Without wanting to really move you from your strong opinions strongly held about Perl 6, is perf -especially numeric- actually prohibitively slow still? Have you done any numeric work in Perl 6 in say the last six months to a year? I'd gently suggest it's really not that bad anymore. Rational maths is always going to be slower than floating point due to hardware support. Comparing like for like though Im not sure the difference is so big its something that would stop me. At least if I was using something as slow as Perl 5 for numeric work to begin with perf is clearly not what I cared about! For the P6 advent this year I did a bit of a write up on my personal long wait for perf, its really not what it once was https://perl6advent.wordpress.com/2017/12/16/day-16-%F0%9F%8E%B6-deck-the-halls-with-perf-improvements-%F0%9F%8E%B6/