npub129gvast08lj986yftn7q5qlnj8yfqufxx0m33s9u5xssjm8c64rsve4kwg (npub129g…4kwg) Wow, those times are crazy! You could try SmallVec to shave off some ptr indirection still for the buckets (they don’t grow more than up to ~5–8 elements anyway…).
I guess I lose a lot of time on parsing here… (I’ve 87 µs for part1, 237 µs for part2 on my PC).