How to use pm2 to serve a Node.js app

pm2 is a super useful process management tool for Linux. I’ve used it for several projects of mine, and here I want to tell you how to use it too! In particular I’m going to use it to run a Node.js app on a DigitalOcean VPS, and I’ll set it up so that whenever we push an update to the app’s GitHub repository, on the server pm2 will be pinged, and the app is going to be updated from GitHub and restarted.