Benchmark: running buk, index, regex for at least 5 CPU seconds...
       buk:  6 wallclock secs ( 5.31 usr +  0.01 sys =  5.32 CPU) @ 1973.50/s (n=10499)
     index:  5 wallclock secs ( 5.29 usr +  0.01 sys =  5.30 CPU) @ 3023.77/s (n=16026)
     regex:  6 wallclock secs ( 5.29 usr +  0.00 sys =  5.29 CPU) @ 931.00/s (n=4925)
        Rate regex   buk index
regex  931/s    --  -53%  -69%
buk   1973/s  112%    --  -35%
index 3024/s  225%   53%    --