Solo founder working on 2 Shopify apps. I tried to keep my setup simple with almost no build process:
1. 1 dev VM, 2 prod VM. ~$30 / m
2. Python / Django apps hosted with docker compose
3. Git pull to prod, just reload gunicorn to deploy most of the time unless I need to add new python libraries
4. Auto backup db daily with a docker container. Weekly backup by digital ocean
No k8s for sure.