Multiple projects with the same services

[secobarbital]

I have the scenario that is highlighted in the README of having multiple projects, each with a database, except I need to start all of them at the same time to do e2e testing and debugging. How should I go about doing that?

I would like each project to use the default port when starting individually yet allow the user to easily customize the port used by the db or disable it and just use one of them, preferably without having to write nix code to do so.

Consider a scenario where we are juggling two projects, located at ~/code/foo and ~/code/bar. The foo project integrates postgres and nginx, while bar encompasses postgres, pgAdmin, and kafka. It's crucial that the postgres data remains segregated across these projects. Additionally, the bar project is designed to facilitate multiple instances of postgres. Both projects are equipped with a flake app, streamlining the launch of their respective service stacks. Consequently, anyone using a Linux or macOS system can effortlessly clone either project and execute nix run .#services to activate the full suite of services without the need for manual configuration.

[secobarbital]

One way to keep this sane is to have a "registry" flake for all the services across all the apps, that way it is clear which app's db is using which port and which app's redis is using which port.