Codex is written in rust, fyi... Not that I disagree.

Oh, I haven't been keeping up. I assumed it was still TS since it prompts me to run npm all the time.

They just use npm as a binary delivery mechanism, for whatever reason (I guess they expect all their users to have npm?)

It's pretty darn ubiquitous, yeah. Plus enterprises tend to run npm mirrors, so delivery integrates into existing IT compliance frameworks.

Which generates unnecessarily huge binaries.

It's because they statically linked it, and probably rely on a trillion pointless crates (as is standard in Rust development). A good statically linked harness can easily be ~5MB MAX