nitro_annotations library

Classes

AndroidNativeImpl

Accepted by NitroModule.android.

AppleNativeImpl

Accepted by NitroModule.ios and NitroModule.macos.

CppImpl

Direct C++ via CMake/FFI. Valid on all native platforms. Implements all native-platform sealed interfaces so it is accepted by every NitroModule platform field except NitroModule.web.

HybridEnum

HybridRecord

Marks a Dart class as a rich, binary-serialized record type for use as method parameters, return types, or stream items in a @NitroModule.

HybridStruct

Value type that bridges with C-ABI struct layout.

KotlinImpl

Kotlin + JNI bridge. Valid on Android only.

LinuxNativeImpl

Accepted by NitroModule.linux.

MainThread

NativeImpl

Backward-compatible shorthand namespace. Prefer the per-platform constants (AppleNativeImpl, AndroidNativeImpl, WindowsNativeImpl, LinuxNativeImpl, WebNativeImpl) for clarity.

NitroAsync

NitroCustomType

Registers a Dart class as a custom FFI bridge type encoded by a NitroFfiCodec.

NitroEntryPoint

NitroFast

NitroModule

NitroNativeAsync

NitroOwned

Marks that the native side heap-allocates the returned NativeHandle and Dart takes ownership. The generator will:

NitroResult

Marks a method's return type as a discriminated success/error result.

NitroStream

NitroStreamBatch

@NitroStream with batch backpressure configuration. Example: @NitroStream(backpressure: Backpressure.batch, batchMaxSize: 64)

NitroTuple

Marks a Dart 3 positional record typedef as a named tuple type.

NitroVariant

Marks a Dart sealed class as a discriminated union type (sum type / tagged union).

SwiftImpl

Swift + @_cdecl bridge. Valid on Apple platforms (iOS and macOS) only.

WasmImpl

WASM/JS interop bridge. Valid on Web only — dart:ffi is unavailable on web.

WebNativeImpl

Accepted by NitroModule.web.

WindowsNativeImpl

Accepted by NitroModule.windows.

ZeroCopy

Enums

Backpressure

Constants

hybridRecord → const HybridRecord

mainThread → const MainThread

Runs the Kotlin/Swift implementation of this method on the platform's main/UI thread instead of the calling thread.

nitroAsync → const NitroAsync

nitroEntryPoint → const NitroEntryPoint

Marks a top-level Future<String> Function(String) (or String Function(String)) in the spec file as a background entry point: native can run it in a fresh isolate even while no Flutter UI is running (a WorkManager job, a push handler, a BGTask), hand it a string argument, and receive the string result. The generator emits the @pragma('vm:entry-point') wrapper that keeps the function alive under AOT, so the function itself needs no pragma.

nitroFast → const NitroFast

Marks a synchronous method as a hot path: the binding is isLeaf: true and the generated body is a bare call — no callSync closure, no logging/slow-call/timeline diagnostics. Measured on Apple Silicon this takes a generated call from ~260 ns to ~13 ns, level with a hand-written dart:ffi binding. The error slot is read in debug builds only (inside an assert), so a native throw surfaces as a HybridException during development and costs nothing in profile/release.

nitroNativeAsync → const NitroNativeAsync

nitroOwned → const NitroOwned

Const shorthand for @NitroOwned.

nitroResult → const NitroResult

Const shorthand for @NitroResult.

nitroVariant → const NitroVariant

Const shorthand for @NitroVariant.

zeroCopy → const ZeroCopy