6.4 Customizing the System-Wide Guix

If you’re running Guix System or building system images with it, maybe you will want to customize the system-wide guix it provides—specifically, /run/current-system/profile/bin/guix. For example, you might want to provide additional channels or to pin its revision.

This can be done using the guix-for-channels procedure, which returns a package for the given channels, and using it as part of your operating system configuration, as in this example:

(use-modules (gnu packages package-management)
             (guix channels))

(define my-channels
  ;; Channels that should be available to
  ;; /run/current-system/profile/bin/guix.
  (append
   (list (channel
          (name 'guix-science)
          (url "https://github.com/guix-science/guix-science")
          (branch "master")))
   %default-channels))

(operating-system
  ;; …
  (services
    ;; Change the package used by 'guix-service-type'.
    (modify-services %base-services
      (guix-service-type
       config => (guix-configuration
                  (inherit config)
                  (channels my-channels)
                  (guix (guix-for-channels my-channels)))))))

The resulting operating system will have both the guix and the guix-science channels visible by default. The channels field of guix-configuration above further ensures that /etc/guix/channels.scm, which is used by guix pull, specifies the same set of channels (see channels field of guix-configuration).

The (gnu packages package-management) module exports the guix-for-channels procedure, described below.

Procedure: guix-for-channels channels

Return a package corresponding to channels.

The result is a “regular” package, which can be used in guix-configuration as shown above or in any other place that expects a package.