What does HackerNews think of piku?
The tiniest PaaS you've ever seen. Piku allows you to do git push deployments to your own servers.
Anyway, for those wanting to deploy more generic apps, that is why I initially wrote https://github.com/piku/piku - you still have to flash the OS (and rpi-imager does that with sane defaults these days), but once you're done you have Heroku-like deployments for any language runtime you install on the Pi.
I also have https://github.com/rcarmo/ground-init, a cloud-init like shim that simplifies setting up machines (I'm a big fan of cloud-init, but since Raspbian doesn't support it and Ubuntu on ARM requires some fiddling to make it work I decided it wasn't too hard to roll my own).
(I probably should look into glueing that into rpi-imager, but there is are only so many hours in the day...)
Started as a hack, turned into the standard way of how I deploy all my personal projects, and then some.
I still use docker-compose and have a k3s cluster running, but I really like the simplicity of deploying via git.
Cloud-init for my core setups is here: https://github.com/piku/cloud-init