these 3 derivations will be built:
  /nix/store/dalglm3wk6d7k9jf83ppfr9xhipmbfa5-notmuch-vim-gems.drv
  /nix/store/craq28dk3hsphk7pv7m35ai8wal7bz61-notmuch-0.40.drv
  /nix/store/n7wj0cigk0pcrx8rd13461ad35jzwy67-msmtp.drv