Installing Ack

Ack is a pure-Dart package with no required build step. Add the core library — and, optionally, the code generator for immutable models.

Add to your project

Add Ack to your project using the Dart CLI:

# For Dart projects
dart pub add ack
 
# For Flutter projects
flutter pub add ack

Or add to your pubspec.yaml (check pub.dev  for the latest version):

dependencies:
  ack: ^1.2.0 # Replace with latest version

Optional code generator

To generate models from Ack schemas or Ack schemas from hand-written models, add the annotation and generator packages alongside ack:

dart pub add ack ack_annotations
dart pub add --dev ack_generator build_runner

Or add them to your pubspec.yaml:

dependencies:
  ack: ^1.2.0 # Replace with latest version
  ack_annotations: ^1.2.0 # Replace with latest version
 
dev_dependencies:
  ack_generator: ^1.2.0 # Replace with latest version
  build_runner: ^2.4.0

The generator works in both directions. @AckInfer() marks a top-level schema and generates an immutable model. @AckModel() marks a hand-written class and generates a public <ClassName>Schema facade, a private Ack codec, and JSON helpers. There is no @AckSchema() annotation; AckSchema is the runtime schema type.

import 'package:ack/ack.dart';
import 'package:ack_annotations/ack_annotations.dart';
 
part 'user.ack.dart';
part 'user.ack.g.dart';
 
@AckInfer()
final userSchema = Ack.object({
  'name': Ack.string(),
  'email': Ack.string().email(),
});
 
@AckModel()
final class Account with _$AccountAck {
  const Account({required this.name});
  final String name;
 
  static final fromJson = AccountSchema.fromJson;
}

Run the generator:

dart run build_runner build

See Model Code Generation for working tutorials, supported shapes, and guidance on choosing a direction.

Next step

Import package:ack/ack.dart and you’re ready — the Quickstart Tutorial takes you from your first schema to handling every validation outcome.

Requirements

• Dart SDK: >=3.9.0 <4.0.0 for core ack
• Dart SDK: >=3.9.0 <4.0.0 when using ack_annotations / ack_generator