My system configuration can be found on git.sr.ht/~sntx/flake. I’ve linked the file tree pinned to the version 0.1.1 of my config, since I’m currrently restructuring the entire config[^1] as the current tree is non-optimal[^2].
The documentation in the README in combination with the files should cover most of what I’ve described, with the following exception: disko is not present to the repo yet, since I’ve set it up with a forked version of my config and the merge depends on finishing the restructuring of my system configuration.
You can take a look at these (non-declarative) installation steps to get an idea on how TMPFS as root can be setup
If you’re interested, I can also DM you the disko expression for it
[^1]: The goal is to provide definitions for desktops, user-packages, system-packages, themes and users. Each system can then enable a set of users, which in turn have their own desktop, user-packages and theme. A system can also enable system-packages for itself, independent of users. If a user is enabled that has a desktop set, the system will need to have display-manager set as well, which should launch the users configured desktop.
[^2]: The current config assumes a primary user, and can only configure a single DE and apply the application/service configs only to that user.