And the "high-performance" only really matters in inner loops. There's no reason why a programming language/development platform can't offer the best of both wo

And the "high-performance" only really matters in inner loops. There's no reason why a programming language/development platform can't offer the best of both worlds: the ability to write fast code where it matters (perhaps using type hints, etc.) and the ability to modify and redefine things at runtime. As long as you don't use those "dynamic" features in your inner loops, you are fine.