[2330] Setting new relic agent

I set a basic app with Nuxt and deployed on heroku. Now I would like to add the new relic agent (node js).

I have already a new relic profile, a license key for my application and and follow the new relic info: 1) Get your license key 2) add new relic package (done) 3) add a file in the root of the app, called "newrelic.js" and set it here the license key (done)

now next step i got troubles. they say : "Require New Relic. Make this the first line of your app's startup script" just add the code: require('newrelic');

Here i am not sure in which file I have to add this line and how to write it.

I suppose I should add it to nuxt.config.js and as first line. I did it and my app during the deploy is going in some loop and never ending.

I know I am doing something wrong, but not sure what. Suggestions? you can see the code here:

Maybe is a silly question and I am newbie, but I did not find any info about it ...

Thanks :)