SyntaxError: Unexpected token =

[chivalry123]

when I try to config kraken, i got this error, do you know what might have happen?
[email protected]:~$ coinx config kraken
/usr/local/lib/node_modules/coinx/node_modules/bitfinex-api-node/index.js:11
constructor (apiKey, apiSecret, opts = { version: 1, transform: false, nonceGenerator: false }) {
^

SyntaxError: Unexpected token =
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:374:25)
at Object.Module._extensions..js (module.js:417:10)
at Module.load (module.js:344:32)
at Function.Module._load (module.js:301:12)
at Module.require (module.js:354:17)
at require (internal/module.js:12:17)
at Object. (/usr/local/lib/node_modules/coinx/lib/bitfinex.js:4:13)
at Module._compile (module.js:410:26)
at Object.Module._extensions..js (module.js:417:10)
at Module.load (module.js:344:32)
at Function.Module._load (module.js:301:12)
at Module.require (module.js:354:17)
at require (internal/module.js:12:17)
at /usr/local/lib/node_modules/coinx/commands/coinx-core.js:29:20
at Array.forEach (native)