You can use @cabalbot to control / get info from an Arduino connected to the serialport.
Type @cabalbot HELP into a cabal to see a list of commands -- the @cabalbot will do your bidding!
Install cabal-headless and serialport via npm:
npm install cabal-headless
npm install serialport
Load the code in soil_bot_firmware onto an Arduino-compatible device.
You'll also need to install the Arduino-SerialCommand library.
After installing the library and loading the firmware, note what serialport the Arduino ends up on; this is hard-coded into soil.js on line 5 (you should change it to match your system):
const port = new SerialPort('/dev/ttyACM0')
The cabal key for the bot is also hard-coded into soil.js on line 16 (change it to match your cabal):
var key = 'cabal://0201400f1aa2e3076a3f17f4521b2cc41e258c446cdaa44742afe6e1b9fd5f82'