too slow?

[powerman]

I wonder why Go's bcrypt is 1.5 times slower than Perl's one? Look (I don't use shell's time for perl to exclude perl's startup time, which is much larger than Go's):

$ time bcrypt-tool hash '0123456789' 10
$2a$10$God/j.dxKvryLSZfCAziMuMeZBfV28Xu24G6liCxlQbCM3PNs17S.

real    0m0.073s
user    0m0.072s
sys 0m0.000s

$ perl -E '
    use Crypt::Eksblowfish::Bcrypt qw(en_base64 bcrypt);
    use Time::HiRes qw(time);
    $t=time;
    open my $rand, "<", "/dev/urandom" or die $!;
    16 == sysread $rand, my $salt, 16 or die $!;
    close $rand or die $!;
    say bcrypt("0123456789", q{$2a$10$}.en_base64($salt));
    say time-$t;
'
$2a$10$WgABAl2bimF7wAOpRebTL.FQdV4n8Ho0/cWA4pGas.PUKpQTbYAL6
0.0554509162902832

Well, to be 100% honest this Perl module is partially implemented in C, but, still, Go shouldn't be 1.5 times slower than C on such tasks, isn't it?