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>> 2) Is it possible to use private remote repositories as channels?
>> The issue here seems to be one of authentication. I'm wonder if
>> there is (or should be) an "authentication" field one would add to
>> the channel definition in the channels.scm file.
>>
> I agree it would be nice to have. The git-fetch method is defined
> here:
> https://github.com/guix-mirror/guix/blob/012bf5c4c03e30633f137960bd0677e204c638a7/guix/build/git.scm
> and I think it can be modified without too much effort to include an
> argument for the -key flag to the git command. I am not sure though
> whether git-fetch will have access to the home user's directory in
> case you provide let's say ~/.ssh/id_rsa as argument. Another
> possibility would be to check the GIT_SSH_COMMAND env variable. I
> suppose you also need to make sure ssh is available for git-fetch.

Another way to use a private repo is oauth authentication.

(channel … (url "https://gitlab-ci-token:xxxxxxxxxxxxx-xxxxxx@gitlab.com/author/repository.git")