Cannot read property 'stack' of undefined on both the gomix and github project for basic node

I finished the Data viz beta certification and wanted to move on so I went on to the “Basic Node and Express” section.

I never tried gomix before but when I use the starter project I get a Cannot read property ‘stack’ of undefined and even if I input console.log(‘Hello World’) it won’t pass the test on the beta page.

I decided that gomix wasn’t worth spending time on so I moved on to the github repo, cloned it, ran ‘npm start’ and get the same Cannot read property ‘stack’ of undefined

Here is the full stack trace :

Hello World
TypeError: Cannot read property 'stack' of undefined
    at Object.setupBackgroundApp (/Users/Home/github/basic_node/node_modules/fcc-express-bground/index.js:149:31)
    at Object.<anonymous> (/Users/Home/github/basic_node/server.js:25:9)
    at Module._compile (module.js:541:32)
    at Object.Module._extensions..js (module.js:550:10)
    at Module.load (module.js:458:32)
    at tryModuleLoad (module.js:417:12)
    at Function.Module._load (module.js:409:3)
    at Module.runMain (module.js:575:10)
    at run (bootstrap_node.js:352:7)
    at startup (bootstrap_node.js:144:9)
Node is listening on port 3000...

And to add to that, how am I supposed to check if I can pass the tests ? Make a github page and put the url into the “yourapp.com” field in the challenge ?