electron-config default usage not working

index.js

const Config = require('electron-config');
const config = new Config();

config.set('unicorn', '🦄');
console.log(config.get('unicorn'));
//=> '🦄'

// use dot-notation to access nested properties
config.set('foo.bar', true);
console.log(config.get('foo'));
//=> {bar: true}

config.delete('unicorn');
console.log(config.get('unicorn'));
//=> undefined

package.json

{
  "name": "electron-config-test",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "electron": "^1.4.14",
    "electron-config": "^0.2.1"
  }
}