1
0
Fork 0
nix-configuration/modules/nixos/system/nix/default.nix
2024-12-18 21:49:16 +00:00

100 lines
3 KiB
Nix

# Core Nix configuration
{
config,
inputs,
lib,
pkgs,
namespace,
system,
...
}:
let
cfg = config.${namespace}.nix;
nixos-operations-script = pkgs.writeShellScriptBin "nixos-operations-script" (
builtins.readFile (lib.snowfall.fs.get-file "bin/nixos-operations-script.sh")
);
in
{
options.${namespace}.nix = {
retention = lib.mkOption {
description = "How long to retain NixOS generations. Defaults to two weeks.";
type = lib.types.str;
default = "14d";
};
nixos-operations-script.enable = lib.mkEnableOption "Installs the nos (nixos-operations-script) helper script.";
};
config = lib.mkMerge [
{
nix = {
# Ensure we can still build when secondary caches are unavailable
extraOptions = ''
fallback = true
'';
settings = {
# Enable Flakes
experimental-features = [
"nix-command"
"flakes"
];
# Set up secondary binary caches for Lix and Hevana
substituters = [
"https://cache.lix.systems"
"https://${config.${namespace}.secrets.services.binary-cache.url}"
];
trusted-public-keys = [
"cache.lix.systems:aBnZUw8zA7H35Cz2RyKFVs3H4PlGTLawyY5KRbvJR8o="
config.${namespace}.secrets.services.binary-cache.pubcert
];
# Authentication for Hevana's binary cache
netrc-file =
with config.${namespace}.secrets.services.binary-cache;
pkgs.writeText "netrc" ''
machine ${url} login ${auth.username} password ${auth.password}
'';
# Only allow these users to use Nix
allowed-users = with config.users.users; [
root.name
(lib.mkIf config.${namespace}.users.aires.enable aires.name)
(lib.mkIf config.${namespace}.users.gremlin.enable gremlin.name)
];
# Avoid signature verification messages when doing remote builds
trusted-users = with config.users.users; [
root.name
(lib.mkIf config.${namespace}.users.aires.enable aires.name)
];
};
# Optimize the Nix store on each build
settings.auto-optimise-store = true;
# Enable garbage collection
gc = {
automatic = true;
dates = "weekly";
options = "--delete-older-than ${cfg.retention}";
persistent = true;
randomizedDelaySec = "1hour";
};
# Configure NixOS to use the same software channel as Flakes
registry.nixpkgs.flake = inputs.nixpkgs;
nixPath = [ "nixpkgs=${inputs.nixpkgs}" ];
};
# Support for standard, dynamically-linked executables
programs.nix-ld.enable = true;
}
(lib.mkIf cfg.nixos-operations-script.enable {
# Enable and configure NOS
${namespace}.packages = [ nixos-operations-script ];
environment.variables."FLAKE_DIR" = config.${namespace}.secrets.nixConfigFolder;
})
];
}