An additional benefit of interpreted, I think, is to make plugins easier to distribute and incorporate. With a compiled language you’d need message passing or something.

JVM has real and virtual threads and arguably just as good if not better on all these points.

(I actually have/am writing a harness in Java fwiw, but mostly as a hobby/experimentation)

That actually don't like you're describing Python. I've been working on a couple JS/TS projects and it's like the models I use (Claude Sonnet and DeepSeek v4 Flash) continually struggle to do coherent work; I have to always keep close watch to reduce sloppiness. I go to Python and it's smooth sailing with minimal prompting (and reduced token burn) for acceptable outcomes.

aren't 3 and 4 a tradeoff though? Yes you have 3 but "decent performance" cannot be an extaled value as compared to "runs everywhere". If its used as a counter balance to 3 then it shouldn't be its own unique point basically saying 4 is true despite 3 in this case.

decent performance, lol! compared to what? a shell script? "i'll only take up 200MB of disk and 4GB of RAM to output flickering text on a terminal. boy this is high performance"

fast iteration is for POCs. once you have the app built and working, you need performance and stability much more than fast iteration

Also isn't OpenAI's Codex written in Rust?

Python basically requires containers unless you are OK with it bit-rotting every six months or so. At least, this used to be the case for trivial python, and recently was the case for stuff that uses cuda.

I stopped paying attention the third time they redefined matrix arithmetic semantics. That happened to be around the 100th time I was sent a script and it only ran on the author’s machine. Maybe they will fix it some day. When they do, I will not believe it.

In contrast, TS has a much nicer type system and better async support. It runs well on web, mobile, desktop and server. Yes, sometimes you have to ship node.js or a whole web browser, but the tooling for that is slightly less insane than the analogous tooling for python.

Its language interoperability story is slightly nicer too (invoke native code, or use wasm). It’s UI story is much, much better since it reuses all the web stuff.

Pip practically invented the supply chain attack; npm perfected it. That’s probably a draw.

Of course, if you care about performance, then other choices make more sense. If you’re training a model then python probably still wins, but very few customers have a $1M+ machine.

`uv` helps but it's new, and I don't think it has the same mindshare yet on "I just globally want to install this thing that needs an interpreter/runtime", so Python probably just doesn't come first to mind.

I'm interested in this but why those four separate languages

Edit: okay I read the code, it's actually four separate implementations

I always thought nodejs was a weird ringtone for CLI tools.

For web stuff, sure.

But for CLI, it never made sense to me. Especially when Python and Go exist.