Other than already mentioned backups I see no mention of: * staging environment for development * at least another baremetal machine for a copy of production and a loadbalancer in front of them, to prevent from 100% downtime in case your machine is down
The article wasn't about infrastructure or resilience, it was about technology stacks. Maybe those other things were there, maybe they weren't but it wasn't about what you should do, just what he did.
I don't find it fair to praise your tech-stack for simplicity and being cheap (awesome features btw) and fail to mention resilience. Unless you run a service that can be down 10% of time for example. Not the case here I guess since we talk about SaaS.