Honest question. Do you recommend a "devcontainer" for this? Like a Docker image that maybe has both postgres and your development environment preinstalled inside? Or do you generally like to use and reference an external docker container instance (with postgres installed) and connect to it from your devcontainer instance?

I tend to use dev containers with docker compose.

So if I'm building Python application with Prometheus/RabbitMQ/PostGres that's used as part of my application, My docker compose has network, those 3 services + Python Dev Container and I just reference the hostname of the service in my Python application config (ENV VARS).

You can set it up with docker compose and put the container on the same network of your dev env, and you are good to go.

What I'd really like is an image that mirrors extensions available on AWS Aurora. Supabase's is the only that has some parity as far as I know