XS: A programming language. Anywhere, anytime, by anyone

This language, README, website has been written by AI agents.

At one point, the author may have written a fair bit of code by hand (starting with a Crafting Interpreters project, and then adapting it recently using agents?). The commit history is very confusing.

The design of the VM is nearly identical to the clox interpreter in Crafting Interpreters. There's also a bit of Lua inspiration mixed in the instruction encoding.

Who is this language for? Who is the audience, and what does the author intend to convey to them?

There's a ton of features -- are they used consistently? We have function overloading and traits. We have optional type annotations and effects -- the effects are handled with a (fragile) multi-shot continuation implementation (at least copy Leijen or libmprompt! that code is out there, free to use, and robust!)

There are two parallel type inference systems in `src/types`. The type system which the language actually uses is not consistent yet (see e.g. `inference.c`: "recursive type: bind anyways")

With that being said, I'd take the cross platform claims with an extreme grain of salt ...

I don't buy "Anywhere, anytime, by anyone" - no language can be that. Different people and different projects have wildly different needs. It looks like it tries to provide a single binary offering most of the compiler, debugger, linter, etc. on "all" platforms. Noble goal in itself, useful for some cases, but utterly irrelevant for many (most?) projects. If I have already decided to work on Linus, I don't care about Windows compatibility. And why "by anyone"? If a language is optimized for school kids, it can not be optimal for serious professionals, and vice versa.

Perl developers that depend on XS [1] for extending their code's behavior will have a "lovely" time with this lol!

Here's an example https://github.com/adriaandens/XSamples/blob/master/XSamples...

[1] https://perldoc.perl.org/perlxs

The docs feel AI generated.

There are a lot of words related to language design like tree walk interpreter, algebraic effects, and semantic analyzer. But no real content about the language design, motivation, or what distinguishes it from other languages.

Also strange to start of the language introduction with an entire page dedicated to comments and how white space is handled.

If this was written by a human, I how it is taken as constructive criticism to consider what key points you want to convey before people bounce off of a page.

It’s a bit hard to tell what’s interesting about the language itself.

On the website, the standard library lacks a table of contents, but you can see what it has here:

https://github.com/xs-lang0/xslang.org/tree/main/src/app/doc...

https://github.com/xs-lang0/xs/blob/d9e11545685c29c054c50c52...

    Every other piece of
    * the old tier-1 dispatch JIT (the ~1500 lines of per-opcode helpers,
    * the jump-table dispatcher, the jit_rt_* runtime shims) was deleted
    * because benchmarks showed tier-2 dominated on every workload that
    * reached the JIT at all. */

Its emacs as a programming language.

Here's a lot of really nice features in this language (I really like the actor / nursery designs), but a GIL in 2026 feels like a massive weakness

Not to be confused with the amazing open source XS JavaScript engine. https://github.com/Moddable-OpenSource/moddable

Initially, the page looked very intriguing and the promises looked every fascinating. A whole DX toolchain in one binary? The binary can run in different systems? Only 3 MB? Then I read the comments here saying its ai slop, I lost all my interest now.

All the copy is entirely generated. I can't find any actual human associated with this thing.

At this point, it doesn't really matter what the language does, because the author and I have mutual respect. There is none.

I liked it. AI-generated or not, syntactic decisions are tasteful and the language itself checks all the important boxes.

Too bad that agentic world basically destroyed all programming languages that are not Python, Typescript or Rust.

Interesting idea. I've fantasized about doing something similar myself. Like someone else in this thread already said though, looks very generated, unfortunately.

> let is immutable (reassignment is a runtime error), var is mutable, and const is identical to let at runtime but signals intent.

Tells me all I need to know. Signalling my intent to call this garbage.