[embedding-shape]

> The Rust rewrite passed 99.8% of the existing test suite. That number is enormous and significant, but let's be precise about what it actually says

I'm having a hard time even loading the PR, so can't look myself... But I seem to remember that there was changes to the test suite as well as the rewrite to the Rust engine, that would mean this number may or may not actually be accurate. Anyone remember or could actually load the PR and see? That'd make this article weirdly under-researched and missing something kind of vital.

[jottinger]

If I recall correctly - and I might not - the process found places in the test suite that were wrong or lacked clarity, and the suite was modified slightly in a few places to actually fix things that needed fixing. I don't think it was a broad enough change to actually significantly affect the coverage to a real degree, but then again, that WOULD be a good thing to dive into the PR to check - and as I've pointed out, I'm not a Bun user myself, so my main response to that is a vaguely-interested shrug and a nod towards what seems to be the bigger issue: the use of AI to do things performatively.

[kangalioo]

In what sense was Bun's rewrite performative? If I recall correctly, Jarred deliberately tried to fly a bit under the radar to prevent the inevitable outcry

[jottinger]

In the sense that while there was a positive outcome ("We moved to Rust, which solved our issues with Zig no longer accepting AI-assisted content" - a projection on my part, but one I think makes sense) without an actual contribution that one would expect.

It's in Rust! That means Rust's memory safety applies! ... except as a direct port, it doesn't, it's got Zig's memory semantics in Rust-shaped code. As others have pointed out (including me, FWIW) that's something that can change... but it's not a simple thing to accomplish, and it may ALWAYS be a Zig-shaped skeleton in a bag of Rust.

[pmxi]

This will load the PR easily: https://diffshub.com/oven-sh/bun/pull/30412