Info:

• 2000s: correct for the decade (plural of years).

  “Music from the 2000s.”

• 2000’s: only correct if showing possession.

  “The 2000’s biggest trend was…” .

Info:

nixos-rebuild switch = build the new system configuration (from /etc/nixos/configuration.nix or flakes) and activate it immediately without reboot.

• It builds the new system in /nix/store.
• Updates the GRUB/systemd-boot entries.
• Switches to the new configuration right away (systemd units, services, kernel params if possible, etc.).
• Leaves the old generations available for rollback (nixos-rebuild switch --rollback).

So: "switch" means build + activate now

Good text 👍 Faster to read through than it looks. The result probably is that we just don't exist 🙂

Why did the first thing happen on its own though?

Trying to sleep

All of them

Thanks for putting so much effort in your answer. If you think about it, it's kinda scuffed and you either end with existence is not possible or there was an action that was not caused by one. Just like you said.