One can even make it pretty with a simple prototyped function:

sub hpush(\%@) {
  my ($h,$k,$v) = (shift);
  $$h{$k} = $v while ($k, $v) = splice(@_, 0, 2);
}

# ... later
my %bighash = ( A => 1, B => 2, C => 3 );
hpush %bighash, B => 3, D => 4;
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