I think you need to pass a file-like object, not a scheme expression. Don't try to modify or interpret the public key file, just pass it directly as-is.

Le 16 janvier 2021 19:34:49 GMT-05:00, raingloom <raingloom@riseup.net> a écrit :
On Sat, 16 Jan 2021 07:10:47 +0100
Ricardo Wurmus <rekado@elephly.net> wrote:

raingloom <raingloom@riseup.net> writes:

guix archive --authorize started issuing a warning some time ago
pointing to "authorized-keys" in "operating-system".

* that is not a valid field of operating-system

That’s right. It’s a field of guix-configuration, which is documented
in 10.8.1 Base Services.


Thanks, I found that out already, that's how I ran into the other
issues.
I'm still confused about what the proper way to store the config info
is. Like how I should even store it as Scheme source code.