$ guix pull
substitute: Backtrace:
substitute: In ice-9/boot-9.scm:
substitute:  160: 9 [catch #t #<catch-closure 56524aa17320> ...]
substitute: In unknown file:
substitute:    ?: 8 [apply-smob/1 #<catch-closure 56524aa17320>]
substitute: In ice-9/boot-9.scm:
substitute:   66: 7 [call-with-prompt prompt0 ...]
substitute: In ice-9/eval.scm:
substitute:  432: 6 [eval # #]
substitute: In ice-9/boot-9.scm:
substitute: 2412: 5 [save-module-excursion #<procedure 56524aa3a900 at ice-9/boot-9.scm:4084:3 ()>]
substitute: 4089: 4 [#<procedure 56524aa3a900 at ice-9/boot-9.scm:4084:3 ()>]
substitute: 1734: 3 [%start-stack load-stack ...]
substitute: 1739: 2 [#<procedure 56524aa4ebd0 ()>]
substitute: In unknown file:
substitute:    ?: 1 [primitive-load "/usr/bin/guix"]
substitute: In guix/ui.scm:
substitute: 1452: 0 [run-guix-command substitute "--query"]
substitute: 
substitute: guix/ui.scm:1452:12: In procedure run-guix-command:
substitute: guix/ui.scm:1452:12: In procedure setvbuf: Wrong type argument in position 1 (expecting port that supports 'setvbuf'): #<input-output: gnutls-session-port 56524b70bc30>
guix pull: error: corrupt input while restoring archive from #<closed: file 0>