bug#45453: Error when I try to build a package using a JSON definition

[Ryan Prior via Bug reports for GNU Guix]

Hi guix! Today I wrote a package in Guile and then decided to try and
reproduce the same thing using JSON, but I hit a snag. I'm attaching
the package definition in its Guile and JSON forms, along with the error
I get when I try to build the package using `guix build -f countdown.json'.

Any idea what the issue here is or how I should go about debugging?

Thank you!
Ryan

countdown.scm
Description: Binary data

countdown.json
Description: application/json

Starting download of /tmp/guix-file.vO9g3u
From https://github.com/antonmedv/countdown/archive/v1.0.0.tar.gz...
following redirection to 
`https://codeload.github.com/antonmedv/countdown/tar.gz/v1.0.0'...
In procedure getaddrinfo: Name or service not known
failed to download "/tmp/guix-file.vO9g3u" from 
"https://github.com/antonmedv/countdown/archive/v1.0.0.tar.gz";
Backtrace:
In ice-9/boot-9.scm:
  1736:10 19 (with-exception-handler _ _ #:unwind? _ # _)
  1731:15 18 (with-exception-handler #<procedure 7f089852ec30 at ic…> …)
In guix/status.scm:
    780:4 17 (call-with-status-report _ _)
In ice-9/boot-9.scm:
  1736:10 16 (with-exception-handler _ _ #:unwind? _ # _)
In guix/store.scm:
   632:37 15 (thunk)
   1301:8 14 (call-with-build-handler #<procedure 7f089852e2d0 at g…> …)
In guix/scripts/build.scm:
    499:2 13 (_)
In srfi/srfi-1.scm:
   673:15 12 (append-map #<procedure 7f08966f20a0 at guix/scripts/b…> …)
   586:17 11 (map1 ((file . "countdown.json") (build-mode . 0) # # …))
In guix/scripts/build.scm:
   522:38 10 (_ _)
In guix/import/json.scm:
    90:21  9 (json->scheme-file _)
In ice-9/boot-9.scm:
  1731:15  8 (with-exception-handler #<procedure 7f0898531de0 at ic…> …)
In guix/import/json.scm:
    68:18  7 (_)
In srfi/srfi-1.scm:
   460:18  6 (fold #<procedure 7f0896697d68 at guix/import/json.scm…> …)
In guix/import/json.scm:
    77:54  5 (_ (("native-inputs" . #("go-github.com-mattn-g…" …)) …) …)
In guix/import/utils.scm:
   122:33  4 (alist->package (("native-inputs" . #("go-githu…" …)) …) …)
In ice-9/ports.scm:
   440:11  3 (call-with-input-file #f #<procedure 7f08973ad340 at g…> …)
In unknown file:
           2 (open-file #f "r" #:encoding #f #:guess-encoding #f)
In ice-9/boot-9.scm:
  1669:16  1 (raise-exception _ #:continuable? _)
  1669:16  0 (raise-exception _ #:continuable? _)

ice-9/boot-9.scm:1669:16: In procedure raise-exception:
Wrong type (expecting string): #f