The only assumption you need to make is how the process went about, which was described by Jarred on a HN comment when the PR was first discussed: they had prompt that described exactly how things should be translated, for each "pattern" they were using in Zig, an appropriate equivalent was described in Rust. Zig and Rust are not that different, both are system languages and things can be done similarly in both languages, so architecture-wise I would think the exact same thing would work fine. I am not sure whether the LLM actually wrote a transpiler which just followed the rules, or if it did the job itself, since that information is not public yet, as far as I know, but my guess is that the LLM wrote a transpiler to do the job, then reviewed/fixed compilation issues, then fixed tests. And I'm pretty sure some human interaction was part of that as well.
>The only assumption you need to make is how the process went about, which was described by Jarred
This is not how the process went. This is how Jarred thinks it went, a huge difference.
>my guess is that the LLM wrote a transpiler to do the job
My guess is different. I think one agent translated code, another compiled it, feeding errors back into translator to fix. Then last agent modifies code to fix tests. All governed by a set of md files.
So now you've gone from making assumptions to making up wild stories territory. Well, the commit granularity isn't that of transpiler passes, and more importantly, it's completely irrelevant to how the majority of the code hasn't even been read by anyone.