you enable this options, your main.cpp should be formated like any other sketch
```
//file: main.cpp
#include "Arduino.h"

void setup(){
  Serial.begin(115200);
}

void loop(){
  Serial.println("loop");
  delay(1000);
}
```
  - Else you need to implement app_main() and call initArduino(); in it.
    
    Keep in mind that setup() and loop() will not be called in this case. If you plan to base your code on examples provided in esp-idf, please make sure move the app_main() function in main.cpp from the files in the example.
```
//file: main.cpp
#include "Arduino.h"

extern "C" void app_main()
{
    initArduino();
    pinMode(4, OUTPUT);
    digitalWrite(4, HIGH);
    //do your own thing
}
```
- "Disable mutex locks for HAL"
  - If enabled, there will be no protection on the drivers from concurently accessing them from another thread/interrupt/core
- "Autoconnect WiFi on boot"
  - If enabled, WiFi will start with the last known configuration
  - Else it will wait for WiFi.begin
make flash monitor will build, upload and open serial monitor to your board