Merge pull request #235011 from NixOS/before-23.05-final-release

system, [Hydra](https://hydra.nixos.org/).

* [Continuous package builds for unstable/master](https://hydra.nixos.org/jobset/nixos/trunk-combined)

* [Continuous package builds for the NixOS 22.11 release](https://hydra.nixos.org/jobset/nixos/release-22.11)

* [Continuous package builds for the NixOS 23.05 release](https://hydra.nixos.org/jobset/nixos/release-23.05)

* [Tests for unstable/master](https://hydra.nixos.org/job/nixos/trunk-combined/tested#tabs-constituents)

* [Tests for the NixOS 22.11 release](https://hydra.nixos.org/job/nixos/release-22.11/tested#tabs-constituents)

* [Tests for the NixOS 23.05 release](https://hydra.nixos.org/job/nixos/release-23.05/tested#tabs-constituents)

Artifacts successfully built with Hydra are published to cache at

https://cache.nixos.org/. When successful build and test criteria are

automatically from NixOS's Git repository after certain tests have

passed and all packages have been built. These channels are:

-   *Stable channels*, such as [`nixos-22.11`](https://nixos.org/channels/nixos-22.11).

-   *Stable channels*, such as [`nixos-23.05`](https://channels.nixos.org/nixos-23.05).

    These only get conservative bug fixes and package upgrades. For

    instance, a channel update may cause the Linux kernel on your system

    to be upgraded from 4.19.34 to 4.19.38 (a minor bug fix), but not

    Stable channels are generally maintained until the next stable

    branch is created.

-   The *unstable channel*, [`nixos-unstable`](https://nixos.org/channels/nixos-unstable).

-   The *unstable channel*, [`nixos-unstable`](https://channels.nixos.org/nixos-unstable).

    This corresponds to NixOS's main development branch, and may thus see

    radical changes between channel updates. It's not recommended for

    production systems.

-   *Small channels*, such as [`nixos-22.11-small`](https://nixos.org/channels/nixos-22.11-small)

    or [`nixos-unstable-small`](https://nixos.org/channels/nixos-unstable-small).

-   *Small channels*, such as [`nixos-23.05-small`](https://channels.nixos.org/nixos-23.05-small)

    or [`nixos-unstable-small`](https://channels.nixos.org/nixos-unstable-small).

    These are identical to the stable and unstable channels described above,

    except that they contain fewer binary packages. This means they get updated

    faster than the regular channels (for instance, when a critical security patch

    built from source than usual. They're mostly intended for server environments

    and as such contain few GUI applications.

To see what channels are available, go to <https://nixos.org/channels>.

To see what channels are available, go to <https://channels.nixos.org>.

(Note that the URIs of the various channels redirect to a directory that

contains the channel's latest version and includes ISO images and

VirtualBox appliances.) Please note that during the release process,

When you first install NixOS, you're automatically subscribed to the

NixOS channel that corresponds to your installation source. For

instance, if you installed from a 22.11 ISO, you will be subscribed to

the `nixos-22.11` channel. To see which NixOS channel you're subscribed

instance, if you installed from a 23.05 ISO, you will be subscribed to

the `nixos-23.05` channel. To see which NixOS channel you're subscribed

to, run the following as root:

```ShellSession

# nix-channel --list | grep nixos

nixos https://nixos.org/channels/nixos-unstable

nixos https://channels.nixos.org/nixos-unstable

```

To switch to a different NixOS channel, do

```ShellSession

# nix-channel --add https://nixos.org/channels/channel-name nixos

# nix-channel --add https://channels.nixos.org/channel-name nixos

```

(Be sure to include the `nixos` parameter at the end.) For instance, to

use the NixOS 22.11 stable channel:

use the NixOS 23.05 stable channel:

```ShellSession

# nix-channel --add https://nixos.org/channels/nixos-22.11 nixos

# nix-channel --add https://channels.nixos.org/nixos-23.05 nixos

```

If you have a server, you may want to use the "small" channel instead:

```ShellSession

# nix-channel --add https://nixos.org/channels/nixos-22.11-small nixos

# nix-channel --add https://channels.nixos.org/nixos-23.05-small nixos

```

And if you want to live on the bleeding edge:

```ShellSession

# nix-channel --add https://nixos.org/channels/nixos-unstable nixos

# nix-channel --add https://channels.nixos.org/nixos-unstable nixos

```

You can then upgrade NixOS to the latest version in your chosen channel

modules. You can also specify a channel explicitly, e.g.

```nix

system.autoUpgrade.channel = https://nixos.org/channels/nixos-22.11;

system.autoUpgrade.channel = "https://channels.nixos.org/nixos-23.05";

```