nix-files/modules/impermanence.nix

90 lines
3.4 KiB
Nix

# borrows from:
# https://xeiaso.net/blog/paranoid-nixos-2021-07-18
# https://elis.nu/blog/2020/05/nixos-tmpfs-as-root/
# https://github.com/nix-community/impermanence
{ lib, config, impermanence, ... }:
with lib;
let
cfg = config.colinsane.impermanence;
in
{
imports = [
# TODO: move to flake.nix?
impermanence.nixosModule
];
options = {
colinsane.impermanence.enable = mkOption {
default = false;
type = types.bool;
};
};
config = mkIf cfg.enable {
environment.persistence."/nix/persist" = {
directories = [
"/home/colin/archive"
"/home/colin/dev"
"/home/colin/ref"
"/home/colin/tmp"
"/home/colin/use"
"/home/colin/Music"
"/home/colin/Pictures"
"/home/colin/Videos"
# cache is probably too big to fit on the tmpfs
# TODO: we could bind-mount it to something which gets cleared per boot, though.
"/home/colin/.cache"
"/home/colin/.ssh"
# intentionally omitted:
# "/home/colin/.config" # managed by home-manager
# "/home/colin/.local" # nothing useful in here
# "/home/colin/.mozilla" # managed by home-manager
# creds. TODO: can i manage this with home-manager?
"/home/colin/.config/spotify"
# creds, but also 200 MB of node modules, etc
"/home/colin/.config/discord"
"/etc/NetworkManager/system-connections"
# "/etc/nixos"
"/etc/ssh"
# "/var/lib/AccountsService" # not sure what this is, but it's empty
"/var/lib/alsa" # preserve output levels, default devices
# "/var/lib/blueman" # files aren't human readable
"/var/lib/bluetooth" # preserve bluetooth handshakes
"/var/lib/colord" # preserve color calibrations (?)
# "/var/lib/dhclient" # empty on lappy; dunno about desko
# "/var/lib/fwupd" # not sure why this would need persistent state
# "/var/lib/geoclue" # empty on lappy
# "/var/lib/lockdown" # empty on desko; might store secrets after iOS handshake?
# "/var/lib/logrotate.status" # seems redundant with what's in /var/log?
"/var/lib/machines" # maybe not needed, but would be painful to add a VM and forget.
# "/var/lib/misc" # empty on lappy
# "/var/lib/NetworkManager" # looks to be mostly impermanent state?
# "/var/lib/NetworkManager-fortisslvpn" # empty on lappy
"/var/lib/nixos" # has some uid/gid maps; not sure what happens if we lose this.
# "/var/lib/PackageKit" # wtf is this?
# "/var/lib/power-profiles-daemon" # redundant with nixos declarations
# "/var/lib/private" # empty on lappy
# "/var/lib/systemd" # nothing obviously necessary
# "/var/lib/udisks2" # empty on lappy
# "/var/lib/upower" # historic charge data. unnecessary, but maybe used somewhere?
"/var/log"
# TODO: what even GOES in /srv?
"/srv"
];
files = [
"/etc/machine-id"
# "/home/colin/knowledge"
"/home/colin/.zsh_history"
# # XXX these only need persistence because i have mutableUsers = true, i think
# "/etc/group"
# "/etc/passwd"
# "/etc/shadow"
# { file = "/home/test2"; persistentStoragePath = "/nix/persist"; }
];
};
};
}