$ ./pre-inst-env guix system vm --no-grafts ~/work/guix/doc/os-config-bare-bones.texi 
Backtrace:
In ice-9/boot-9.scm:
1724: 19 [%start-stack load-stack ...]
1729: 18 [#<procedure 1503ea0 ()>]
In unknown file:
   ?: 17 [primitive-load "/home/leo/work/guix/scripts/guix"]
In guix/ui.scm:
1197: 16 [run-guix-command system "vm" ...]
In ice-9/boot-9.scm:
 157: 15 [catch srfi-34 #<procedure 3fa0880 at guix/ui.scm:421:2 ()> ...]
 157: 14 [catch system-error ...]
In guix/scripts/system.scm:
 882: 13 [#<procedure 3ed9210 at guix/scripts/system.scm:874:2 ()>]
 788: 12 [process-action vm # #]
In guix/store.scm:
1163: 11 [run-with-store # ...]
In guix/scripts/system.scm:
 800: 10 [#<procedure 46827e0 at guix/scripts/system.scm:792:8 (state)> #]
 564: 9 [perform-action vm # # ...]
In gnu/system/vm.scm:
 496: 8 [system-qemu-image/shared-store-script # # # ...]
In gnu/system.scm:
 601: 7 [operating-system-derivation # # #f]
In gnu/services.scm:
 573: 6 [loop #]
In srfi/srfi-1.scm:
 578: 5 [map #<procedure loop (sink)> (# # #)]
In gnu/services.scm:
 573: 4 [loop #<<service> type: # parameters: #>]
In srfi/srfi-1.scm:
 578: 3 [map #<procedure loop (sink)> (# # #)]
In gnu/services.scm:
 573: 2 [loop #<<service> type: # parameters: ()>]
In srfi/srfi-1.scm:
 578: 1 [map #<procedure 50635e0 at gnu/services.scm:562:4 (service)> (# # # # ...)]
In ice-9/eval.scm:
 416: 0 [urandom-seed-shepherd-service ()]

ice-9/eval.scm:416:20: In procedure urandom-seed-shepherd-service:
ice-9/eval.scm:416:20: Wrong number of arguments to #<procedure urandom-seed-shepherd-service ()>