Node.js app crashing with an R10 error - node.js

Question

I am trying to successfully deploy a Node/React project on Heroku and after hours of debugging issues (I am a new developer) I think I got it near the finish line but now Heroku is posing some issues with deployment.
For background, here is my package.json file so you know what I have installed:
{
"name": "StarterApp",
"version": "1.0.0",
"engines": {
"node": "10.4.1",
"npm": "6.1.0"
},
"description": "",
"main": "index.js",
"scripts": {
"test": "mocha",
"dev": "node server.js",
"build": "next build"
},
"author": "",
"license": "ISC",
"dependencies": {
"express": "4.16.3",
"fs-extra": "^5.0.0",
"ganache-cli": "^6.1.3",
"mocha": "^5.2.0",
"next": "^4.2.3",
"next-routes": "^1.4.2",
"node-gyp": "^3.7.0",
"react": "^16.4.1",
"react-dom": "^16.4.1",
"rebuild": "^0.1.2",
"semantic-ui-css": "^2.3.2",
"semantic-ui-react": "^0.79.1",
"sha3": "^1.2.2",
"solc": "^0.4.24",
"truffle-hdwallet-provider": "0.0.3",
"web3": "^1.0.0-beta.34"
}
}
This is what I have in my server.js file:
app.prepare().then(() => {
createServer(handler).listen(5000, (err) => {
if (err) throw err;
console.log('Ready on localhost:5000');
});
This is what Heroku suggests the code to look like (source):
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
console.log(Our app is running on port ${ PORT });
});
The problem I am running into is that I am not sure how to merge what I already have with what Heroku wants me to use. My code is necessary so that it works with NextJS and the Heroku code is agnostic of that. What can I do to make the two work together? Thanks!

Answer 1

I figured it out it seems. I just did the following:
app.prepare().then(() => {
const PORT = process.env.PORT || 3000;
createServer(handler).listen(PORT, (err) => {
if (err) throw err;
console.log('Ready on localhost:5000');
});
Doing that allowed me to use both NextJS and Heroku suggested code.