Comment by simonw
3 days ago
Alarmingly well! https://gisthost.github.io/?1bf98596a83ff29b15a2f4790d71c41d...
It couldn't quite beat the Rust implementation on everything, but it managed to edge it out on at least some of the benchmarks it wrote for itself.
(Honestly it feels like a bit of an afront to the natural order of things.)
That said... I'm most definitely not a Rust or C programmer. For all I know it cheated at the benchmarks and I didn't spot it!
Nice. Yeah I'd have to actually look at what it did. For the task of substring search, it's extremely easy to fall into a local optima. The `memchr` crate has oodles of benchmarks, and some of them are very much in tension with others. It's easy to do well on one to the expense of others.
But still, very neat.
Here's the C code. It pretty much lifted every optimization trick it could find directly from your Rust code, as far as I can tell: https://github.com/simonw/research/blob/main/memchr-c-wrappe...
What are you using to easily share the conversation as its own webpage? Very nice and tidy.
A Python tool called claude-code-transcripts that I had Claude Code help me write last month: https://simonwillison.net/2025/Dec/25/claude-code-transcript...
Very cool