Re: How to add custom channels to ISO

[Elais Player <elais@fastmail.com>]

You could add the custom channels file as an 
=extra-special-file=[1] in the =os-configuration=.

It would look something like this:

#+BEGIN_SRC scheme
(define %my-installation-os
  (operating-system
    (inherit installation-os)
    (services
     (cons*
      (extra-special-file
        "/etc/guix/channels.scm"
        (local-file "/path/to/my/channels.scm"))
      (operating-system-services installation-os)))))
#+END_SRC

Plus side is you now have a global channels file from which all 
you need to do is run =guix pull= to have all your channels up to 
date. You may also want to pin those channels to certain commits 
just in case. Down side is running =guix pull= will start filling 
up your disk or memory on an ISO and you can easily run out of 
space. (I would advise not running =guix pull= until after 
partitioning and setting up the target system), and this file will 
be added to the store (but if you're creating a channels file in 
=/etc= shouldn't matter honestly).

phodina via <help-guix@gnu.org> writes:

> Hello,
>
> I'm migrating to a newer machine and I'm taking my GuixSD 
> configuration with me.
>
> So the first logical step I did was to create an ISO image based 
> on this section [1]. As I use my custom channel with modified 
> packages I added them to the configuration to make them 
> available on the new machine.
>
> Or so I thought. I booted and partitioned the new machine then 
> ran
> guix system init /root/configurations.scm /mnt to install Guix 
> there.
>
> However, after reboot turns out that the packages are not from 
> my channel but from public Guix repository without 
> modifications.
>
> Therefore my question is if it's possible to specify also 
> channels in the configuration file so that they are used during 
> installation?
>
> Reading the manual I came to a nice command guix system describe 
> [2] which gives me the current configuration with the 
> channels. Could that be used to build an ISO which would then 
> also know about the additional channels?
> Kind regards
> Petr
>
> [1]: 
> https://guix.gnu.org/manual/en/html_node/Building-the-Installation-Image.html
> [2]: 
> https://guix.gnu.org/manual/en/guix.html#Invoking-guix-describe