nixos/profiles/system.nix

   1 { config, pkgs, lib, inputs, ... }:
   2 with lib;
   3 {
   4   boot.tmp.cleanOnBoot = mkDefault true;
   5   boot.tmp.useTmpfs = mkDefault true;
   6   services.logrotate.enable = true;
   7   # NOTE: mostly useless on a server, and CPU intensive.
   8   documentation = {
   9     enable = mkDefault true;
  10     dev.enable = mkDefault false;
  11     doc.enable = mkDefault true;
  12     info.enable = mkDefault false;
  13     man.enable = mkDefault true;
  14     nixos.enable = mkDefault false;
  15   };
  16   programs.vim.defaultEditor = mkDefault true;
  17   environment.variables = {
  18     EDITOR = "vim";
  19     NIXPKGS_CONFIG = mkForce "";
  20     PAGER = "less -R";
  21     SYSTEMD_LESS = "FKMRX";
  22     # Setting TZ= avoids a lot of useless syscalls reading /etc/localtime
  23     # but requires to restart the session to change the time zone for all programs.
  24     TZ = lib.mkDefault (if config.time.timeZone != null then config.time.timeZone else "Europe/Paris");
  25   };
  26   home-manager.users.root = {
  27     imports = [
  28       ../../home-manager/options.nix
  29       ../../home-manager/profiles/essential.nix
  30     ];
  31     services.gpg-agent.pinentryPackage = pkgs.pinentry-curses;
  32   };
  33   nix = {
  34     settings.auto-optimise-store = mkDefault true;
  35     gc.automatic = mkDefault true;
  36     gc.dates = mkDefault "weekly";
  37     gc.options = mkDefault "--delete-older-than 7d";
  38     nixPath = mkForce [ ];
  39     # Pin the rev to the revision of the public Nixpkgs that the system was built from.
  40     # This is the version which will be locked by flakes using flake:nixpkgs
  41     #registry.nixpkgs = mkDefault { flake = inputs.nixpkgs; };
  42     registry.nixpkgs = {
  43       from = { id = "nixpkgs"; type = "indirect"; };
  44       to = {
  45         owner = "NixOS";
  46         repo = "nixpkgs";
  47         inherit (inputs.nixpkgs) rev;
  48         type = "github";
  49       };
  50     };
  51     package = pkgs.nixFlakes;
  52     settings.experimental-features = [ "nix-command" "flakes" "repl-flake" ];
  53   };
  54   security.lockKernelModules = false;
  55   services.journald = {
  56     extraConfig = ''
  57       Compress=true
  58       MaxRetentionSec=1month
  59       Storage=persistent
  60       SystemMaxUse=100M
  61     '';
  62   };
  63   # none is the recommended elevator for SSD, whereas HDD could use mq-deadline.
  64   services.udev.extraRules = ''
  65     ACTION=="add|change", KERNEL=="sd[a-z][0-9]*", ATTR{../queue/rotational}=="0", ATTR{../queue/scheduler}="none"
  66     ACTION=="add|change", KERNEL=="nvme[0-9]*n[0-9]*p[0-9]*", ATTR{../queue/rotational}=="0", ATTR{../queue/scheduler}="none"
  67   '';
  68   systemd.oomd = {
  69     enable = mkDefault true;
  70     enableRootSlice = mkDefault true;
  71     enableSystemSlice = mkDefault true;
  72     enableUserSlices = mkDefault true;
  73   };
  74   systemd.services.openssh = {
  75     serviceConfig = {
  76       ManagedOOMPreference = "omit";
  77     };
  78   };
  79   /*
  80     system.nixos.versionSuffix = ".${
  81     substring 0 8 (inputs.self.lastModifiedDate or inputs.self.lastModified)}.${
  82     inputs.self.shortRev or "dirty"}";
  83     system.nixos.revision = mkIf (inputs.self ? rev) inputs.self.rev;
  84   */
  85   # Let 'nixos-version --json' know about the Git revision of this flake.
  86   system.configurationRevision = mkIf (inputs.self ? rev) inputs.self.rev;
  87   /*
  88     system.configurationRevision =
  89     if inputs.self ? rev
  90     then inputs.self.rev
  91     else throw "Refusing to build from a dirty Git tree!";
  92   */
  93   users.mutableUsers = false;
  94 }