sub set_config_value {
  my($config, $name, $value) = @_;
  my @nesting = split /-/, $name;
  while (@nesting > 1) {
    my $field = shift @nesting;
    # make sure the next level is initialized to a hashref
    $config->{$field} //= {};
    # now point to it
    $config = $config->{$field};
  }
  # store at the bottom level
  $config->{$nesting[0]} = $value;
}
# use like this:
set_config_value(\%config, "address-virtual-email", "rpaskudniak");