Ask HN: Deploying a web app to a VPS in 2017

I am a looking to deploy a small web application to a VPS that I bought.

I was hoping to learn a bit about devops in the process (instead of relying on a PaaS like Heroku) but the ecosystem seems overwhelming. There seems to be a large number of moving parts - Docker, Kubernetes etc.

What are some of the simpler options to deploy web apps to a VPS?