GuixSD fails to display login prompt on headless server

This was working in (GNU Guix) 0.13.0.4589-74bea6
ae0307f7c tests: Adjust to new unbound-variable error message.

It fails in guix (GNU Guix) 0.13.0.5042-6e385.
6e385b76e gnu: mongodb: Use scons-build-system.

System Generation on g1:
     19            GNU with Linux-Libre 4.14.2 (beta)           61 2017-11-30 19:18:15
     18            GNU with Linux-Libre 4.13.12 (beta)          62 2017-11-11 13:05:56

I just noticed this or I would have reported sooner.

Can check/test on either generation if it would be of help.

TIA - George

config: