This is funny. I am at the very moment side-by-side installing NixOS with Windows. And I am using two monitors. 1. The installer is Calamares. It's fantastic a

This is funny. I am at the very moment side-by-side installing NixOS with Windows. And I am using two monitors. 1. The installer is Calamares. It's fantastic and fully user-friendly, no need to worry about it. 2. I'll speak for KDE6 which I personally find superior to GNOME. You can have either with NixOS. I don't think there's anything specific to NixOS on multi-monitor functionality. There's a menu accessed either through a keyboard shortcut or system tray that allows any of the 5 permutations laptop/monitor. And it pops up as an OSD menu whenever you connect a monitor. I'd say the functionality is 'done'. 3. I suggest you read up on how Nix works, once you understand it you can understand NixOS better. To summarize, all programs in your system are stored in /nix/store and accessed through symlinks. You don't access /bin/bash, you access the bash executable stored in /nix/store through its symlink in your PATH. And all the symlinks are stored in a single directory. This directory is called a profile. There are multiple profiles. With NixOS, not only just executables but the system configuration data (users, passwords, mounted disks, desktop environment settings, traditionally in /etc) is also stored in profiles. This way you can have multiple 'whole system configuration's all containing different system configurations, arbitrary versions of arbitrary programs, and they don't conflict. During the boot, you can choose between different profiles. It's not limited to grub, systemd-boot also works.