I’ll summarize: language implementations get faster over time. Young ones tend to be slow. Fil-C is a young implementation that still has lots of unoptimized things. Also, Fil-C being 2x slower than C means it’s already faster than many safe languages. And, for a lot of C use cases perf doesn’t matter as much as the hype suggests.

The fact that young implementations are slow is something that’s worth understanding even if you don’t care about fil-C. It suggests, for example, that if someone invents a new language and their initial implementation is slow, then you can’t use that fact to assume that it’ll be slow forever. I think that’s generally a useful lesson.

I care about performance a lot and Fil-C has gotten about 100x faster since the first prototype. It’ll keep getting faster.