nightwatch.json

{
  "src_folders" : ["test"],

  "webdriver" : {
    "start_process": true
  },

  "test_settings" : {

    "default" : {
      "webdriver": {
        "port": 9515,
        "cli_args": [
          "--verbose"
        ]
      },
      "desiredCapabilities" : {
        "browserName" : "chrome",
        "loggingPrefs": {"driver": "INFO", "server": "OFF", "browser": "INFO"}
      }
    },
    "chrome" : {
      "webdriver": {
        "port": 9515,
        "cli_args": [
          "--verbose"
        ]
      },
      "desiredCapabilities" : {
        "browserName" : "chrome",
        "loggingPrefs": {"driver": "INFO", "server": "OFF", "browser": "INFO"}
      }
    },
    "firefox" : {
      "webdriver": {
        "port": 9515,
        "cli_args": [
          "--verbose"
        ]
      },
      "desiredCapabilities" : {
        "browserName" : "chrome",
        "loggingPrefs": {"driver": "INFO", "server": "OFF", "browser": "INFO"}
      }
    }
  }
}