Piper State

State management that gets out of your way.

Lifecycle-aware ViewModels, explicit dependencies, automatic cleanup. Patterns that have worked for years, now in Flutter.

Features

• StateHolder — Reactive state containers with automatic widget rebuilds
• AsyncState — Built-in loading/error/data states for async operations
• Stream bindings — Bind streams to state with automatic subscription management
• ViewModel — Lifecycle-aware base class with automatic resource cleanup
• Plain Dart — Core library has no Flutter dependency, test without widgets

Getting started

dependencies:
  piper_state: ^0.0.2
  flutter_piper: ^0.0.2  # For Flutter widgets

Usage

Basic state

class CounterViewModel extends ViewModel {
  late final count = state(0);

  void increment() => count.update((c) => c + 1);
}

Stream binding

State updates automatically, subscription auto-cancels on dispose:

class AuthViewModel extends ViewModel {
  AuthViewModel(AuthRepository auth);

  late final user = bind(_auth.userStream, initial: null);

  bool get isLoggedIn => user.value != null;
}

Async operations

Loading/error/data handled automatically:

late final profile = asyncState<Profile>();

void loadProfile() => load(profile, () => _repo.fetchProfile());

Why Piper?

• Explicit dependencies — Constructor injection, not magic
• Automatic lifecycle — No if (mounted) checks
• Plain Dart — Test without Flutter
• Incremental — Adopt one feature at a time

Additional information

• GitHub Repository
• flutter_piper — Flutter widgets for Piper State

License

MIT