Hi Ricardo and Alex,

Ricardo Wurmus <rekado@elephly.net> writes:

>> This error, in general shape, looks very much like an error I kept getting
>> when first "deploying" to a guix server. I found that doing a pull on the
>> server, followed by a system reconfigure then allowed me to actually
>> successfully run deploy afterwards.
>>
>> I'm not sure what causes that, but thought perhaps it was to do with
>> running an older version of guix on the target server before pulling?
>
> Thanks, it’s possible that this is in fact the case here.
>
> The error is really hard to diagnose, though, because there’s no file to
> inspect.  It would be good if “guix deploy” could catch errors stemming
> from the use of older Guixes on the target and throw a more instructive
> error message.

I saw this specific error message a few times while I was building 'guix
deploy'. It means something's been printed that can't be read, which
(might) be the case if something doesn't have a G-Expression compiler.
My money is on the target not having a reader for <operating-system>,
but as you've observed, the error reporting makes this incredibly
difficult to diagnose.

> @Jakob: What do you think?  Can we check for required Guix facilities on
> the remote and abort if they don’t exist?

I think that's a good idea, especially since we've had issues with
deploying to older Guixes before (with the 'user-homes' service).

Regards,
Jakob