Swap
Swap on NixOS is set with the option: swapDevices
. This will be in hardware-configuration-nix.
To remove all swap devices from NixOS you must therefore set
swapDevices = lib.mkForce [ ];
This will remove the swap partition/file from being included in /etc/fstab
If you are using GPT partitioning tables systemd-gpt-auto-generator(8)
will still mount your swap partition automatically.
You must therefore turn on attribute 63 on your partition in the partition table.
This can be done with gptfdisk or similar:
gdisk /dev/sda
x
a
<partition number>
63
<enter>
w