Nixpkgs
Nixpkgs
nixpkgs.flake.setFlakeRegistry
Whether to pin nixpkgs in the system-wide flake registry (/etc/nix/registry.json) to the
store path of the sources of nixpkgs used to build the NixOS system.
This is on by default for NixOS configurations built with flakes.
This option makes {command}nix run nixpkgs#hello reuse dependencies from the system, avoid
refetching nixpkgs, and have a consistent result every time.
Note that this option makes the NixOS closure depend on the nixpkgs sources, which may add undesired closure size if the system will not have any nix commands run on it.
Type: boolean
Default
"config.nixpkgs.flake.source != null"
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs-flake.nix
nixpkgs.flake.setNixPath
Whether to set {env}NIX_PATH to include nixpkgs=flake:nixpkgs such that <nixpkgs>
lookups receive the version of nixpkgs that the system was built with, in concert with
{option}nixpkgs.flake.setFlakeRegistry.
This is on by default for NixOS configurations built with flakes.
This makes {command}nix-build '<nixpkgs>' -A hello work out of the box on flake systems.
Note that this option makes the NixOS closure depend on the nixpkgs sources, which may add undesired closure size if the system will not have any nix commands run on it.
Type: boolean
Default
"config.nixpkgs.flake.source != null"
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs-flake.nix
nixpkgs.flake.source
The path to the nixpkgs sources used to build the system. This is automatically set up to be
the store path of the nixpkgs flake used to build the system if using
nixpkgs.lib.nixosSystem, and is otherwise null by default.
This can also be optionally set if the NixOS system is not built with a flake but still uses
pinned sources: set this to the store path for the nixpkgs sources used to build the system,
as may be obtained by builtins.fetchTarball, for example.
Note: the name of the store path must be "source" due to https://github.com/NixOS/nix/issues/7075.
Type: null or string or path
Default
"if (using nixpkgsFlake.lib.nixosSystem) then self.outPath else null"
Example
"builtins.fetchTarball { name = \"source\"; sha256 = \"sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=\"; url = \"https://github.com/nixos/nixpkgs/archive/somecommit.tar.gz\"; }"
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs-flake.nix
nixpkgs.buildPlatform
Specifies the platform on which NixOS should be built. By default, NixOS is built on the system where it runs, but you can change where it's built. Setting this option will cause NixOS to be cross-compiled.
For instance, if you're doing distributed multi-platform deployment, or if you're building machines, you can set this to match your development system and/or build farm.
Ignored when nixpkgs.pkgs is set.
Type: string or (attribute set)
Default
config.nixpkgs.hostPlatform
Example
{system = "x86_64-linux";}
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.config
Global configuration for Nixpkgs. The complete list of Nixpkgs configuration options is in the Nixpkgs manual section on global configuration.
Ignored when {option}nixpkgs.pkgs is set.
Type: nixpkgs config
Default
{ }
Example
{ allowBroken = true; allowUnfree = true; }
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.crossSystem
Systems with a recently generated hardware-configuration.nix
may instead specify only {option}nixpkgs.buildPlatform,
or fall back to removing the {option}nixpkgs.hostPlatform line from the generated config.
Specifies the platform for which NixOS should be
built. Specify this only if it is different from
nixpkgs.localSystem, the platform
on which NixOS should be built. In other
words, specify this to cross-compile NixOS. Otherwise it
should be set as null, the default. See its description in the
Nixpkgs manual for more details.
Ignored when nixpkgs.pkgs or hostPlatform is set.
Type: null or (attribute set)
Default
null
Example
{system = "aarch64-linux";}
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.hostPlatform
Specifies the platform where the NixOS configuration will run.
To cross-compile, set also nixpkgs.buildPlatform.
Ignored when nixpkgs.pkgs is set.
Type: string or (attribute set)
Default
(import "${nixos}/../lib").lib.systems.examples.aarch64-multiplatform
Example
{system = "aarch64-linux";}
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.localSystem
Systems with a recently generated hardware-configuration.nix
do not need to specify this option, unless cross-compiling, in which case
you should set only {option}nixpkgs.buildPlatform.
If this is somehow not feasible, you may fall back to removing the
{option}nixpkgs.hostPlatform line from the generated config and
use the old options.
Specifies the platform on which NixOS should be built. When
nixpkgs.crossSystem is unset, it also specifies
the platform for which NixOS should be
built. If this option is unset, it defaults to the platform
type of the machine where evaluation happens. Specifying this
option is useful when doing distributed multi-platform
deployment, or when building virtual machines. See its
description in the Nixpkgs manual for more details.
Ignored when nixpkgs.pkgs or hostPlatform is set.
Type: attribute set
Default
(import "${nixos}/../lib").lib.systems.examples.aarch64-multiplatform
Example
{system = "aarch64-linux";}
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.overlays
List of overlays to apply to Nixpkgs.
This option allows modifying the Nixpkgs package set accessed through the pkgs module argument.
For details, see the Overlays chapter in the Nixpkgs manual.
If the {option}nixpkgs.pkgs option is set, overlays specified using nixpkgs.overlays will be applied after the overlays that were already included in nixpkgs.pkgs.
Type: list of (nixpkgs overlay)
Default
[ ]
Example
[(self: super: {openssh = super.openssh.override {hpnSupport = true;kerberos = self.libkrb5;};})]
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.pkgs
If set, the pkgs argument to all NixOS modules is the value of
this option, extended with nixpkgs.overlays, if
that is also set. Either nixpkgs.crossSystem or
nixpkgs.localSystem will be used in an assertion
to check that the NixOS and Nixpkgs architectures match. Any
other options in nixpkgs.*, notably config,
will be ignored.
If unset, the pkgs argument to all NixOS modules is determined as shown in the default value for this option.
The default value imports the Nixpkgs source files
relative to the location of this NixOS module, because
NixOS and Nixpkgs are distributed together for consistency,
so the nixos in the default value is in fact a
relative path. The config, overlays,
localSystem, and crossSystem come
from this option's siblings.
This option can be used by applications like NixOps to increase
the performance of evaluation, or to create packages that depend
on a container that should be built with the exact same evaluation
of Nixpkgs, for example. Applications like this should set
their default value using lib.mkDefault, so
user-provided configuration can override it without using
lib.
Note that using a distinct version of Nixpkgs with NixOS may be an unexpected source of problems. Use this option with care.
Type: An evaluation of Nixpkgs; the top level attribute set of packages
Default
import "${nixos}/.." {inherit (cfg) config overlays localSystem crossSystem;}
Example
import <nixpkgs> {}
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix
nixpkgs.system
This option does not need to be specified for NixOS configurations
with a recently generated hardware-configuration.nix.
Specifies the Nix platform type on which NixOS should be built.
It is better to specify nixpkgs.localSystem instead.
{
nixpkgs.system = ..;
}
{
nixpkgs.localSystem.system = ..;
}
nixpkgs.localSystem for more information.
Ignored when nixpkgs.pkgs, nixpkgs.localSystem or nixpkgs.hostPlatform is set.
Type: string
Default
Traditionally builtins.currentSystem, but unset when invoking NixOS through lib.nixosSystem.
Example
"i686-linux"
Declared by: https://github.com/nixos/nixpkgs/blob/master/nixos/modules/misc/nixpkgs.nix