nix-files/hosts/modules/nixcache.nix

99 lines
3.5 KiB
Nix

# speed up builds from e.g. moby or lappy by having them query desko and servo first.
# if one of these hosts is offline, instead manually specify just cachix:
# - `nixos-rebuild --option substituters https://cache.nixos.org/`
#
# additionally, sends build jobs to servo/desko (splits the jobs across all that are enabled).
# to verify one particular remote builder:
# - `nix store ping --store ssh://servo`
# NOTE: if your unix user doesn't have ssh access to the remote builder, do the above as root (not just sudo, actual root).
# - `sudo su; nix store ping --store ssh://servo`
#
# future improvements:
# - apply for community arm build box:
# - <https://github.com/nix-community/aarch64-build-box>
# - don't require all substituters to be online:
# - <https://github.com/NixOS/nix/pull/7188>
{ lib, config, ... }:
with lib;
let
cfg = config.sane.nixcache;
hostName = config.networking.hostName;
in
{
options = {
sane.nixcache.enable = mkOption {
default = false;
type = types.bool;
};
sane.nixcache.enable-trusted-keys = mkOption {
default = config.sane.nixcache.enable;
type = types.bool;
};
sane.nixcache.substituters = let
subOpt = default: mkOption {
inherit default;
type = types.bool;
};
in {
nixos = subOpt true;
cachix = subOpt true;
};
sane.nixcache.remote-builders.desko = mkOption {
default = true;
type = types.bool;
};
sane.nixcache.remote-builders.servo = mkOption {
default = true;
type = types.bool;
};
};
config = {
# use our own binary cache
# to explicitly build from a specific cache (in case others are down):
# - `nixos-rebuild ... --option substituters https://cache.nixos.org`
# - `nix build ... --substituters ""`
nix.settings.substituters = mkIf cfg.enable (lib.flatten [
(lib.optional cfg.substituters.nixos "https://cache.nixos.org/")
(lib.optional cfg.substituters.cachix "https://nix-community.cachix.org")
]);
# always trust our keys (so one can explicitly use a substituter even if it's not the default).
# note that these are also used to sign paths before deploying over SSH; not just nix-serve.
nix.settings.trusted-public-keys = mkIf cfg.enable-trusted-keys [
"nixcache.uninsane.org:r3WILM6+QrkmsLgqVQcEdibFD7Q/4gyzD9dGT33GP70="
"desko:Q7mjjqoBMgNQ5P0e63sLur65A+D4f3Sv4QiycDIKxiI="
"nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
];
nix.buildMachines = [
(lib.mkIf cfg.remote-builders.desko {
hostName = "desko";
system = "x86_64-linux";
protocol = "ssh-ng";
maxJobs = 4; # constrained by ram, for things like webkitgtk, etc.
speedFactor = 8;
supportedFeatures = [ "big-parallel" ];
mandatoryFeatures = [ ];
sshUser = "nixremote";
sshKey = config.sops.secrets."nixremote_ssh_key".path;
})
(lib.mkIf cfg.remote-builders.servo {
hostName = "servo";
system = "x86_64-linux";
protocol = "ssh-ng";
maxJobs = 3; # constrained by ram, for things like webkitgtk, etc.
speedFactor = 2;
supportedFeatures = [
# "big-parallel" # it can't reliably build webkitgtk
];
mandatoryFeatures = [ ];
sshUser = "nixremote";
sshKey = config.sops.secrets."nixremote_ssh_key".path;
})
];
nix.distributedBuilds = lib.mkIf (cfg.remote-builders.desko || cfg.remote-builders.servo) true;
};
}