The title is obviously dishonest. I do not hesitate to call it a lie.

The post is also not about the speed increase, it's about how proud this team is of their agent orchestration scheme.

As I understand it, there is really no speed difference at all between Zig and C, just some cognitive overhead associated with doing things "right" in C. It's all machine code at bottom.

So why is this rewrite faster? Why did the authors choose Zig? How has the logic or memory management changed?

The authors give us absolutely no insight whatsoever into the the Zig code. No indication that they know anything about Zig, or systems programming, at all. I wish this was an exaggeration.

And really. With all this agentic power at your fingertips, why wouldn't they just contribute these improvements to git itself? I can think of at least one reason, that they don't want their changes to be rejected as unhelpful or low-quality.