TLAPYEN — The Last Program You'll Ever Need

A Rust proc macro that calls Claude Code at compile time to generate Rust code from natural language descriptions.

Your builds now require WiFi, determinism is a distant memory, and you've officially outsourced programming to an AI running inside rustc.

Installation

[dependencies]
tlapyen = { path = "../tlapyen" }  # or from crates.io if we ever get that desperate

You'll also need the Claude CLI:

npm install -g @anthropic-ai/claude-code

Yes, your Rust project now depends on npm. We're sorry. Actually, no we're not.

Usage

use tlapyen::tlapyen;

tlapyen!("Make a dog type with a name and age. Give it a method called \
          'something_interesting' that returns a string with a fun, \
          creative fact about the dog based on its name and age.");

fn main() {
    let dog = Dog {
        name: "Rover".to_string(),
        age: 5,
    };
    println!("{}", dog.something_interesting());
    // Prints: ...something? Every `cargo clean && cargo build` is a surprise.
}

How It Works

1. You write a natural language description in tlapyen!("...")
2. At compile time, the proc macro shells out to the claude CLI
3. Claude generates Rust code
4. The macro parses it and splices it into your program
5. You pray

Results are cached in target/tlapyen-cache/ so subsequent builds don't re-invoke Claude. Run cargo clean to wipe the cache and live dangerously.

FAQ

Is this a good idea?

Absolutely not.

Is this production-ready?

Define "production."

What about determinism?

lol

What if Claude generates bad code?

You'll get a compile error with Claude's raw output so you can refine your prompt. It's like pair programming, except your partner is a stochastic parrot running inside your build system.

What if I don't have internet?

Then you can't compile. Welcome to the future.

Does this work with cargo check?

Yes! It will dutifully call Claude just to check your types. Every. Single. Time. (Unless cached.)

Known Limitations

• Determinism: Each build might produce different code. Or not. Who knows.
• Build times: Now depend on Claude's API latency and mood.
• Reproducibility: "It compiled on my machine" has a whole new meaning.
• Offline builds: A contradiction in terms.

License

MIT — because even chaotic software deserves a permissive license.