error in execution

When I'm trying to execute app.js. I receive this error:

/cryptofaucet-node/processor.js:23
,next_run:(iz.required(config.processor_start) && iz.date(config.processor_start) ? new Date(config.processor_start) : null)
^

TypeError: iz.required is not a function
at Object. (/root/cryptofaucet-node/processor.js:23:17)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
at Module.require (module.js:497:17)
at require (internal/module.js:20:19)
at Object. (/root/cryptofaucet-node/app.js:27:14)
at Module._compile (module.js:570:32)