{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.nix.gc;
in
{
###### interface
options = {
nix.gc = {
automatic = mkOption {
default = false;
type = types.bool;
description = "Automatically run the garbage collector at a specific time.";
};
dates = mkOption {
default = "03:15";
type = types.str;
description = ''
Specification (in the format described by
systemd.time
5) of the time at
which the garbage collector will run.
'';
};
options = mkOption {
default = "";
example = "--max-freed $((64 * 1024**3))";
type = types.str;
description = ''
Options given to nix-collect-garbage when the
garbage collector is run automatically.
'';
};
};
};
###### implementation
config = {
systemd.services.nix-gc =
{ description = "Nix Garbage Collector";
script = "exec ${config.nix.package}/bin/nix-store --gc ${cfg.options}";
startAt = optionalString cfg.automatic cfg.dates;
};
};
}