What was the reason for omitting mailutils (and, specifically, a functional /usr/bin/mail binary) from the default strech install? That's kind of a standard thing to be there on *nix systems...
(Yes, I've just spent the last couple days wondering why a couple new stretch servers I set up were mailing some of their reports, but not others, and finally noticed the "/usr/bin/mail: not found" errors associated with the missing reports.) -- Dave Sherohman