> What is the point of rewrite

To win a news cycle.

For the forseeable future, the AI market competition is not about which product can provide the most valuable utility to users. It's about which product can be holding the protective aura of social media and investment zeitgeist while competitors buckle under the strain from unfulfilled hype and over-leveraging.

Utility, engineering, efficiency... these are all menial details for the winners to reluctantly iron out in 2035.

Bun is fundamentally a boundary-heavy system and it also rolls its own version of a lot of things that people typically use via libraries, where unsafe is hidden. (no async, memory arenas, etc). It also uses FFI heavily which requires unsafe.

It also looks like the top 2 maintainers are currently actively working on getting the amount of unsafe down and it's going down quickly.

1. Rewrite from zig to rust in as close to zig as you can.

2. Turn into idiomatic rust.

unsafe just means that you take responsibility for the safety of the code contained within. Calling into non-Rust libraries has to be wrapped in unsafe. Making syscalls has to be wrapped in unsafe.

Bun needs to interact with FFI code. This gets wrapped in unsafe blocks.

There are many places where a JavaScript interpreter and library would need to make unsafe calls and operations.

It doesn't literally mean the code is unsafe. It means the code contained within is not something that can be checked by the compiler, so the writer takes responsibility for it.

There are many low-level data munging and other benign operations that a human can demonstrate are safe, but need to be wrapped in safe because they do things outside of what the compiler can check.

Some correct me if I'm wrong, but it's unlikely they wrote this first initial version of Rust and will leave it unchanged as-is. What's there now is a step in a long process, not the final destination.

The point is to serve as marketing for Claude. Absolutely nothing else.

Rust has a ton of other features besides safe. Like exhaustive checking of enum variants and the ability to avoid using null with option and result.