JS is not something that was developed with CLI in mind and on top of that that language does not lend itself to be good for LLM generation as it has pretty weak validation compared to e.g. Rust, or event C, even python.
Not to mention memory usage or performance.
I can’t find the tweet from Mario (the author), but he prefers the Typescript/npm ecosystem for non-performance critical systems because it hits a sweet spot for him. I admire his work and he’s a real polyglot, so I tend to think he has done his homework. You’ll find pi memory usage quite low btw.
Also python ones would also allow self modifying. I'm always puzzled (and worried) when JS is used outside of browsers.
I'm biased as I find JS/TS rather ugly language compared to anything other basically (PHP is close second). Python is clean, C has performance, Rust is clean and has performance, Java has the biggest library and can run anywhere.
It’s simply one of the most productive languages. It actually has a very strong type system, while still being a dynamic language that doesn’t have to be compiled, leading to very fast iteration. It’s also THE language you use when writing UIs. Execution is actually pretty fast through the runtimes we have available nowadays.
The only other interpreted language is Python and that thoroughly feels like a toy in comparison (typing situation still very much in progress, very weak ORM situation, not even a usable package manger until recently!).
You download one .py, run it and uv automatically downloads and installs any requirements to a virtual environment and runs it
I'm unsure that I agree with this, for my smaller tools with a UI I have been using rust for business logic code and then platform native languages, mostly swift/C#.
I feel like with a modern agentic workflow it is actually trivial to generate UIs that just call into an agnostic layer, and keeping time small and composable has been crucial for this.
That way I get platform native integration where possible and actual on the metal performance.