Kind of. I have plenty of spare hard drives lying around from curb-dumped hardware. But what I do not have is a single large hard drive in my laptop. So normally with Debian I have Debian 12.4, for example, on a spare drive, which was dd’d from a 90gb ISO. It’s a full blown installation disk plus all official apps. Then whenever I need to install an app I can USB-attach that drive, mount, and do apt install $newapp.

I am not familiar with nixOS, but I assume that is what you are talking about. So I guess the question is: would it be practical to create (on a separate spare drive) a cache of all nixOS official apps, all with interoperable version numbers that match whatever release I am running?

Does it count if you can bring your laptop to the library and run nix-env -i?

AFAIK, it’s possible with any distro to go to the library every time an app needs to be installed. That’s what I’m looking to avoid. I want the whole collection of interoperable versions of officially supported apps on a disk. Then I can spontaniously install something without a working connection. When I go to the library for any reason, I can opportunistically build an updated release.

Another part of this is having multiple machines (some of which are too big to bring to the library). The install disk requires 1 fetch of emacs, for example, which can then be installed many times on offline machines.