Credits, License, Source

Who made it

Tankun Sriket designs Xag. Claude writes the code.

That is the arrangement as it stands. The language, the syntax and what the project is for are his; the compiler, the runtime, the three engines, the oracle and this website are written by Anthropic's Claude under his direction. If that changes, this line changes with it.

Source

The compiler, the runtime, the engines and the oracle are at github.com/Artificial-IntelligenceAI/Xag-lang. Building from source is the way to run Xag; there is no install yet.

A diagnostic that is wrong, a diagnostic that is confusing, and a program Xag accepts that it should not are all the same kind of bug — the compiler saying something untrue — and they belong in the issue tracker.

This website has no public source. The site before it did: a Rust program compiled to WebAssembly, still readable at Xag-site, archived and no longer what this domain serves.

License

Copyright 2026 Tankun Sriket. Three projects, three answers, each chosen rather than inherited.

The compiler

Apache License, Version 2.0, with the LLVM exception — Apache-2.0 WITH LLVM-exception.

Writing programs in Xag costs you nothing. Every program the compiler builds has the Xag runtime linked into it, so a piece of the project ends up inside what you ship. The exception is there for exactly that: those embedded portions may be redistributed without carrying any notice, so a program built with Xag owes nothing to anybody and need not mention the project anywhere.

Changing Xag itself is where credit is due. Distribute a modified compiler, runtime or tool and the Apache terms apply in full — keep the notices, and say plainly which files you changed.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the project by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.

This website

Closed. All rights reserved. No permission is granted to copy, modify or redistribute any part of it.

Being closed hides the source, not the result. Everything this site is built from is served to every visitor as HTML, CSS and JavaScript and can be read there. What is closed is how it is put together.

The website before it

Apache-2.0 with one condition added: anything built on its code has to show the credit where its own readers can see it, not only in the source. The words on its pages were not licensed at all. That repository is archived and keeps those terms.

What it is built out of

The compiler

C++20, with C and a little assembly for the decimal hardware path and for a test that runs with no operating system under it, Rust for the oracle that fuzzes the three engines, Python for two test scripts, and shell to drive the one that needs a machine nobody here has — plus CMake, a linker script and the odd stand-in header to build all that. It is written against LLVM, whose licence exception it also borrows, and its grapheme handling comes from the Unicode Character Database, version 17.0.0.

The arithmetic is written against IEEE 754 and IBM's decimal specification, which are read rather than borrowed from. It is then checked against Python's decimal — libmpdec, by Stefan Krah — and against IBM's own decimal unit, emulated by QEMU and linked by ld.lld. Those two are there to disagree rather than to agree: neither is derived from anything here, which is the only reason their agreeing means anything.

This website

HTML, CSS and TypeScript, built by Vite and run through Node. One .html per page: no router, no framework, no prerender step. The CSS is written by hand, in one file. Cloudflare Pages serves it.

The playground is the compiler itself — its lexer, parser, checker, ownership pass, region pass and fast engine — compiled to WebAssembly by Emscripten, which is LLVM again. It runs in your browser and nothing you write there is sent anywhere.

The subset fonts below are cut with fontTools and compressed with Brotli.

Type

Three faces, each cut down to the characters this site actually uses and served from here, so none of them costs a request to anybody else or tells anybody else who is reading. All three are under the SIL Open Font License, Version 1.1.

• Public Sans — Copyright 2015 The Public Sans Project Authors. The site's default.
• Inter — Copyright 2016 The Inter Project Authors. The other choice in the bar.
• Orbitron — Copyright 2018 The Orbitron Project Authors, with Reserved Font Name "Orbitron". The wordmark, and nothing else. The cut-down file is named Xag Wordmark rather than Orbitron, because the licence reserves that name for the unmodified face and a subset is a modified one.

Colour

Two of the three themes are Solarized, by Ethan Schoonover, used at the values he published rather than adjusted to taste. Solarized Light's contrast is therefore his and not WCAG's — body text lands at 4.13:1 against base3 where AA asks for 4.5:1. Taking it down to base01 would pass and would stay inside the palette, but it would no longer be the thing it is named after.

Why would anyone ever use Xag?

Honestly, I don't know. 😂

The code written is mostly or 100% AI-made. Why? Because, I'm more of a designer, not a C++ stroke-inducing syntax reader 🤣. No offense.

— the README