🧱 native_toolchain_rs 🦀

---

Rust support for Dart's Native Assets.

Why native_toolchain_rs?

1. It's opinionated. That might sound bad, but it's opinionated in the way that keeps you from shooting yourself in the foot.
2. Does more with less. The API is incredibly easy to use: the only thing you need to provide is assetName, and the rest is auto-magically figured out. (But you can still tweak the functionality as much as you need to!)

Getting Started

1. Install rustup, for Rust, on your development computer (if you are a library author, consumers of your package will have to do the same)
2. Run flutter pub add native_toolchain_rs for Flutter or dart pub add native_toolchain_rs for Dart-only
3. (Until Native Assets is fully released) Switch to Flutter's beta channel: flutter channel beta
4. See Code Setup

Code Setup

native_toolchain_rs will look (by default) for native/ or rust/ (customizable) in your Dart package's root. If you haven't already, create a Cargo.toml and rust-toolchain.toml in your chosen Rust directory; keep reading for what these two files must contain (but don't worry if you forget, you'll get a helpful error message).

hook/build.dart

import 'package:hooks/hooks.dart';
import 'package:native_toolchain_rs/native_toolchain_rs.dart';

void main(List<String> args) async {
  await build(args, (input, output) async {
    await RustBuilder(
      assetName: 'src/my_ffi_bindings.g.dart',
      // ...maybe enable some Cargo features or something in here too
    ).run(input: input, output: output);
  });
}

Cargo.toml

Keep at least the following in your Cargo.toml.

[package]
name = "my-crate-name" # pick a name, doesn't matter

[lib]
crate-type = ["staticlib", "cdylib"] # THESE ARE IMPORTANT!

rust-toolchain.toml

Keep at least the following in your rust-toolchain.toml.

[toolchain]
# WARNING: *do not* use `stable`, `beta`, or `nightly` (alone) for the channel!
# You must specify a version number/date in order to ensure reproducible builds.
channel = "1.90.0" # or newer. another example: `nightly-2025-01-01`

# The targets you want to support; these are the default:
targets = [
  # Android
  "armv7-linux-androideabi",
  "aarch64-linux-android",
  "x86_64-linux-android",

  # iOS (device + simulator)
  "aarch64-apple-ios",
  "aarch64-apple-ios-sim",
  "x86_64-apple-ios",

  # Windows
  "aarch64-pc-windows-msvc",
  "x86_64-pc-windows-msvc",

  # Linux
  "aarch64-unknown-linux-gnu",
  "x86_64-unknown-linux-gnu",

  # macOS
  "aarch64-apple-darwin",
  "x86_64-apple-darwin",
]