Similar reflection, I ran `kitten __benchmark__ --render` in rune, the CPU time spent was 1:55. I ran the same in a libghostty based terminal emulator and spent 0:44 on CPU.

I say this only because yes you can do engineering to meet the benchmark without dropping to deeper systems layers, but closing the gap on efficiency is hard. I'm not saying this to be a downer on your project - an IDE and VTE in Go are a fun project to have around, but the blog post makes implied claims of equivalence with moderate investment - but I think that's limited to single benchmark chasing. I say this as a polyglot who's day job is a Go based program that would be far easier to optimize in a systems language.