On 2020-10-21, Ludovic Courtès wrote:
> diff --git a/doc/guix.texi b/doc/guix.texi
> index c161012da5..50d2d9a730 100644
> --- a/doc/guix.texi
> +++ b/doc/guix.texi
...
> @@ -14583,6 +14598,27 @@ Whether to use substitutes.
>  @item @code{substitute-urls} (default: @code{%default-substitute-urls})
>  The list of URLs where to look for substitutes by default.
>  
> +Support you would like to fetch substitutes from @code{guix.example.org}

(substitute* "Support" "Suppose")

?

> +in addition to @code{@value{SUBSTITUTE-SERVER}}.  You will need to do
> +two things: (1) add @code{guix.example.org} to @code{substitute-urls},
> +and (2) authorize its signing key, having done appropriate checks
> +(@pxref{Substitute Server Authorization}).  The configuration below does
> +exactly that:
> +
> +@lisp
> +(guix-configuration
> +  (substitute-urls
> +   (append (list "https://guix.example.org")
> +           %default-substitute-urls))
> +  (authorized-keys
> +   (append (list (local-file "./guix.example.org-key.pub"))
> +           %default-authorized-guix-keys)))
> +@end lisp
> +
> +This example assumes that the file @file{./guix.example.org-key.pub}
> +contains the public key that @code{guix.example.org} uses to sign
> +substitutes.
> +
>  @item @code{max-silent-time} (default: @code{0})
>  @itemx @code{timeout} (default: @code{0})
>  The number of seconds of silence and the number of seconds of activity,