Here's what jumped from my fingers...

use Data::Dumper;

my @array = 'a' .. 'w';
my $num = 3;                    # buckets

my $cnt = @array;               # total items
my $base = int($cnt/$num);      #  }
my $left = $cnt % $num;         #  } $cnt = ($base * $num) + $left

my @buckets;
for (1..$num) {
        push @buckets, [ splice(@array,0,$base + ($left-- > 0 && 1) ) 
+];
}

print Dumper(\@buckets);
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