Crate fm_bindings 

Foundation Models Bindings for Rust

Rust bindings for Apple’s Foundation Models framework, providing access to on-device large language models (LLMs) that power Apple Intelligence.

Requirements

• macOS 26+ or iOS 26+
• Apple Intelligence enabled in System Settings

Features

• Blocking Response: Get complete responses with response()
• Streaming Response: Get real-time incremental updates with stream_response()
• Type-safe error handling with Result<T, Error>
• Zero-copy FFI layer for optimal performance

Examples

Blocking Response

use fm_bindings::LanguageModelSession;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let session = LanguageModelSession::new()?;
    let response = session.response("What is Rust?")?;
    println!("{}", response);
    Ok(())
}

Streaming Response

use fm_bindings::LanguageModelSession;
use std::io::{self, Write};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let session = LanguageModelSession::new()?;

    session.stream_response("Tell me a story", |chunk| {
        print!("{}", chunk);
        let _ = io::stdout().flush();
    })?;

    println!(); // newline after stream
    Ok(())
}

Structs

LanguageModelSession

A session for interacting with Apple’s Foundation Models

Enums

Error

Errors that can occur when using Foundation Models

Type Aliases

Result

Result type alias for Foundation Models operations