Native assets
Native Assets are the Dart/Flutter build hooks mechanism for building and bundling native code assets. In flutter_rust_bridge, this is a compilation backend: it controls how the Rust library is built and packaged. It does not replace the core bridge code generator.
The flutter_rust_bridge Native Assets backend is available through --integration-backend native-assets.
Use flutter_rust_bridge_codegen >= 2.13.0-beta.2 and a Flutter/Dart SDK that supports build hooks and code assets.
Usage
Generate a project with:
flutter_rust_bridge_codegen create my_app --integration-backend native-assets
Or integrate into an existing project with:
flutter_rust_bridge_codegen integrate --integration-backend native-assets
The generated hook/build.dart uses flutter_rust_bridge_hooks.
That package currently wraps native_toolchain_rust, which compiles the Rust crate with Cargo and registers the result as a Dart/Flutter code asset.
If the project already has hook/build.dart, integrate preserves it and prints a warning instead of modifying it. Add FlutterRustBridgeNativeAssetsBuilder to the existing hook manually; see the generated hook from a new Native Assets project for the required call.
For existing projects that already use Cargokit, see Migrate from Cargokit to Native Assets.
Rust crate requirements
The Rust crate must be buildable by Cargo for the requested target platform.
For native_toolchain_rust, the crate needs a library target that can produce both static and dynamic artifacts:
[lib]
crate-type = ["staticlib", "cdylib"]
The crate also needs a rust-toolchain.toml that pins a concrete Rust toolchain and lists the supported targets.
Do not rely on a floating stable, beta, or nightly channel for reproducible build hooks.