I installed “HARK” in ubuntu 16.04 but while launching it I got the following error: 
PORT=3000
.warn:    –minUptime not set. Defaulting to: 1000ms
warn:    –spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms
../usr/lib/hark-designer/node_modules/xmlbuilder/lib/index.js:5
  ({assign, isFunction} = require(‘./Utility’));
   ^
ReferenceError: Invalid left-hand side in assignment
    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.<anonymous> (/usr/lib/hark-designer/node_modules/xml2js/lib/xml2js.js:12:13)
    at Object.<anonymous> (/usr/lib/hark-designer/node_modules/xml2js/lib/xml2js.js:388:4)
    at Module._compile (module.js:410:26)
error: Forever detected script exited with code: 1